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Zhang G, Wang M, Bobadova-Parvanova P, Fronczek FR, Smith KM, Vicente MGH. Investigations on the Synthesis, Reactivity, and Properties of Perfluoro-α-Benzo-Fused BOPHY Fluorophores. Chemistry 2022; 28:e202200421. [PMID: 35445459 DOI: 10.1002/chem.202200421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Indexed: 11/06/2022]
Abstract
The synthesis and reactivity of 3,8-dibromo-dodecafluoro-benzo-fused BOPHY 2 are reported, via SN Ar with O-, N- S- and C-nucleophiles, and in Pd(0)-catalyzed cross-coupling reactions (Suzuki and Stille). The resulting perfluoro-BOPHY derivatives were investigated for their reactivity in the presence of various nucleophiles. BOPHY 3 displays reversible color change and fluorescence quenching in the presence of bases (Et3 N, DBU), whereas BOPHY 7 reacts preferentially at the α-pyrrolic positions, and BOPHY 8 undergoes regioselective fluorine substitution in the presence of thiols. The structural and electronic features of the fluorinated BOPHYs were studied by TD-DFT computations. In addition, their spectroscopic and cellular properties were investigated; BOPHY 10 shows the most red-shifted absorption/emission (λmax 659/699 nm) and 7 the highest fluorescence (Φf =0.95), while all compounds studied showed low cytotoxicity toward human HEp2 cells and were efficiently internalized.
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Affiliation(s)
- Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Petia Bobadova-Parvanova
- Department of Chemistry and Fermentation Sciences, Appalachian State University, Boone, NC 28608, USA
| | - Frank R Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
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2
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Wang M, Zhang G, Bobadova-Parvanova P, Smith KM, Vicente MGH. Syntheses and Investigations of Conformationally Restricted, Linker-Free α-Amino Acid-BODIPYs via Boron Functionalization. J Org Chem 2021; 86:18030-18041. [PMID: 34807610 PMCID: PMC8689652 DOI: 10.1021/acs.joc.1c02328] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of α-amino acid-BODIPY derivatives were synthesized using commercially available N-Boc-l-amino acids, via boron functionalization under mild conditions. The mono-linear, mono-spiro, and di-amino acid-BODIPY derivatives were obtained using an excess of basic (histidine, lysine, and arginine), acidic (aspartic acid), polar (tyrosine, serine), and nonpolar (methionine) amino acid residues, in yields that ranged from 37 to 66%. The conformationally restricted mono-spiro- and di-amino acid-BODIPYs display strong absorptions in the visible spectral region with high molar extinction coefficients and significantly enhanced fluorescence quantum yields compared with the parent BF2-BODIPY. Cellular uptake and cytotoxicity studies using the human HEp2 cell line show that both the presence of an N,O-bidentate spiro-ring and basic amino acids (His and Arg) increase cytotoxicity and enhance cellular uptake. Among the series of BODIPYs tested, the spiro-Arg- and spiro-His-BODIPYs were found to be the most cytotoxic (IC50 ∼ 22 μM), while the spiro-His-BODIPY was the most efficiently internalized, localizing preferentially in the cell lysosomes, ER, and mitochondria.
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Affiliation(s)
- Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Petia Bobadova-Parvanova
- Department of Chemistry and Fermentation Sciences, Appalachian State University, Boone, North Carolina 28607, United States
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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3
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Zhang G, Wang M, Collins BR, Vicente MGH, Smith KM. Synthesis and cellular properties of a 131substituted chlorin e6-nevirapine conjugate. J PORPHYR PHTHALOCYA 2021. [DOI: 10.1142/s1088424621500632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The synthesis of a chlorin e6-nevirapine conjugate is reported, in which the nevirapine moiety is attached to the 131-position of chlorin e6 via a diethylene glycol linker. This conjugate was found to be nontoxic in the dark (IC[Formula: see text] > 200 [Formula: see text]M), but highly phototoxic (IC[Formula: see text] = 0.21 [Formula: see text]M at 1.5 J/cm[Formula: see text] toward human HEp2 cells. The chlorin e6-nevirapine conjugate accumulated within cells in multiple organelles, including the Golgi, lysosomes and mitochondria. On the other hand, nevirapine was found to be nontoxic to HEp2 cells.
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Affiliation(s)
- Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Brittany R. Collins
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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4
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Almeida J, Zhang G, Wang M, Queirós C, Cerqueira AFR, Tomé AC, Barone G, Vicente MGH, Hey-Hawkins E, Silva AMG, Rangel M. Synthesis, characterization, and cellular investigations of porphyrin- and chlorin-indomethacin conjugates for photodynamic therapy of cancer. Org Biomol Chem 2021; 19:6501-6512. [PMID: 34254099 DOI: 10.1039/d1ob01015h] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Indomethacin is a potent non-steroidal anti-inflammatory drug (NSAID) with a strong selective inhibitor activity towards cyclooxygenase-2 (COX-2), an enzyme that is highly overexpressed in various tumour cells, being involved in tumourigenesis. Concomitantly, porphyrins have gained much attention as promising photosensitizers (PSs) for the non-invasive photodynamic therapy (PDT) of cancer. Herein, we report the design, and determine the singlet oxygen generation capacity and in vitro cellular toxicity of porphyrin- and chlorin-indomethacin conjugates (P2-Ind and C2-Ind). Both the conjugates were obtained in high yields and were characterized by 1H, 19F and 13C NMR as well as by high resolution mass spectrometry. The singlet oxygen generation properties were assessed by the 1,3-diphenylisobenzofuran singlet oxygen trap method, which showed that C2 and C2-Ind are the best singlet oxygen photosensitizers. In addition, it was found that the presence of indomethacin did not influence the singlet oxygen generation of porphyrin or chlorin. Cytotoxicity studies of the conjugate in human HEp2 cells revealed that the porphyrin- and chlorin-indomethacin conjugates have similar dark cytotoxicities, while chlorin C2 was shown to be the most phototoxic. Despite having lower cellular uptake than C2-Ind after 24 hours, chlorin C2 had a broad localization in HEp2 cells while the chlorin-indomethacin conjugate C2-Ind could be detected in the form of small aggregates. DFT calculations were performed to shed light on the reaction energy involved in the formation of the indomethacin conjugates and to compare the relative stability of selected isomers in solution. Moreover, the calculated energy of their first excited triplet state structures confirmed their use as suitable photosensitizers to generate singlet oxygen for PDT.
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Affiliation(s)
- José Almeida
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal.
| | - Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Carla Queirós
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal.
| | - Ana F R Cerqueira
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Augusto C Tomé
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Giampaolo Barone
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche, Università di Palermo, Viale delle Scienze, Edificio 17, 90128 Palermo, Italy
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Ana M G Silva
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal.
| | - Maria Rangel
- LAQV-REQUIMTE, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4099-003 Porto, Portugal
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Zhang G, Wang M, Ndung’U C, Bobadova-Parvanova P, Fronczek FR, Smith KM, Vicente MGH. Synthesis and investigation of BODIPYs with restricted meso-8-aryl rotation. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s1088424619501967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Three BODIPYs bearing 1,3,5,7-tetramethyl substituents and a meso-8-aryl group were synthesized and investigated, both experimentally and computationally. The presence of the 1,7-methyl groups and of ortho-substituents on the meso-8-aryl ring prevent free rotation of the meso-8-aryl group, resulting in high fluorescence quantum yields. Substitution at the 2,6-positions of these BODIPYs with chlorine atoms causes pronounced red-shifted absorptions and emissions, and in the case of 2,6-dichloro-1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY 2c increases its fluorescence quantum yields to 0.93 in dichloromethane and 0.98 in toluene. The X-ray structure of 1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY shows increased deviation from planarity and smaller dihedral angle of the meso-8-aryl group compared with the meso-8-phenyl- and meso-8-mesityl-BODIPY analogs. The presence of 2,6-chlorine atoms was found to not significantly affect the rotational barriers of the meso-8-aryl-groups.
