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Lin TC, Chan CK, Chung YH, Wang CC. Environmentally friendly Nafion-catalyzed synthesis of 3-substituted isoquinoline by using hexamethyldisilazane as a nitrogen source under microwave irradiation. Org Biomol Chem 2023; 21:7316-7326. [PMID: 37531171 DOI: 10.1039/d3ob01032e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
This study developed an eco-friendly method to synthesize 3-arylisoquinoline from 2-alkynylbenzaldehydes using Nafion® NR50 as an acidic catalyst and hexamethyldisilazane (HMDS) as a nitrogen source. The reaction proceeded via a 6-exo-dig cyclization under microwave irradiation, giving the corresponding isoquinolines in excellent yields. The advantages of this protocol include: (1) the use of recyclable acid catalysts, (2) transition-metal-free catalysis, and (3) the effective formation of the target product. These features make this methodology a promising approach for the sustainable and efficient synthesis of 3-arylisoquinoline. Some structures were also confirmed by single-crystal X-ray diffraction analysis.
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Affiliation(s)
- Tzu-Chun Lin
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
| | - Chieh-Kai Chan
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
| | - Yi-Hsiu Chung
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
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2
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Vinoth P, Karuppasamy M, Gupta A, Nagarajan S, Maheswari CU, Sridharan V. Intramolecular oxypalladation-initiated domino sequence: One-pot, two-step regioselective synthesis of isoquinolines. Tetrahedron 2023. [DOI: 10.1016/j.tet.2023.133272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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3
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Lukasevics L, Cizikovs A, Grigorjeva L. Cobalt-catalyzed C(sp 2)-H bond imination of phenylalanine derivatives. Chem Commun (Camb) 2022; 58:9754-9757. [PMID: 35959660 DOI: 10.1039/d2cc02334b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein we report the cobalt-catalyzed, picolinamide-directed C-H bond imination protocol of phenylalanine derivatives using isocyanides and a Co(dpm)2 catalyst. A wide range of functional groups were tolerated under the reaction conditions, yielding imines in high yields. The obtained imine products can easily be transformed to 1-aminoisoquinoline derivatives under reductive conditions, providing an attractive alternative to already existing methodologies. The control experiments indicated that C-H activation might occur via an electrophilic pathway.
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Affiliation(s)
- Lukass Lukasevics
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia. .,Faculty of Materials Science and Applied Chemistry, Riga Technical University, P. Valdena Street 3, Riga, LV-1048, Latvia
| | - Aleksandrs Cizikovs
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia.
| | - Liene Grigorjeva
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia.
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4
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Sun JG, Zhang XY, Yang H, Li P, Zhang B. Highly Regioselective Isoquinoline Synthesis via Nickel-Catalyzed Iminoannulation of Alkynes at Room Temperature. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800341] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jian-Guo Sun
- State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjia Xiang 210009 Nanjing China
| | - Xiao-Yu Zhang
- State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjia Xiang 210009 Nanjing China
| | - Hua Yang
- State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjia Xiang 210009 Nanjing China
| | - Ping Li
- State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjia Xiang 210009 Nanjing China
| | - Bo Zhang
- State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjia Xiang 210009 Nanjing China
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5
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Hachiya I, Mizota I, Shimizu M. New Synthetic Reactions Using the Iodotitanation Ability of Titanium Tetraiodide. J SYN ORG CHEM JPN 2017. [DOI: 10.5059/yukigoseikyokaishi.75.1226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | | | - Makoto Shimizu
- Department of Chemistry for Materials, Graduate School of Engineering, Mie University
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Qi L, Hu K, Yu S, Zhu J, Cheng T, Wang X, Chen J, Wu H. Tandem Addition/Cyclization for Access to Isoquinolines and Isoquinolones via Catalytic Carbopalladation of Nitriles. Org Lett 2016; 19:218-221. [DOI: 10.1021/acs.orglett.6b03499] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Linjun Qi
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Kun Hu
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Shuling Yu
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Jianghe Zhu
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Tianxing Cheng
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Xiaodong Wang
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Jiuxi Chen
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
| | - Huayue Wu
- College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, P. R. China
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7
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Rouchet JBEY, Schneider C, Fruit C, Hoarau C. Regioselective decarboxylative cross-coupling of carboxy isoquinoline N-oxides. J Org Chem 2015; 80:5919-27. [PMID: 25938169 DOI: 10.1021/acs.joc.5b00475] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A straightforward method for direct decarboxylative arylation of 1- and 3-carboxy isoquinaldic acid N-oxides with aryl iodides is reported. The reaction proceeded selectively at the carboxy function site to exclusively give the corresponding C-1 or C-3 arylated product. This methodology tolerates various aryl iodides substituted by electronically different groups. Combined with subsequent Reissert-Henze chlorination and SNAr amination, the decarboxylative arylation provides an efficient access to 1,3-functionalized isoquinoline-based antitumor agent.
