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Viveros-Ceballos JL, Matías-Valdez LA, Sayago FJ, Cativiela C, Ordóñez M. New approaches towards the synthesis of 1,2,3,4-tetrahydro isoquinoline-3-phosphonic acid (Tic P). Amino Acids 2021; 53:451-459. [PMID: 33646426 DOI: 10.1007/s00726-021-02962-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 02/17/2021] [Indexed: 11/25/2022]
Abstract
Two new strategies for the efficient synthesis of racemic 1,2,3,4-tetrahydroisoquinoline-3-phosphonic acid (TicP) (±)-2 have been developed. The first strategy involves the electron-transfer reduction of the easily obtained α,β-dehydro phosphonophenylalanine followed by a Pictet-Spengler cyclization. The second strategy involves a radical decarboxylation-phosphorylation reaction on 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic). In both strategies, the highly electrophilic N-acyliminium ion is formed as a key intermediate, and the target compound is obtained in good yield using mild reaction conditions and readily available starting materials, complementing existing methodologies and contributing to the easy accessibility of (±)-2 for further research.
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Affiliation(s)
- José Luis Viveros-Ceballos
- Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, 62209, Cuernavaca, Morelos, Mexico.
| | - Lizeth A Matías-Valdez
- Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, 62209, Cuernavaca, Morelos, Mexico
| | - Francisco J Sayago
- Departamento de Química Orgánica, ISQCH, Universidad de Zaragoza, CSIC, 50009, Zaragoza, Spain
| | - Carlos Cativiela
- Departamento de Química Orgánica, ISQCH, Universidad de Zaragoza, CSIC, 50009, Zaragoza, Spain
| | - Mario Ordóñez
- Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, 62209, Cuernavaca, Morelos, Mexico.
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2
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Bumbak F, Thomas T, Noonan-Williams BJ, Vaid TM, Yan F, Whitehead AR, Bruell S, Kocan M, Tan X, Johnson MA, Bathgate RAD, Chalmers DK, Gooley PR, Scott DJ. Conformational Changes in Tyrosine 11 of Neurotensin Are Required to Activate the Neurotensin Receptor 1. ACS Pharmacol Transl Sci 2020; 3:690-705. [PMID: 32832871 PMCID: PMC7432660 DOI: 10.1021/acsptsci.0c00026] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Indexed: 12/12/2022]
Abstract
Cell-cell communication via endogenous peptides and their receptors is vital for controlling all aspects of human physiology and most peptides signal through G protein-coupled receptors (GPCRs). Disordered peptides bind GPCRs through complex modes for which there are few representative crystal structures. The disordered peptide neurotensin (NT) is a neuromodulator of classical neurotransmitters such as dopamine and glutamate, through activation of neurotensin receptor 1 (NTS1). While several experimental structures show how NT binds NTS1, details about the structural dynamics of NT during and after binding NTS1, or the role of peptide dynamics on receptor activation, remain obscure. Here saturation transfer difference (STD) NMR revealed that the binding mode of NT fragment NT10-13 is heterogeneous. Epitope maps of NT10-13 at NTS1 suggested that tyrosine 11 (Y11) samples other conformations to those observed in crystal structures of NT-bound NTS1. Molecular dynamics (MD) simulations confirmed that when NT is bound to NTS1, residue Y11 can exist in two χ1 rotameric states, gauche plus (g+) or gauche minus (g-). Since only the g+ Y11 state is observed in all the structures solved to date, we asked if the g- state is important for receptor activation. NT analogues with Y11 replaced with 7-OH-Tic were synthesized to restrain the dynamics of the side chain. P(OH-TIC)IL bound NTS1 with the same affinity as NT10-13 but did not activate NTS1, instead acted as an antagonist. This study highlights that flexibility of Y11 in NT may be required for NT activation of NTS1.