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Affiliation(s)
- Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Caroline Ndung’U
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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6
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Wang M, Zhang G, Kaufman NEM, Bobadova-Parvanova P, Fronczek FR, Smith KM, Vicente MGH. Linker-Free Near-IR Aza-BODIPY-Glutamine Conjugates Through Boron Functionalization. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901772] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Maodie Wang
- Department of Chemistry; Louisiana State University; LA 70803 Baton Rouge USA
| | - Guanyu Zhang
- Department of Chemistry; Louisiana State University; LA 70803 Baton Rouge USA
| | | | | | - Frank R. Fronczek
- Department of Chemistry; Louisiana State University; LA 70803 Baton Rouge USA
| | - Kevin M. Smith
- Department of Chemistry; Louisiana State University; LA 70803 Baton Rouge USA
| | - M. Graça H. Vicente
- Department of Chemistry; Louisiana State University; LA 70803 Baton Rouge USA
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7
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Moss A, Zhou Z, Jiang L, Vicente MGH, Wang H. Synthesis of highly water soluble tetrabenzoporphyrins and their application toward photodynamic therapy. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s1088424619501785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Novel tetraaryl-(pyridinium-4-yl)-tetrabenzoporphyrins have been successfully synthesized via a Heck-based sequence reaction. These tetrabenzoporphyrins were substituted with eight pyridyl groups at the fused benzene rings. Methylation of the pyridyl groups with methyl iodide afforded highly water soluble tetrabenzoporphyrins carrying eight ionic groups. The extended [Formula: see text]-conjugation broadened and red-shifted the absorption band of these porphyrins to 650–750 nm. These cationic tetrabenzoporphyrins showed non-toxicity in the dark up to 100 uM. High phototoxicity with IC[Formula: see text] values lower than 18 [Formula: see text]M were obtained for these tetrabenzoporphyrins.
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Affiliation(s)
- Austen Moss
- Department of Chemistry, University of North Texas, Denton, TX 76201, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Lin Jiang
- Division of Natural Sciences, New College of Florida, Sarasota, FL 34243, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Hong Wang
- Department of Chemistry, University of North Texas, Denton, TX 76201, USA
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8
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Fujishiro R, Sonoyama H, Ide Y, Fujimura T, Sasai R, Kaufman NEM, Zhou Z, Vicente MGH, Ikeue T. Singlet oxygen generation of subphthalocyanine-fused dimer and trimer. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s1088424619500895] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Subphthalocyanine (SubPc) macrocycles are known as an interesting class of nonplanar aromatic dyes. Despite documented high fluorescence and singlet oxygen quantum yields, the properties of SubPcs in photodynamic therapy (PDT) are underestimated, because their absorption bands do not reach a significant wavelength range. With this in mind, we combined a SubPc ring and a SubPc ring by introducing a common benzene ring and obtained a SubPc dimer (2) and trimer (3) with the Q-band at the near-IR region, owing to the expansion of the [Formula: see text] electron conjugated system. In this study, we reported1O2generation abilities of 2 and 3based on the applied absolute singlet oxygen quantum yields ([Formula: see text]absolute). Subsequent research revealed that 2 and 3 showed the potential to generate1O2to not only in toluene but also in DMSO. Although the photocytotoxicity of 2 and 3 were investigated upon photo-irradiation with a low light dose of approximately 1.5 J/cm2, 2 and 3 showed almost negligible toxic properties toward HEp2 cells.
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Affiliation(s)
- Rei Fujishiro
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Hayato Sonoyama
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Yuki Ide
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Takuya Fujimura
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Ryo Sasai
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Nichole E. M. Kaufman
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, USA
| | - Takahisa Ikeue
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
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9
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Wang M, Zhang G, Bobadova-Parvanova P, Merriweather AN, Odom L, Barbosa D, Fronczek FR, Smith KM, Vicente MGH. Synthesis and Investigation of Linker-Free BODIPY–Gly Conjugates Substituted at the Boron Atom. Inorg Chem 2019; 58:11614-11621. [DOI: 10.1021/acs.inorgchem.9b01474] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | | | - Ashley N. Merriweather
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Lilian Odom
- Department of Chemistry, Rockhurst University, Kansas City, Missouri 64110, United States
| | - David Barbosa
- Department of Chemistry, Rockhurst University, Kansas City, Missouri 64110, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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10
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Kaufman NEM, Meng Q, Griffin KE, Singh SS, Dahal A, Zhou Z, Fronczek FR, Mathis JM, Jois SD, Vicente MGH. Synthesis, Characterization, and Evaluation of Near-IR Boron Dipyrromethene Bioconjugates for Labeling of Adenocarcinomas by Selectively Targeting the Epidermal Growth Factor Receptor. J Med Chem 2019; 62:3323-3335. [PMID: 30835998 DOI: 10.1021/acs.jmedchem.8b01746] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of five boron dipyrromethene (BODIPY) bioconjugates containing an epidermal growth factor receptor (EGFR)-targeted pegylated LARLLT peptide and/or a glucose or biotin ethylene diamine group were synthesized, and the binding capability of the new conjugates to the extracellular domain of EGFR was investigated using molecular modeling, surface plasmon resonance, fluorescence microscopy, competitive binding assays, and animal studies. The BODIPY conjugates with a LARLLT peptide were found to bind specifically to EGFR, whereas those lacking the peptide bound weakly and nonspecifically. All BODIPY conjugates showed low cytotoxicity (IC50 > 94 μM) in HT-29 cells, both in the dark and upon light activation (1.5 J/cm2). Studies of nude mice bearing subcutaneous human HT-29 xenografts revealed that only BODIPY conjugates bearing the LARLLT peptide showed tumor localization 24 h after intravenous administration. The results of our studies demonstrate that BODIPY bioconjugates bearing the EGFR-targeting peptide 3PEG-LARLLT show promise as near-IR fluorescent imaging agents for colon cancers overexpressing EGFR.
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Affiliation(s)
- Nichole E M Kaufman
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Qianli Meng
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Kaitlin E Griffin
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Sitanshu S Singh
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy , University of Louisiana at Monroe , Monroe , Louisiana 71201 , United States
| | - Achyut Dahal
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy , University of Louisiana at Monroe , Monroe , Louisiana 71201 , United States
| | - Zehua Zhou
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Frank R Fronczek
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - J Michael Mathis
- Department of Comparative Biomedical Sciences , Louisiana State University School of Veterinary Medicine , Baton Rouge , Louisiana 70803 , United States
| | - Seetharama D Jois
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy , University of Louisiana at Monroe , Monroe , Louisiana 71201 , United States
| | - M Graça H Vicente
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
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11
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Taylor AM, Okoth EA, Arachchige NMK, Vicente MGH, Garno JC. Nanostructures of functionalized zinc phthalocyanines prepared with colloidal lithography: Evaluation of surface orientation and dimensions using scanning probe microscopy. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2018.12.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Abstract
An isothiocyanato-functionalized phthalocyanine (Pc) was synthesized in good yield from the corresponding amine-substituted Pc. This Pc reacted with ethanolamine, biotin hydrazine, and biotin diethylamine under mild conditions (room temperature in DMF or DMSO in the presence of TEA) to produce the corresponding thiourea products in 60-75% yields. All Pcs showed intense Q absorptions in DMF around 677 nm, emissions centered at 683 nm, and fluorescence quantum yields in the range 0.18-0.27. The Pcs were phototoxic to human carcinoma HEp2 cells (IC50 ~ 7 at 1.5 J/cm2) and localized in multiple organelles, including the lysosomes, Golgi and ER. One biotin-Pc conjugate was injected via tail vein into nude mice bearing HT-29 tumors and demonstrated selective localization in the tumor tissue.