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Affiliation(s)
- Jean-Baptiste E Y Rouchet
- Normandie University, COBRA, UMR 6014 et FR 3038, University Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, Mont-Saint-Aignan 76821 Cedex, France
| | - Cédric Schneider
- Normandie University, COBRA, UMR 6014 et FR 3038, University Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, Mont-Saint-Aignan 76821 Cedex, France
| | - Corinne Fruit
- Normandie University, COBRA, UMR 6014 et FR 3038, University Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, Mont-Saint-Aignan 76821 Cedex, France
| | - Christophe Hoarau
- Normandie University, COBRA, UMR 6014 et FR 3038, University Rouen, INSA Rouen, CNRS, IRCOF, 1 rue Tesnière, Mont-Saint-Aignan 76821 Cedex, France
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8
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Khadka DB, Woo H, Yang SH, Zhao C, Jin Y, Le TN, Kwon Y, Cho WJ. Modification of 3-arylisoquinolines into 3,4-diarylisoquinolines and assessment of their cytotoxicity and topoisomerase inhibition. Eur J Med Chem 2015; 92:583-607. [PMID: 25613224 DOI: 10.1016/j.ejmech.2015.01.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 01/06/2015] [Accepted: 01/08/2015] [Indexed: 01/29/2023]
Abstract
Inspired by the initial success of the monoarylisoquinolines and the quest to identify more potent and selective anticancer agents with topoisomerase (topo) inhibitory activity, series of diarylisoquinolines (3,4-diarylisoquinolones and 3,4-diarylisoquinolinamines) were designed and synthesized. Synthesis of these compounds primarily involved lithiated toluamide-benzonitrile cycloaddition, Suzuki coupling, and nucleophilic aromatic substitution reactions. Eight of the derivatives were selectively toxic against human ductal breast epithelial tumor cells (T47D), human prostate cancer cells (DU145), and human colorectal adenocarcinoma cells (HCT-15), but had no effect on normal human breast epithelial cells (MCF10A). The topo inhibitory activities of the diarylisoquinoline compounds were relatively dependent upon their chemical structure. 3,4-Diarylisoquinolones generally did not inhibit topo I and only showed moderate inhibition of topo II. In contrast, several 3,4-diarylisoquinolinamines showed superior topo I inhibitory activity. Isoquinolinamine derivatives had greater affinity for topo I than for topo II. Topo inhibition by 3,4-diarylisoquinolines was further supported by docking models showing intercalative and/or H-bond interactions between these compounds and the DNA/topo(s). An analysis of the correlation between the cytotoxicity and topo inhibition of these compounds indicated that the primary biological target of derivatives with potent cytotoxicity was topo, which in turn establishes diaryl-substituted isoquinolines as a novel class of potential anticancer drugs.
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Affiliation(s)
- Daulat Bikram Khadka
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Hyunjung Woo
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top 5 Program, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Su Hui Yang
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Chao Zhao
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Yifeng Jin
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Thanh Nguyen Le
- Center for Drug Research and Development, Institute of Marine Biochemistry, Vietnam Academy of Science and Technology, 18-Hoang Quoc Viet, Caugiay, Hanoi, Vietnam
| | - Youngjoo Kwon
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top 5 Program, Ewha Womans University, Seoul 120-750, Republic of Korea.
| | - Won-Jea Cho
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea.
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Niemczak M, Czerniak K, Kopczyński T. Preparation of 1-methyl-3-phenylisoquinoline derivatives from oximes using polyphosphoric esters. NEW J CHEM 2015. [DOI: 10.1039/c4nj02075h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1-Methyl-3-phenylisoquinoline derivatives were synthesized with high efficiency from oximesviaBeckmann rearrangement, isomerization and condensation, all promoted by polyphosphate ester.