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Affiliation(s)
- Fabian Bumbak
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
- Bio21
Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Trayder Thomas
- Monash
Institute of Pharmaceutical Sciences, Monash
University, Parkville, Victoria 3052, Australia
| | - Billy J. Noonan-Williams
- Monash
Institute of Pharmaceutical Sciences, Monash
University, Parkville, Victoria 3052, Australia
| | - Tasneem M. Vaid
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
- Bio21
Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Fei Yan
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
- Bio21
Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Alice R. Whitehead
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Shoni Bruell
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Martina Kocan
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
- The School
of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Xuan Tan
- Department
of Chemistry, The University of Alabama
at Birmingham, Birmingham, Alabama 35294-1240, United States
| | - Margaret A. Johnson
- Department
of Chemistry, The University of Alabama
at Birmingham, Birmingham, Alabama 35294-1240, United States
| | - Ross A. D. Bathgate
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
| | - David K. Chalmers
- Monash
Institute of Pharmaceutical Sciences, Monash
University, Parkville, Victoria 3052, Australia
| | - Paul R. Gooley
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
- Bio21
Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Daniel J. Scott
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department
of Biochemistry and Molecular Biology, The
University of Melbourne, Parkville, Victoria 3010, Australia
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3
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Kotha S, Deodhar D, Khedkar P. Diversity-oriented synthesis of medicinally important 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) derivatives and higher analogs. Org Biomol Chem 2015; 12:9054-91. [PMID: 25299735 DOI: 10.1039/c4ob01446d] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
1,2,3,4-Tetrahydroisoquinoline-3-carboxylic acid (Tic) is a constrained analog of phenylalanine (Phe). The Tic unit has been identified as a core structural element present in several peptide-based drugs and forms an integral part of various biologically active compounds. This report covers the biological significance of the Tic core and provides a detailed account of various synthetic approaches available for the construction of Tic derivatives. Along with the traditional methods such as the Pictet-Spengler and Bischler-Nepieralski reactions, we cover various recent approaches such as enyne metathesis, [2 + 2 + 2] cycloaddition and the Diels-Alder reaction to generate Tic derivatives. In addition, syntheses of higher analogs of Tic are also discussed.
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Affiliation(s)
- Sambasivarao Kotha
- Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai - 400 076, India.
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4
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Maharani R, Sleebs BE, Hughes AB. Macrocyclic N-Methylated Cyclic Peptides and Depsipeptides. STUDIES IN NATURAL PRODUCTS CHEMISTRY 2015. [DOI: 10.1016/b978-0-444-63460-3.00004-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Kotha S, Goyal D, Chavan AS. Diversity-Oriented Approaches to Unusual α-Amino Acids and Peptides: Step Economy, Atom Economy, Redox Economy, and Beyond. J Org Chem 2013; 78:12288-313. [DOI: 10.1021/jo4020722] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Sambasivarao Kotha
- Department
of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai 400 076, India
| | - Deepti Goyal
- Department
of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai 400 076, India
| | - Arjun S. Chavan
- Department
of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai 400 076, India
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6
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Lee J, Currano JN, Carroll PJ, Joullié MM. Didemnins, tamandarins and related natural products. Nat Prod Rep 2012; 29:404-24. [PMID: 22270031 DOI: 10.1039/c2np00065b] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Since the discovery and isolation of the didemnin family of marine depsipeptides in 1981, the synthesis and biological activity of its congeners have been of great interest to the scientific community. The didemnins have demonstrated antitumor, antiviral, and immunosuppressive activity at low nano- and femtomolar levels. Of the congeners, didemnin B was the first marine natural product to reach phase II clinical trials in the United States, stimulating many analogue syntheses to date. About two decades later, tamandarins A and B were isolated, and were found to possess very similar structure and biological activity to that of the didemnin B. These compounds have shown impressive biological activity and some progress has been made in establishing structure-activity relationships. However, their molecular mechanism of action still remains unclear. This review highlights the long-standing study of didemnins and its critical application towards the understanding of the molecular mechanism of action of tamandarins and their potential use as therapeutic agents.
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Affiliation(s)
- Jisun Lee
- University of Pennsylvania, Department of Chemistry, Philadelphia, Pennsylvania, United States
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7
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Adrio J, Cuevas C, Manzanares I, Joullié MM. Total Synthesis and Biological Evaluation of Tamandarin B Analogues. J Org Chem 2007; 72:5129-38. [PMID: 17555353 DOI: 10.1021/jo070412r] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tamandarins A and B are a class of marine natural cyclodepsipeptides with structures and biological activities closely related to those of the didemnins. The easier synthetic access to tamandarins accelerates the preparation of new macrocyclic derivatives of this family of antitumor, antiviral, and immunosuppressive compounds. The optimization of the previously reported synthetic route to tamandarins by changing the macrolactamization site from Nst1 and Thr6 to Pro4 and N,O-Me2Tyr5 residues led to a significant improvement in the reaction yield. Using this new synthetic approach, four new macrocyclic analogues of tamandarin B were prepared and evaluated for anticancer activity. These results provide further insight into the structure-activity relationship of the tamandarins and didemnins.