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Affiliation(s)
- Elizabeth A. Okoth
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Benson Ongarora
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Alyssa Stutes
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - J. Michael Mathis
- Department of Comparative Biomedical Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge Louisiana 70803, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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13
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Fujishiro R, Sonoyama H, Ide Y, Fujimura T, Sasai R, Nagai A, Mori S, Kaufman NEM, Zhou Z, Vicente MGH, Ikeue T. Synthesis, photodynamic activities, and cytotoxicity of new water-soluble cationic gallium(III) and zinc(II) phthalocyanines. J Inorg Biochem 2018; 192:7-16. [PMID: 30551005 DOI: 10.1016/j.jinorgbio.2018.11.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/22/2022]
Abstract
The cationic Ga(III) and Zn(II) phthalocyanines carrying N-methyl-pyridinium groups at eight peripheral β-positionshave been synthesized. These complexes are highly soluble in dimethyl sulfoxide (DMSO) and moderately soluble in water and phosphate buffered saline (PBS); both Ga(III)Cl and Zn(II) complexes have shown no aggregation in water up to 1.2 × 10-4 and 1.5 × 10-5 M, respectively. A higher water-solubility of Ga(III)Cl complex as compared to Zn(II) complex is ascribed to the presence of an axially coordinated chloride. The spectroscopic properties, photogeneration of singlet oxygen (1O2), and cytotoxicity of these complexes have been investigated. The absolute quantum yields (ΦΔabsolute) for the photogeneration of singlet oxygen using Ga(III)Cl and Zn(II) complexes have been determined to be 4.4 and 5.3%, respectively, in DMSO solution. The cytotoxicity and intracellular sites of localization of Ga(III)Cl and Zn(II) complexes have been evaluated in human HEp2 cells. Both complexes, localized intracellularly in multiple organelles, have shown no cytotoxicity in the dark. Upon exposure to a low light dose (1.5 J/cm2), however, Zn(II) complex has exhibited a high photocytotoxicity. The result suggests that Zn(II) complex can be considered as a potential photosensitizer for Photodynamic therapy (PDT).
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Affiliation(s)
- Rei Fujishiro
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Hayato Sonoyama
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Yuki Ide
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Takuya Fujimura
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Ryo Sasai
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan.
| | - Atsushi Nagai
- Department of Laboratory Medicine, Shimane University School of Medicine, Izumo, Japan
| | - Shigeki Mori
- Advanced Research Support Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Japan
| | - Nichole E M Kaufman
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA
| | - Takahisa Ikeue
- Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan.
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14
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Zhang G, Wang M, Fronczek FR, Smith KM, Vicente MGH. Lewis-Acid-Catalyzed BODIPY Boron Functionalization Using Trimethylsilyl Nucleophiles. Inorg Chem 2018; 57:14493-14496. [DOI: 10.1021/acs.inorgchem.8b02775] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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15
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LaMaster DJ, Kaufman NEM, Bruner AS, Vicente MGH. Structure Based Modulation of Electron Dynamics in meso-(4-Pyridyl)-BODIPYs: A Computational and Synthetic Approach. J Phys Chem A 2018; 122:6372-6380. [PMID: 30016866 PMCID: PMC6693353 DOI: 10.1021/acs.jpca.8b05153] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effects of structural modification on the electronic structure and electron dynamics of cationic meso-(4-pyridyl)-BODIPYs were investigated. A library of 2,6-difunctionalized meso-(4-pyridyl)-BODIPYs bearing various electron-withdrawing substituents was designed, and DFT calculations were used to model the redox properties, while TDDFT was used to determine the effects of functionalization on the excited states. Structural modification was able to restructure the low-lying molecular orbitals to effectively inhibit d-PeT. A new meso-(4-pyridyl)-BODIPY bearing 2,6-dichloro groups was synthesized and shown to exhibit enhanced charge recombination fluorescence. The fluorescence enhancement was determined to be the result of functionalization modulating the kinetics of the excited state dynamics.
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Affiliation(s)
- Daniel J. LaMaster
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Nichole E. M. Kaufman
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Adam S. Bruner
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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16
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Zhang G, Zhao N, Bobadova-Parvanova P, Wang M, Fronczek FR, Smith KM, Vicente MGH. Syntheses, Spectroscopic Properties, and Computational Study of (E,Z)-Ethenyl and Ethynyl-Linked BODIPYs. J Phys Chem A 2018; 122:6256-6265. [DOI: 10.1021/acs.jpca.8b05149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Guanyu Zhang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | | | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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17
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Savoldelli A, Meng Q, Paolesse R, Fronczek FR, Smith KM, Vicente MGH. Tetrafluorobenzo-Fused BODIPY: A Platform for Regioselective Synthesis of BODIPY Dye Derivatives. J Org Chem 2018; 83:6498-6507. [PMID: 29774744 DOI: 10.1021/acs.joc.8b00789] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A novel route for the synthesis of unsymmetrical benzo-fused BODIPYs is reported using 4,5,6,7-tetrafluoroisoindole as a precursor. The reactivity of the 3,5-dibromo tetrafluorobenzo-fused BODIPY was investigated under nucleophilic substitution and Pd(0)-catalyzed cross-coupling reaction conditions. In addition to the 3,5-bromines, one α-fluoro group on the benzo-fused ring can also be functionalized, and an unusual homocoupling with formation of a bisBODIPY was observed. This new class of fluorinated BODIPYs could find various applications in medicine and materials.
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Affiliation(s)
- Andrea Savoldelli
- Dipartimento di Scienze e Tecnologie Chimiche , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 Rome , Italy
| | - Qianli Meng
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Roberto Paolesse
- Dipartimento di Scienze e Tecnologie Chimiche , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 Rome , Italy
| | - Frank R Fronczek
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Kevin M Smith
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - M Graça H Vicente
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
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18
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Williams TM, Sable R, Singh S, Vicente MGH, Jois S. Peptide ligands for targeting the extracellular domain of EGFR: Comparison between linear and cyclic peptides. Chem Biol Drug Des 2018; 91:605-619. [PMID: 29052959 PMCID: PMC5775921 DOI: 10.1111/cbdd.13125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/27/2017] [Accepted: 10/04/2017] [Indexed: 01/08/2023]
Abstract
Colorectal cancer (CRC) is the third most common solid internal malignancy among cancers. Early detection of cancer is key to increasing the survival rate of colorectal cancer patients. Overexpression of the EGFR protein is associated with CRC. We have designed a series of peptides that are highly specific for the extracellular domain of EGFR, based on our earlier studies on linear peptides. The previously reported linear peptide LARLLT, known to bind to EGFR, was modified with the goals of increasing its stability and its specificity toward EGFR. Peptide modifications, including D-amino acid substitution, cyclization, and chain reversal, were investigated. In addition, to facilitate labeling of the peptide with a fluorescent dye, an additional lysine residue was introduced onto the linear (KLARLLT) and cyclic peptides cyclo(KLARLLT) (Cyclo.L1). The lysine residue was also converted into an azide group in both a linear and reversed cyclic peptide sequences cyclo(K(N3)larllt) (Cyclo.L1.1) to allow for subsequent "click" conjugation. The cyclic peptides showed enhanced binding to EGFR by SPR. NMR and molecular modeling studies suggest that the peptides acquire a β-turn structure in solution. In vitro stability studies in human serum show that the cyclic peptide is more stable than the linear peptide.
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Affiliation(s)
- Tyrslai M. Williams
- Department of Chemistry, Louisiana State University, Baton Rouge LA 70803, USA
| | - Rushikesh Sable
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe LA 71201, USA
| | - Sitanshu Singh
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe LA 71201, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge LA 70803, USA
| | - Seetharama Jois
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe LA 71201, USA
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19
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Abstract
BODIPYs bearing up to three glucose units were synthesized and their cytotoxicity and uptake investigated in human HEp2 cells.