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Affiliation(s)
- Michał Niemczak
- Department of Chemical Technology
- Poznan University of Technology
- 60-965 Poznan
- Poland
| | - Kamil Czerniak
- Department of Chemical Technology
- Poznan University of Technology
- 60-965 Poznan
- Poland
| | - Tomasz Kopczyński
- Department of Chemical Technology
- Poznan University of Technology
- 60-965 Poznan
- Poland
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10
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Design, synthesis and systematic evaluation of cytotoxic 3-heteroarylisoquinolinamines as topoisomerases inhibitors. Eur J Med Chem 2014; 82:181-94. [DOI: 10.1016/j.ejmech.2014.05.047] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 05/13/2014] [Accepted: 05/20/2014] [Indexed: 02/05/2023]
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11
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Tropsha A, Golbraikh A, Cho WJ. Development of kNN QSAR Models for 3-Arylisoquinoline Antitumor Agents. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.7.2397] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Le TN, Yang SH, Khadka DB, Van HTM, Cho SH, Kwon Y, Lee ES, Lee KT, Cho WJ. Design and synthesis of 4-amino-2-phenylquinazolines as novel topoisomerase I inhibitors with molecular modeling. Bioorg Med Chem 2011; 19:4399-404. [DOI: 10.1016/j.bmc.2011.05.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 05/06/2011] [Accepted: 05/07/2011] [Indexed: 12/30/2022]
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13
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Khadka DB, Cho WJ. 3-Arylisoquinolines as novel topoisomerase I inhibitors. Bioorg Med Chem 2011; 19:724-34. [DOI: 10.1016/j.bmc.2010.10.057] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 10/27/2010] [Accepted: 10/28/2010] [Indexed: 12/22/2022]
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14
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Yang T, Cui FD, Choi MK, Cho JW, Chung SJ, Shim CK, Kim DD. Enhanced solubility and stability of PEGylated liposomal paclitaxel: In vitro and in vivo evaluation. Int J Pharm 2007; 338:317-26. [PMID: 17368984 DOI: 10.1016/j.ijpharm.2007.02.011] [Citation(s) in RCA: 312] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 01/15/2007] [Accepted: 02/09/2007] [Indexed: 12/13/2022]
Abstract
An improved PEGylated liposomal formulation of paclitaxel has been developed with the purpose of improving the solubility of paclitaxel as well as the physicochemical stability of liposome in comparison to the current Taxol formulation. The use of 3% (v/v) Tween 80 in the hydration media was able to increase the solubility of drug. The addition of sucrose as a lyoprotectant in the freeze-drying process increased the stability of the liposome particles. There was no significant difference in the entrapment efficiency of paclitaxel between the conventional non-PEGylated liposomes and our PEGylated liposomes. Cytotoxicity in human breast cancer cell lines (MDA-MB-231 and SK-BR-3) of our paclitaxel formulation was less potent compared to Taxol after 24h incubation, but was equipotent after 72 h due to the slower release of drug from the liposome. Our PEGylated liposomes increased the biological half-life of paclitaxel from 5.05 (+/-1.52)h to 17.8 (+/-2.35)h compared to the conventional liposomes in rats. Biodistribution studies in breast cancer xenografted nude mouse model showed that our liposomes significantly decreased the uptake in reticuloendothelial system (RES)-containing organs (liver, spleen and lung) while increasing the uptake in tumor tissues after injection compared to Taxol or the conventional liposomal formulation. Moreover, the PEGylated liposome showed greater tumor growth inhibition effect in in vivo studies. Therefore, our PEGylated liposomal formulation of paclitaxel could serve as a better alternative for the passive targeting of human breast tumors.
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Affiliation(s)
- Tao Yang
- College of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
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15
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Yang T, Choi MK, Cui FD, Kim JS, Chung SJ, Shim CK, Kim DD. Preparation and evaluation of paclitaxel-loaded PEGylated immunoliposome. J Control Release 2007; 120:169-77. [PMID: 17586082 DOI: 10.1016/j.jconrel.2007.05.011] [Citation(s) in RCA: 180] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2006] [Revised: 04/18/2007] [Accepted: 05/05/2007] [Indexed: 11/26/2022]
Abstract
A sterically stabilized paclitaxel-loaded liposome tailored to target human breast cancer cells was developed, thereby promoting the efficiency of intracellular delivery of paclitaxel through receptor-mediated endocytosis. Results indicated that the targeting moiety (thiolated Herceptin) was successfully coupled to the distal reactive maleimide terminus of the poly (ethylene glycol)-phospholipid conjugate as well as being incorporated in the liposomal bilayers. The particle size of the PEGylated immunoliposome was maintained at about 200 nm. Confocal microscopy studies showed that the PEGylated immunoliposome was uptaken into the interior of the tumor cell through the receptor-mediated endocytosis pathway. The PEGylated immunoliposome showed substantially higher cellular uptake than the PEGylated liposome in cancer cells (BT-474 and SK-BR-3) over-expressing human epidermal growth factor receptor 2 (HER2) at 37 degrees C, while no difference was found in low HER2 expressing cells (MDA-MB-231) nor at low temperature (4 degrees C). Pharmacokinetics of paclitaxel in the PEGylated immunoliposome was compared with that in Taxol and in the PEGylated liposome in rats. The circulating time of paclitaxel in the PEGylated immunoliposome was prolonged compared to Taxol while slightly shortened than that in the PEGylated liposome. Therefore, the paclitaxel-loaded PEGylated immunoliposome using Herceptin could serve as a promising model for future tumor specific cancer therapy of HER2 over-expressing breast cancers.