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Affiliation(s)
- Alex L. Nguyen
- Department of Chemistry
- Louisiana State University
- Baton Rouge
- USA
| | | | - Zehua Zhou
- Department of Chemistry
- Louisiana State University
- Baton Rouge
- USA
| | | | - Kevin M. Smith
- Department of Chemistry
- Louisiana State University
- Baton Rouge
- USA
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20
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Chen H, Humble SW, Waruna Jinadasa RG, Zhou Z, Nguyen AL, Vicente MGH, Smith KM. Syntheses and PDT activity of new mono- and di-conjugated derivatives of chlorin e 6. J PORPHYR PHTHALOCYA 2017; 21:354-363. [PMID: 29056848 DOI: 10.1142/s1088424617500262] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Syntheses of three new chlorin e6 conjugates for PDT of tumors are reported. One of the new compounds 17 is conjugated with lysine at the 131-position, but the others are mono-conjugated 14 or diconjugated 15 with the non-amino acid species ethanolamine. Cellular experiments with the three new compounds and previously synthesized non-amino acid 152-conjugates (7-10), 131-monoconjugates 14, 16, and a 131,152-diconjugate 12 are reported. In vitro cytotoxicity experiments show that the 131-conjugates are more toxic than the 152-conjugates, and the most toxic derivative (dark- and photo-toxicity) is the 131-ethylenediamine conjugate 11. The most useful PDT photosentitizers appear to be the ethanolamine derivatives, conjugated at the 152- and the 131,152-positions; these show high phototoxicity but relatively low dark toxicity compared with 11, and also the highest dark/photo cytotoxicity ratios.
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Affiliation(s)
- Hui Chen
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Stewart W Humble
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - R G Waruna Jinadasa
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Alex L Nguyen
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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21
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Zhao N, Xuan S, Zhou Z, Fronczek FR, Smith KM, Vicente MGH. Synthesis and Spectroscopic and Cellular Properties of Near-IR [a]Phenanthrene-Fused 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacenes. J Org Chem 2017; 82:9744-9750. [DOI: 10.1021/acs.joc.7b01940] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sunting Xuan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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22
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Zhao N, Williams TM, Zhou Z, Fronczek FR, Sibrian-Vazquez M, Jois SD, Vicente MGH. Synthesis of BODIPY-Peptide Conjugates for Fluorescence Labeling of EGFR Overexpressing Cells. Bioconjug Chem 2017; 28:1566-1579. [PMID: 28414435 DOI: 10.1021/acs.bioconjchem.7b00211] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Regioselective functionalization of 2,3,5,6,8-pentachloro-BODIPY 1 produced unsymmetric BODIPY 5, bearing an isothiocyanate group suitable for conjugation, in only four steps. The X-ray structure of 5 reveals a nearly planar BODIPY core with aryl dihedral angles in the range 47.4-62.9°. Conjugation of 5 to two EGFR-targeting pegylated peptides, 3PEG-LARLLT (6) and 3PEG-GYHWYGYTPQNVI (7), under mild conditions (30 min at room temperature), afforded BODIPY conjugates 8 and 9 in 50-80% isolated yields. These conjugates showed red-shifted absorption and emission spectra compared with 5, in the near-IR region, and were evaluated as potential fluorescence imaging agents for EGFR overexpressing cells. SPR and docking investigations suggested that conjugate 8 bearing the LARLLT sequence binds to EGFR more effectively than 9 bearing the GYHWYGYTPQNVI peptide, in part due to the lower solubility of 9, and its tendency for aggregation at concentrations above 10 μM. Studies in human carcinoma HEp2 cells overexpressing EGFR demonstrated low dark and photo cytotoxicities for BODIPY 5 and the two peptide conjugates, and remarkably high cellular uptake for both conjugates 8 and 9, up to 90-fold compared with BODIPY 5 after 1 h. Fluorescence imaging studies in HEp2 cells revealed subcellular localization of the BODIPY-peptide conjugates mainly in the Golgi apparatus and the cell lysosomes. The low cytotoxicity of the new conjugates and their remarkably high uptake into EGFR overexpressing cells renders them promising imaging agents for cancers overexpressing EGFR.
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Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Tyrslai M Williams
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Frank R Fronczek
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Martha Sibrian-Vazquez
- Department of Chemistry, Portland State University , Portland, Oregon 97201, United States
| | - Seetharama D Jois
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe , Monroe, Louisiana 71201, United States
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
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23
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Zhao N, Xuan S, Fronczek FR, Smith KM, Vicente MGH. Enhanced Hypsochromic Shifts, Quantum Yield, and π-π Interactions in a meso,β-Heteroaryl-Fused BODIPY. J Org Chem 2017; 82:3880-3885. [PMID: 28231707 PMCID: PMC5507578 DOI: 10.1021/acs.joc.6b02981] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We report the synthesis and investigation of an unprecedented 8-heteroaryl-fused BODIPY 4. This compound exhibits enhanced π-π stacking in the solid state, unusually large blue-shifts in the absorbance and emission spectra, and higher fluorescence quantum yield than its unfused precursor; DFT calculations suggest a small energy gap for 4 and strong electronic communication between the 8-OPh and the BODIPY core.
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Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sunting Xuan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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24
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Xuan S, Zhao N, Ke X, Zhou Z, Fronczek FR, Kadish KM, Smith KM, Vicente MGH. Synthesis and Spectroscopic Investigation of a Series of Push-Pull Boron Dipyrromethenes (BODIPYs). J Org Chem 2017; 82:2545-2557. [PMID: 28150499 PMCID: PMC5510570 DOI: 10.1021/acs.joc.6b02941] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A series of push-pull BODIPYs bearing multiple electron-donating and electron-acceptor groups were synthesized regioselectively from 2,3,5,6,8-pentachloro-BODIPY, and characterized by NMR spectroscopy, HRMS, and X-ray crystallography. The influence of the push-pull substituents on the spectroscopic and electrochemical properties of BODIPYs was investigated. Bathochromic shifts were observed for both absorbance (up to 37 nm) and emission (up to 60 nm) in different solvents upon introduction of the push-pull moieties. DFT calculations, consistent with the spectroscopic and cyclic voltammetry studies, show decreased HOMO-LUMO energy gaps upon the installation of the push-pull moieties. BODIPY 7 bearing thienyl groups on the 2 and 6 positions showed the largest λmax for both absorption (635-653 nm) and emission (706-707 nm), but also the lowest fluorescence quantum yields. All BODIPYs were nontoxic in the dark (IC50 > 200 μM) and showed low phototoxicity (IC50 > 100 μM, 1.5 J/cm2) toward human HEp2 cells. Despite the relatively low fluorescence quantum yields, the push-pull BODIPYS were effective for cell imaging, readily accumulating within cells and localizing mainly in the ER and Golgi. Our structure-property studies can guide future design of functionalized BODIPYs for various applications, including bioimaging and in dye-sensitized solar cells.
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Affiliation(s)
- Sunting Xuan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Xiangyi Ke
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Karl M. Kadish
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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25
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Abstract
A series of boron-functionalized BODIPY dyes with cyano groups were prepared from their corresponding BF2derivatives using SnCl4/TMSCN at room temperature for 10 min. Replacement of the fluorines by cyano groups reduces the B–N bond lengths, decreases the charge on boron, and causes characteristic [Formula: see text]B NMR chemical shifts. The 4,4[Formula: see text]-dicyano-BODIPYs show significantly enhanced stability to acidic conditions (excess TFA) and, with one exception, enhanced fluorescence quantum yields. Furthermore, the B(CN)2-BODIPYs were non-cytotoxic to HEp2 cells, both in the dark and upon exposure to light (1.5 J/cm[Formula: see text], and rapidly accumulated within cells, localizing mainly in the lysosomes, ER and Golgi.
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Affiliation(s)
- Alex L. Nguyen
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Maodie Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Quynh Do
- Department of Chemistry, Rockhurst University, Kansas City, MO 64110, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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26
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Abstract
Asymmetric BODIPY dyads are synthesized from a,c-biladiene salts in good yields. The reactivity of a 5,5′-dibromo-BODIPY dyad was investigated.
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Affiliation(s)
- Andrea Savoldelli
- Dipartimento di Scienze e Tecnologie Chimiche
- Università di Roma “Tor Vergata”
- 00133 Rome
- Italy
| | - Roberto Paolesse
- Dipartimento di Scienze e Tecnologie Chimiche
- Università di Roma “Tor Vergata”
- 00133 Rome
- Italy
| | - Frank R. Fronczek
- Department of Chemistry
- Louisiana State University
- 70803 Baton Rouge
- USA
| | - Kevin M. Smith
- Department of Chemistry
- Louisiana State University
- 70803 Baton Rouge
- USA
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27
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Zhao N, Fabre B, Bobadova-Parvanova P, Fronczek FR, Vicente MGH. Synthesis and electropolymerization of a series of 2,2′-(ortho-carboranyl)bisthiophenes. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2016.11.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Zhao N, Xuan S, Byrd B, Fronczek FR, Smith KM, Vicente MGH. Synthesis and regioselective functionalization of perhalogenated BODIPYs. Org Biomol Chem 2016; 14:6184-8. [PMID: 27251595 DOI: 10.1039/c6ob00935b] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three perhalogenated BODIPYs (1b-3b), bearing chloro and bromo groups at all carbon positions, were synthesized and characterized. The reactivity of BODIPY 3b was investigated under Stille cross-coupling reactions, and single crystal X-ray analysis was used to confirm the regioselectivity of the reactions. Further substitution at the boron atom produced nona-functionalized BODIPYs 7a,b, which show 676 and 739 nm emissions with 91 and 100 nm Stokes shifts, respectively.
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Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
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29
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Xuan S, Zhao N, Zhou Z, Fronczek FR, Vicente MGH. Synthesis and in Vitro Studies of a Series of Carborane-Containing Boron Dipyrromethenes (BODIPYs). J Med Chem 2016; 59:2109-17. [PMID: 26849474 DOI: 10.1021/acs.jmedchem.5b01783] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A series of seven BODIPYs functionalized with ortho-carborane groups at the 8(meso) or 3/5(α) position were synthesized and characterized by NMR, HRMS, HPLC, and in the cases of 2b and 5b, by X-ray analysis. The BODIPYs exhibited low dark toxicity and phototoxicity toward human glioma T98G cells, and their cellular uptake varied significantly, with 5b accumulating the most and 7 the least. All BODIPYs localized mainly within the cell ER. The BODIPYs showed higher permeabilities than lucifer yellow across human hCMEC/D3 brain endothelial cell monolayers as the BBB model. Among this series, 1b showed the highest BBB permeability (Pe = 16.4 × 10(-5) cm/s), probably as a result of its lower MW (366 Da) and favorable hydrophobicity (log P = 1.5). The combination of low cytotoxicity, amphiphilicity, high boron content, high cellular uptake, and moderate BBB permeability renders these compounds promising boron delivery agents for the BNCT of brain tumors.
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Affiliation(s)
- Sunting Xuan
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Ning Zhao
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Frank R Fronczek
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
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30
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Abstract
A series of β,β'-bicyclo-3,5-diaryl-BODIPYs were synthesized from the corresponding β,β'-bicyclo-3,5-diiodo-BODIPYs (1a,b) via Pd(0)-mediated Suzuki cross-coupling reactions in 82-92% yields. Subsequent aromatization with DDQ afforded the corresponding β,β'-dibenzo-aryl-BODIPYs, which showed red-shifted absorptions and emissions in the near-IR range. The dibenzo-appended BODIPYs showed characteristic 1H-, 13C-, 11B- and 19F-NMR shifts, and nearly planar conformations by X-ray crystallography.
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Affiliation(s)
- Qianli Meng
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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31
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Jinadasa RGW, Zhou Z, Vicente MGH, Smith KM. Syntheses and cellular investigations of di-aspartate and aspartate-lysine chlorin e(6) conjugates. Org Biomol Chem 2016; 14:1049-64. [PMID: 26633562 PMCID: PMC4701634 DOI: 10.1039/c5ob02241j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Chlorin e6 is a tricarboxylic acid degradation product of chlorophyll a. Four chlorin e6 bis(amino acid) conjugates were regioselectively synthesized bearing two aspartate conjugates in the 13(1),17(3)- and 15(2),17(3)-positions, or at the 13(1),15(2)via an ethylene diamine linker. One additional conjugate bearing two different amino acids, lysine at 13(1)via an ethylene diamine linker and an aspartate at 15(2)via a β-alanine linker was also synthesized. The cytotoxicity and uptake of four di(amino acid) chlorin e6 conjugates were investigated in human HEp2 cells, and compared with chlorin e6. The most cytotoxic and most taken up conjugates were the zwitterionic 13(1),15(2)-disubstituted conjugates 28 and 33; these also localized in multiple organelles. In contrast, the anionic 13(1),17(3)- and 15(2),17(3)-di-aspartyl chlorin e6 conjugates 12 and 13 showed low dark cytoxicity and lower phototoxicity compared with chlorin e6.
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Affiliation(s)
- R G Waruna Jinadasa
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
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32
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Hollingsworth JV, Bhupathiraju NVSDK, Sun J, Lochner E, Vicente MGH, Russo PS. Preparation of Metalloporphyrin-Bound Superparamagnetic Silica Particles via "Click" Reaction. ACS Appl Mater Interfaces 2016; 8:792-801. [PMID: 26691852 PMCID: PMC4893945 DOI: 10.1021/acsami.5b10034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A facile approach using click chemistry is demonstrated for immobilization of metalloporphyrins onto the surface of silica-coated iron oxide particles. Oleic-acid stabilized iron oxide nanocrystals were prepared by thermal decomposition of iron(III) acetylacetonate. Their crystallinity, morphology, and superparamagnetism were determined using X-ray diffraction, transmission electron microscopy, and a superconducting quantum interference device. Monodisperse core-shell particles were produced in the silica-coating of iron oxide via microemulsion synthesis. Surface modification of these particles was performed in two steps, which included the reaction of silica-coated iron oxide particles with 3-bromopropyltrichlorosilane, followed by azido-functionalization with sodium azide. Monoalkylated porphyrins were prepared using the Williamson ether synthesis of commercially available tetra(4-hydroxyphenyl) porphyrin with propargyl bromide in the presence of a base. (1)H NMR and matrix-assisted laser desorption ionization confirmed the identity of the compounds. The prepared monoalkyne porphyrins were zinc-metalated prior to their introduction to azide-functionalized, silica-coated iron oxide particles in the click reaction. X-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy were used to characterize the surface chemistry after each step in the reaction. In addition, particle size was determined using dynamic light scattering and microscopy. The presented methodology is versatile and can be extended to other photoreactive systems, such as phthalocyanines and boron-dipyrromethane, which may lead to new materials for optical, photonic, and biological applications.