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Affiliation(s)
- Tao Yang
- College of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
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Cho WJ, Min SY, Le TN, Kim TS. Synthesis of new 3-Arylisoquinolinamines: effect on topoisomerase I inhibition and cytotoxicity. Bioorg Med Chem Lett 2003; 13:4451-4. [PMID: 14643344 DOI: 10.1016/j.bmcl.2003.09.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To investigate the structure-activity relationships of 3-arylisoquinolines, diverse substituted 3-aryisoquinolinamines were synthesized and tested in vitro antitumor activity against four tumor cell lines. Some of the compounds showed potent topoisomerase I inhibitory activity. Docking study of 7d with topoisomerase I-DNA complex was also performed.
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Affiliation(s)
- Won-Jea Cho
- College of Pharmacy, Chonnam National University, Yong-Bong dong, Buk-gu, Kwangju 500-757, South Korea.
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Cho WJ, Kim EK, Park IY, Jeong EY, Kim TS, Le TN, Kim DD, Lee ES. Molecular modeling of 3-arylisoquinoline antitumor agents active against A-549. A comparative molecular field analysis study. Bioorg Med Chem 2002; 10:2953-61. [PMID: 12110317 DOI: 10.1016/s0968-0896(02)00137-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A series of 58 3-arylisoquinoline antitumor agents were investigated for defining the pharmacophore model using comparative molecular field analysis (CoMFA) program. The studied compounds related to bioisostere of benzophenanthridine alkaloid were synthesized and evaluated for antitumor cytotoxicity against human lung tumor cell (A 549). In order to perform the systematic molecular modeling study of these compounds, the conformational search was carried out based on the single X-ray crystallographic structure of 7,8-dimethoxy-3-phenylisoquinolin-(2H)-one (2). Interestingly, two types of structures having different dihedral angles between the isoquinoline ring and 3-aryl ring were found in the crystals. Therefore, CoMFA was performed two different, overlapping ways. The alignments of the structures were based on the common isoquinoline ring and 3-aryl ring. The 3-D-quantitative structure-activity relationship study resulted in significant cross-validated, conventional r(2) values equal to 0.715 and 0.927, respectively.
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Affiliation(s)
- Won-Jea Cho
- College of Pharmacy, Chonnam National University, Yongbong-dong Buk-gu, Kwangju 500-757, Republic of Korea.
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Kim KE, Cho WJ, Kim TS, Kang BH, Chang SJ, Lee CH, Kim DD. Physicochemical properties of CWJ-a-5, a new antitumor 3-arylisoquinoline derivative. Drug Dev Ind Pharm 2002; 28:889-95. [PMID: 12236074 DOI: 10.1081/ddc-120005634] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The compound CWJ-a-5 [1-(4-methylpiperazinyl)-3-phenylisoquinoline hydrochloride] is a novel 3-arylisoquinoline derivative which has exhibited potent antitumor activity. As part of an effort to develop a useful formulation for clinical evaluation of this compound, the aqueous stability of CWJ-a-5 as a function of pH, ionic strength, and temperature, as well as its various physicochemical properties, have been examined. The pKa value obtained by potentiometric titration in methanol-water mixtures was 3.61, at 25 degrees C. The aqueous solubility and the apparent partition coefficient of CWJ-a-5 over the pH range 2.08-9.88 were consistent with those expected of a weak acid of similar pKa value. The degradation of CWJ-a-5 was found to follow apparent first-order kinetics. The pH-rate profiles generated at 80 degrees C were accounted for by acid-catalyzed degradation at low pH and base-catalyzed degradation at high pH. The activation energy was determined as 22.12 kcal/mol for the degradation of CWJ-a-5 in a pH 2.92 solution with a constant ionic strength of 0.2. Increasing the ionic strength up to 0.9 led to a higher degradation rate constant at pH 2.92. However, CWJ-a-5 was very stable even in a pH 2.92 solution, and its shelf-life was calculated to be 2.03 years at 25 degrees C from the Arrhenius plot.
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Affiliation(s)
- Ki-Eun Kim
- College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
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