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Affiliation(s)
- Javoris V. Hollingsworth
- Department of Chemistry and Macromolecular Studies Group, Louisiana State University, Baton Rouge, Louisiana 70803, United States
- Department of Chemistry & Physics, University of St. Thomas, Houston, Texas 77006, United States
| | - N. V. S. Dinesh K. Bhupathiraju
- Department of Chemistry and Macromolecular Studies Group, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Jirun Sun
- Dr. Anthony Volpe Research Center, American Dental Association Foundation, 100 Bureau Drive, Stop 8546, Gaithersburg, Maryland 20899, United States
| | - Eric Lochner
- Department of Physics, Florida State University, Tallahassee, Florida 32306, United States
| | - M. Graça H. Vicente
- Department of Chemistry and Macromolecular Studies Group, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Paul S. Russo
- Department of Chemistry and Macromolecular Studies Group, Louisiana State University, Baton Rouge, Louisiana 70803, United States
- School of Materials Science and Engineering, School of Chemistry and Biochemistry and Georgia Tech Polymer Network, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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33
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Hiramatsu R, Kawabata S, Tanaka H, Sakurai Y, Suzuki M, Ono K, Miyatake SI, Kuroiwa T, Hao E, Vicente MGH. Tetrakis(p-Carboranylthio-Tetrafluorophenyl)Chlorin (TPFC): Application for Photodynamic Therapy and Boron Neutron Capture Therapy. J Pharm Sci 2016; 104:962-970. [PMID: 28756849 DOI: 10.1002/jps.24317] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 11/24/2014] [Accepted: 12/02/2014] [Indexed: 11/06/2022]
Abstract
Carboranyl-containing chlorins have emerged as promising dual sensitizers for use in both photodynamic therapy (PDT) and boron neutron capture therapy (BNCT), by virtue of their known tumor affinity, low cytotoxicity in dark conditions, and their strong absorptions in the red region of the optical spectrum. Tetrakis(p-carboranylthio-tetrafluorophenyl)chlorin (TPFC) is a new synthetic carboranyl-containing chlorin of high boron content (24% by weight). To evaluate TPFC's applicability as sensitizer for both PDT and BNCT, we performed an in vitro and in vivo study using F98 rat glioma cells and F98 rat glioma-bearing brain tumor models. For the in vivo BNCT study, we used boronophenylalanine (BPA), which is currently used in clinical BNCT studies, via intravenous administration (i.v.) and/or used TPFC via convection-enhanced delivery (CED), a method for local drug infusion directly into the brain. In the in vitro PDT study, the cell surviving fraction following laser irradiation (9J/cm2) was 0.035 whereas in the in vitro BNCT study, the cell surviving fraction following neutron irradiation (thermal neutron=1.73×1012 n/cm2) was 0.04. In the in vivo BNCT study, the median survival time following concomitant administration of BPA (i.v.) and TPFC (CED) was 42days (95% confidence interval; 37-43days). © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.
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Affiliation(s)
- Ryo Hiramatsu
- Department of Neurosurgery, Osaka Medical College, Osaka, Japan 569-8686
| | - Shinji Kawabata
- Department of Neurosurgery, Osaka Medical College, Osaka, Japan 569-8686.
| | - Hiroki Tanaka
- Kyoto University Research Reactor Institue, Kumatori, Osaka, Japan 590-0494
| | - Yoshinori Sakurai
- Kyoto University Research Reactor Institue, Kumatori, Osaka, Japan 590-0494
| | - Minoru Suzuki
- Kyoto University Research Reactor Institue, Kumatori, Osaka, Japan 590-0494
| | - Koji Ono
- Kyoto University Research Reactor Institue, Kumatori, Osaka, Japan 590-0494
| | - Shin-Ichi Miyatake
- Department of Neurosurgery, Osaka Medical College, Osaka, Japan 569-8686
| | - Toshihiko Kuroiwa
- Department of Neurosurgery, Osaka Medical College, Osaka, Japan 569-8686
| | - Erhong Hao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
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34
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Fontenot KR, Ongarora BG, LeBlanc LE, Zhou Z, Jois SD, Vicente MGH. Targeting of the epidermal growth factor receptor with mesoporphyrin IX-peptide conjugates. J PORPHYR PHTHALOCYA 2016; 20:352-366. [PMID: 27738394 PMCID: PMC5058426 DOI: 10.1142/s1088424616500115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The synthesis and in vitro evaluation of four mesoporphyrin IX-peptide conjugates designed to target EGFR, over-expressed in colorectal and other cancers, are reported. Two peptides with known affinity for EGFR, LARLLT (1) and GYHWYGYTPQNVI (2), were conjugated to mesoporphyrin IX (MPIX, 3) via one or both the propionic side chains, directly (4, 5) or with a triethylene glycol spacer (7, 8). The conjugates were characterized using NMR, MS, CD, SPR, UV-vis and fluorescence spectroscopies. Energy minimization and molecular dynamics suggest different conformations for the conjugates. SPR studies show that conjugate 4, bearing two LARLLT with no PEG spacers, has the greatest affinity for binding to EGFR, followed by conjugate 7 with two PEG and two LARLLT sequences. Molecular modeling and docking studies suggest that both conjugates 4 and 7 can bind to monomer and dimer EGFR in open and closed conformations. The cytotoxicity and cellular targeting ability of the conjugates were investigated in human HEp2 cells over-expressing EGFR. All conjugates showed low dark- and photo-toxicities. The cellular uptake was highest for conjugates 4 and 8 and lowest for 7 bearing two LARLLT linked via PEG groups, likely due to decreased hydrophobicity. Among the conjugates investigated 4 is the most efficient EGFR-targeting agent, and therefore the most promising for the detection of cancers that over-express EGFR.
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Affiliation(s)
- Krystal R. Fontenot
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Benson G. Ongarora
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Logan E. LeBlanc
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Seetharama D. Jois
- University of Louisiana at Monroe, School of Pharmacy, Monroe, LA 71201, USA
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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35
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Abstract
A series of four BODIPYs containing one or two ortho- or para-carborane clusters were synthesized using palladium(0)-catalyzed Suzuki cross-coupling or nucleophilic substitution reactions, at the 2,6- or the 8-positions of halogenated boron dipyrromethenes (BODIPYs). The spectroscopic, structural (including one X-ray) and in vitro BBB permeability of the BODIPYs using hCMEC/D3 brain endothelial cells were investigated.
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Affiliation(s)
- Jaime H Gibbs
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Haijun Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Frank R Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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36
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37
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Zhao N, Xuan S, Fronczek FR, Smith KM, Vicente MGH. Stepwise Polychlorination of 8-Chloro-BODIPY and Regioselective Functionalization of 2,3,5,6,8-Pentachloro-BODIPY. J Org Chem 2015; 80:8377-83. [PMID: 26186141 DOI: 10.1021/acs.joc.5b01147] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An effective, stepwise methodology for polychlorination of BODIPY using trichloroisocyanuric acid (TCCA) in acetic acid was developed. In this way, selectively substituted di-, tri-, tetra-, and pentachloro-BODIPYs 2-5 were prepared. The pentachloro-BODIPY is shown to undergo regioselective Pd(0)-catalyzed Stille and Suzuki coupling reactions, first at the 8-position followed by the 3,5- and then the 2,6-positions; nucleophilic substitution reactions occur first at the 8- followed by the 3,5-positions, while the 2,6 are unreactive.
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Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sunting Xuan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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38
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Zhao N, Vicente MGH, Fronczek FR, Smith KM. Synthesis of 3,8-dichloro-6-ethyl-1,2,5,7-tetramethyl-BODIPY from an asymmetric dipyrroketone and reactivity studies at the 3,5,8-positions. Chemistry 2015; 21:6181-92. [PMID: 25761150 PMCID: PMC4382426 DOI: 10.1002/chem.201406550] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Indexed: 01/23/2023]
Abstract
The asymmetric BODIPY 1 a (BODIPY=4,4-difluoro-4-bora-3a,4a-diaza-s-indacene), containing two chloro substituents at the 3,8-positions and a reactive 5-methyl group, was synthesized from the asymmetric dipyrroketone 3, which was readily obtained from available pyrrole 2 a. The reactivity of 3,8-dichloro-6-ethyl-1,2,5,7-tetramethyl-BODIPY 1 a was investigated by using four types of reactions. This versatile BODIPY undergoes regioselective Pd(0) -catalyzed Stille coupling reactions and/or regioselective nucleophilic addition/elimination reactions, first at the 8-chloro and then at the 3-chloro group, using a variety of organostannanes and N-, O-, and S-centered nucleophiles. On the other hand, the more reactive 5-methyl group undergoes regioselective Knoevenagel condensation with an aryl aldehyde to produce a monostyryl-BODIPY, and oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) gives the corresponding 5-formyl-BODIPY. Investigation of the reactivity of asymmetric BODIPY 1 a led to the preparation of a variety of functionalized BODIPYs with λmax of absorption and emission in the ranges 487-587 and 521-617 nm, respectively. The longest absorbing/emitting compound was the monostyryl-BODIPY 16, and the largest Stokes shift (49 nm) and fluorescence quantum yield (0.94) were measured for 5-thienyl-8-phenoxy-BODIPY 15. The structural properties (including 16 X-ray structures) of the new series of BODIPYs were investigated.
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Affiliation(s)
- Ning Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803 (USA)
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803 (USA)
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803 (USA)
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803 (USA)
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39
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Nguyen AL, Bobadova-Parvanova P, Hopfinger M, Fronczek FR, Smith KM, Vicente MGH. Synthesis and Reactivity of 4,4-Dialkoxy-BODIPYs: An Experimental and Computational Study. Inorg Chem 2015; 54:3228-36. [DOI: 10.1021/ic502821m] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Alex L. Nguyen
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | | | - Melissa Hopfinger
- Department
of Chemistry, Rockhurst University, Kansas City, Missouri 64110, United States
| | - Frank R. Fronczek
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kevin M. Smith
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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40
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Gibbs JH, Zhou Z, Kessel D, Fronczek FR, Pakhomova S, Vicente MGH. Synthesis, spectroscopic, and in vitro investigations of 2,6-diiodo-BODIPYs with PDT and bioimaging applications. J Photochem Photobiol B 2015; 145:35-47. [PMID: 25771382 DOI: 10.1016/j.jphotobiol.2015.02.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 02/02/2015] [Accepted: 02/08/2015] [Indexed: 10/23/2022]
Abstract
A series of five mono-styryl and their corresponding symmetric di-styryl-2,6-diiodo-BODIPYs containing indolyl, pyrrolyl, thienyl or tri(ethylene glycol)phenyl groups were synthesized using Knoevenagel condensations. The yields for the condensation reactions were improved up to 40% using microwave irradiation (90°C for 1h at 400W) due to lower decomposition of BODIPYs upon prolonged heating. The spectroscopic, structural (including the X-ray of a di-styryl-2,6-diiodo-BODIPY) and in vitro properties of the BODIPYs were investigated. The extension of π-conjugation through the 3,5-dimethyls of the known phototoxic 2,6-diiodo-BODIPY 1 produced bathochromic shifts in the absorption and emission spectra, in the order of 63-125nm for the mono-styryl- and 128-220nm for the di-styryl-BODIPYs in DMSO. The largest red-shifts were observed for the indolyl-containing BODIPYs while the largest fluorescence quantum yields were observed for the tri(ethyleneglycol)phenylstyryl-BODIPYs. Among this series, only the mono-styryl-BODIPYs were phototoxic (IC50=2-15μM at 1.5J/cm(2)), and were observed to localize preferentially in the cell ER and mitochondria. On the other hand, the di-styryl-BODIPYs were found to have low or no phototoxicity (IC50>100μM at 1.5J/cm(2)). Among this series of compounds BODIPY 2a shows the most promise for application as photosensitizer in PDT.
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Affiliation(s)
- Jaime H Gibbs
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - David Kessel
- Department of Pharmacology, Wayne State University, School of Medicine, Detroit, MI 48201, USA
| | - Frank R Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Svetlana Pakhomova
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
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41
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Ongarora BG, Zhou Z, Okoth EA, Kolesnichenko I, Smith KM, Vicente MGH. Synthesis, spectroscopic, and cellular properties of α-pegylated cis-A 2B 2- and A 3B-types ZnPcs. J PORPHYR PHTHALOCYA 2014; 18:1021-1033. [PMID: 26064037 DOI: 10.1142/s1088424614500849] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A series of pegylated cis-A2B2- or A3B-type ZnPcs, substituted on the α-positions with tri(ethylene glycol) and hydroxyl groups, were synthesized from a new bis-phthalonitrile. A clamshell-type bis-phthalocyanine was also obtained as a byproduct. The hydroxyl group of one ZnPc was alkylated with 3-dimethylaminopropyl chloride to afford a pegylated ZnPc functionalized with an amine group. All mononuclear ZnPcs were soluble in polar organic solvents, showed intense Q absorptions in DMF, and had fluorescence quantum yields in the range 0.10-0.23. The clamshell-type bis-phthalocyanine adopts mainly open shell conformations in DMF, and closed clamshell conformations in chloroform. All ZnPcs were highly phototoxic to human carcinoma HEp2 cells, particularly the amino-ZnPc mainly protonated under physiological conditions, which showed the highest phototoxicity (IC50 = 0.5 μM at 1.5 J/cm2) and dark cytotoxicity (IC50 = 22 μM), in part due to its high cellular uptake. The ZnPcs localized in multiple organelles, including mitochondria, lysosomes, Golgi and ER.
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Affiliation(s)
- Benson G Ongarora
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Zehua Zhou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Elizabeth A Okoth
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Igor Kolesnichenko
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Kevin M Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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42
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Bhupathiraju NVSDK, Hu X, Zhou Z, Fronczek FR, Couraud PO, Romero IA, Weksler B, Vicente MGH. Synthesis and in vitro evaluation of BBB permeability, tumor cell uptake, and cytotoxicity of a series of carboranylporphyrin conjugates. J Med Chem 2014; 57:6718-28. [PMID: 25029034 PMCID: PMC4136688 DOI: 10.1021/jm500786c] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A series of tri[(p-carboranylmethylthio)tetrafluorophenyl]porphyrin conjugates of linear and branched polyamines, glucose, arginine, tri(ethylene glycol), and Tyr-D-Arg-Phe-β-Ala (YRFA) peptide were synthesized. These conjugates were investigated for their BBB permeability in human hCMEC/D3 brain endothelial cells, and their cytotoxicity and uptake were assessed using human glioma T98G cells. For comparison purposes, a symmetric tetra[(p-carboranylmethylthio)tetrafluorophenyl]porphyrin was also synthesized, and its crystal structure was obtained. All porphyrin conjugates show low dark cytotoxicity (IC50>400 μM) and low phototoxicity (IC50>100 μM at 1.5 J/cm2) toward T98G cells. All conjugates were efficiently taken up by T98G cells, particularly the cationic polyamine and arginine conjugates, and were localized in multiple cellular organelles, including mitochondria and lysosomes. All compounds showed relatively low in vitro BBB permeability compared with that of lucifer yellow because of their higher molecular weight, hydrophobicity, and tendency for aggregation in solution. Within this series, the branched polyamine and YRFA conjugates showed the highest permeability coefficient, whereas the glucose conjugate showed the lowest permeability coefficient.
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43
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Wang H, Vicente MGH, Fronczek FR, Smith KM. Synthesis and transformations of 5-chloro-2,2'-dipyrrins and their boron complexes, 8-chloro-BODIPYs. Chemistry 2014; 20:5064-74. [PMID: 24616111 PMCID: PMC4012389 DOI: 10.1002/chem.201304310] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Indexed: 11/09/2022]
Abstract
Symmetric dipyrrylketones 1 a,b were synthesized in two steps from the corresponding α-free pyrroles, by reaction with thiophosgene followed by oxidative hydrolysis under basic conditions. The dipyrrylketones produced the corresponding 5-chloro-dipyrrinium salts or 5-ethoxy-dipyrrins on reaction with phosgene or Meerwein's salt, respectively. Boron complexation of the dipyrrins afforded the corresponding 8-functionalized BODIPYs (borondipyrromethenes) in high yields. The 5-chloro-dipyrrinium salts reacted with methoxide or ethoxide ions to produce monopyrrole esters, presumably via a 5,5-dialkoxy-dipyrromethane intermediate. In contrast, 8-chloro-BODIPYs underwent a variety of nucleophilic substitutions of the chloro group in the presence of alkoxide ions, Grignard reagents, and thiols. In the presence of excess alkoxide or Grignard reagent, at room temperature or above, substitution at the boron center also occurred. The 8-chloro-BODIPY was a particularly useful reagent for the preparation of 8-aryl-, 8-alkyl-, and 8-vinyl-substituted BODIPYs in very high yields, using Pd(0) -catalyzed Stille cross-coupling reactions. The X-ray structures of eleven BODIPYs and two pyrroles are presented, and the spectroscopic properties of the synthesized BODIPYs are discussed.
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Affiliation(s)
- Haijun Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803 (USA), Fax: (+1) 225-578-3458
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803 (USA), Fax: (+1) 225-578-3458
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803 (USA), Fax: (+1) 225-578-3458
| | - Kevin M. Smith
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803 (USA), Fax: (+1) 225-578-3458
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44
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Jiao L, Wu Y, Wang S, Hu X, Zhang P, Yu C, Cong K, Meng Q, Hao E, Vicente MGH. Accessing near-infrared-absorbing BF2-azadipyrromethenes via a push-pull effect. J Org Chem 2014; 79:1830-5. [PMID: 24476041 DOI: 10.1021/jo402160b] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Novel aza-BODIPYs with significant bathochromic shifts were designed and synthesized by installation of strong electron-withdrawing groups on the para-positions of 1,7-phenyls and electron-donating groups on the para-positions of 3,4-phenyls. These dyes show strong NIR fluorescence emissions up to 756 nm, and absorptions up to 720 nm.
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Affiliation(s)
- Lijuan Jiao
- Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, School of Chemistry and Materials Science, Anhui Normal University , Wuhu, Anhui 241000, China
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45
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Giuntini F, Boyle R, Sibrian-Vazquez M, Graça H. Vicente M. Porphyrin Conjugates for Cancer Therapy. Handbook of Porphyrin Science (Volume 27) 2013. [DOI: 10.1142/9789814407755_0017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Francesca Giuntini
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, UK
| | - Ross Boyle
- Department of Chemistry, University of Hull, Kingston-upon-Hull, UK
| | | | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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Gibbs JH, Robins LT, Zhou Z, Bobadova-Parvanova P, Cottam M, McCandless GT, Fronczek FR, Vicente MGH. Spectroscopic, computational modeling and cytotoxicity of a series of meso-phenyl and meso-thienyl-BODIPYs. Bioorg Med Chem 2013; 21:5770-81. [PMID: 23928070 PMCID: PMC4133122 DOI: 10.1016/j.bmc.2013.07.017] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/02/2013] [Accepted: 07/09/2013] [Indexed: 01/07/2023]
Abstract
A series of twenty-two BODIPY compounds were synthesized, containing various meso-phenyl and meso-thienyl groups, and their spectroscopic and structural properties were investigated using both experimental and computational methods. Further functionalization of the BODIPY framework via iodination at the 2,6-pyrrolic positions was explored in order to determine the effect of these heavy atoms on the photophysical and cytotoxicity of the meso-aryl-BODIPYs. BODIPYs bearing meso-thienyl substituents showed the largest red-shifted absorptions and emissions and reduced fluorescence quantum yields. The phototoxicity of the BODIPYs in human carcinoma HEp2 cells depends on both the presence of iodines and the nature of the meso-aryl groups. Six of the eleven 2,6-diiodo-BODIPYs investigated showed at least a sevenfold enhancement in phototoxicity (IC50 = 3.5-28 μM at 1.5 J/cm(2)) compared with the non-iodinated BODIPYs, while the others showed no cytotoxicity, while their singlet oxygen quantum yields ranged from 0.02 to 0.76. Among the series investigated, BODIPYs 2a and 4a bearing electron-donating meso-dimethoxyphenyl substituents showed the highest phototoxicity and dark/phototoxicity ratio, and are therefore the most promising for application in PDT.
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Affiliation(s)
- Jaime H. Gibbs
- Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803, USA
| | - Larry T. Robins
- Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803, USA
| | - Zehua Zhou
- Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803, USA
| | | | - Michael Cottam
- Rockhurst University, Department of Chemistry, Kansas City, MO 64110, USA
| | | | - Frank R. Fronczek
- Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803, USA
| | - M. Graça H. Vicente
- Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803, USA
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47
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Pomarico G, Nardis S, Stefanelli M, Cicero DO, Vicente MGH, Fang Y, Chen P, Kadish KM, Paolesse R. Synthesis and Characterization of Functionalized meso-Triaryltetrabenzocorroles. Inorg Chem 2013; 52:8834-44. [DOI: 10.1021/ic4010467] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Giuseppe Pomarico
- Dipartimento di
Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica,
1, 00133 Rome, Italy
| | - Sara Nardis
- Dipartimento di
Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica,
1, 00133 Rome, Italy
| | - Manuela Stefanelli
- Dipartimento di
Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica,
1, 00133 Rome, Italy
| | - Daniel O. Cicero
- Dipartimento di
Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica,
1, 00133 Rome, Italy
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge,
Louisiana 70803, United States
| | - Yuanyuan Fang
- Department of Chemistry, University of Houston, Houston, Texas,
77204-5003 United States
| | - Ping Chen
- Department of Chemistry, University of Houston, Houston, Texas,
77204-5003 United States
| | - Karl M. Kadish
- Department of Chemistry, University of Houston, Houston, Texas,
77204-5003 United States
| | - Roberto Paolesse
- Dipartimento di
Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica,
1, 00133 Rome, Italy
- CNR IDASC, via Fosso del Cavaliere, 00133
Rome, Italy
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49
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Pomarico G, Nardis S, Naitana ML, Vicente MGH, Kadish KM, Chen P, Prodi L, Genovese D, Paolesse R. Aluminum, Gallium, Germanium, Copper, and Phosphorus Complexes of meso-Triaryltetrabenzocorrole. Inorg Chem 2013; 52:4061-70. [DOI: 10.1021/ic400162y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Giuseppe Pomarico
- Dipartimento di Scienze e Tecnologie
Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Rome,
Italy
| | - Sara Nardis
- Dipartimento di Scienze e Tecnologie
Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Rome,
Italy
| | - Mario L. Naitana
- Dipartimento di Scienze e Tecnologie
Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Rome,
Italy
| | - M. Graça H. Vicente
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Karl M. Kadish
- Department of Chemistry, University of Houston, Houston, Texas
77204-5003, United States
| | - Ping Chen
- Department of Chemistry, University of Houston, Houston, Texas
77204-5003, United States
| | - Luca Prodi
- Department of Chemistry, “G. Ciamician” Università di Bologna, 40126
Bologna, Italy
| | - Damiano Genovese
- Department of Chemistry, “G. Ciamician” Università di Bologna, 40126
Bologna, Italy
| | - Roberto Paolesse
- Dipartimento di Scienze e Tecnologie
Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Rome,
Italy
- CNR IDASC, via Fosso del Cavaliere, 00133 Rome, Italy
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50
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Sehgal I, Li H, Ongarora B, Devillier D, Vicente MGH. Synthesis and biological investigations of a ZnPc-antiCEA bioconjugate for imaging of colorectal cancer. J PORPHYR PHTHALOCYA 2013; 17:150-156. [PMID: 25328375 DOI: 10.1142/s108842461250143x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Two zinc(II) phthalocyanines (ZnPcs) were conjugated with a monoclonal antibody (MAb) directed against carcinoembryonic antigen (CEA), using an in situ activated carboxylic acid on the ZnPcs. The bioconjugate with the highest ZnPc/MAb ratio of 3 was investigated in vitro for its ability to target and fluorescently label human colorectal HT-29 cells. The ZnPc-CEA MAb 2 was observed to efficiently target HT-29 cells, about 37 times more than unconjugated ZnPc. Furthermore, in the presence of a 4-fold excess of unlabelled anti-CEA antibody, the fluorescence signal of 2 was reduced by ~90% showing that the targeting is CEA-mediated. These studies further confirm the high specificity of Pc-antibody conjugates for antigens over-expressed on tumor cells and warrant further investigations of these immunoconjugates and their derivatives for imaging of colorectal cancer.
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Affiliation(s)
- Inder Sehgal
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Hairong Li
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Benson Ongarora
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Daniel Devillier
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M Graça H Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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