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Affiliation(s)
- Javier Adrio
- Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
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8
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Adrio J, Cuevas C, Manzanares I, Joullié MM. Synthesis and biological evaluation of tamandarin B analogues. Org Lett 2006; 8:511-4. [PMID: 16435872 DOI: 10.1021/ol0530023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text]. The synthesis of two tamandarin B analogues in which the N,O-Me2Tyr5 unit was replaced by N-Me-phenylalanine (N-MePhe5) and (S)-2-(methylamino)-3-(naphthalen-2-yl)propanoic acid (N-MeNaphth5) is described. The choice of the macrocyclization site was crucial to achieve satisfactory macrolactamization. Coupling between norstatine (Nst1) and threonine (Thr6) afforded only a 15% yield, while lactamization between proline (Pro4) and the aromatic moiety could be achieved in 65% yield.
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Affiliation(s)
- Javier Adrio
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
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9
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Samnick S, Fozing T, Kirsch CM. Preparation and tumor affinity testing of the radioiodinated tetrahydroisoquinoline derivative [123I]TIC(OH) for targeting prostate cancer. Appl Radiat Isot 2006; 64:563-9. [PMID: 16426853 DOI: 10.1016/j.apradiso.2005.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 12/04/2005] [Accepted: 12/05/2005] [Indexed: 11/17/2022]
Abstract
This work describes the synthesis and tumor affinity testing of 8-[123I]iodo-l-1,2,3,4-tetrahydro-7-hydroxyisoquinoline-3-carboxylic acid [ITIC(OH)], a cyclic non-naturally occurring amino acid as an imaging probe for prostate cancer. Parameters for labelling were optimized with regard to the amount of precursor, the temperature and time. Thereafter, ITIC(OH) was evaluated in terms of its uptake in primary human PC-3 and DU-145 prostate cancer cells, followed by analysis of the underlying mechanisms of the radioactivity accumulation in tumor cells. No-carrier-added ITIC(OH) was obtained in 80+/-15% radiochemical yield and >98% radiochemical purity by a one-step radioiodination, using IODO-GEN as oxidant. The total synthesis time was less than 30 min, and compatible with a clinical routine production. ITIC(OH) accumulated intensively in primary human prostate cancer cells. The radioactivity incorporation in tumor following a 10-min incubation at 37 degrees C/pH 7.4 varied from 35% to 58% of the total loaded activity per 10(6) tumor cells (355-540 cpm/1000 cells). Inhibition experiments revealed that ITIC(OH) was taken up into tumor by an active transport different from the common amino acid carrier systems, including the sodium-dependent system A and B+,0, and the sodium-independent L- and ASC-type transporter. In contrast, the cellular incorporation was dependent on the membrane potential and correlated with the activity of the mitochondria. In conclusion, the specific and high-level accumulation of ITIC(OH) in human prostate carcinoma cells, indicates that the new radiopharmaceutical is a good candidate for further in vivo investigations to ascertain its potential as an imaging probe for prostate cancer by SPET.
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Affiliation(s)
- Samuel Samnick
- Department of Nuclear Medicine, Saarland University Medical Center, D-66421 Homburg, Germany.
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10
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Vera MD, Joullié MM. Natural products as probes of cell biology: 20 years of didemnin research. Med Res Rev 2002; 22:102-45. [PMID: 11857636 DOI: 10.1002/med.10003] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The discovery of the didemnin family of marine depsipeptides launched an exciting and intriguing chapter in natural product chemistry. The unusual structure of the didemnin congeners has led to several total syntheses by research groups from around the world. The impressive in vitro and in vivo biological activities of the didemnins resulted in the first human clinical trials in the U.S. of a marine natural product against cancer, and additional clinical trials of a second-generation didemnin, dehydrodidemnin B (aplidine), are underway. As we mark the 20-year anniversary of the discovery of the didemnins, this class of natural products continues to stimulate active research in fields ranging from synthetic and medicinal chemistry to clinical oncology and cell biology. While some progress was made in dissecting the molecular mechanism of action and in establishing structure-activity relationships, there are still more questions than answers. This review covers the recent didemnin literature, highlighting the work directed towards understanding how this group of natural products interact with fundamental processes such as cell proliferation, protein biosynthesis, and apoptosis. The didemnin field illustrates how natural product chemistry may be used as a critical tool for the study of cell biology.
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Affiliation(s)
- Matthew D Vera
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA
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11
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Tarver JE, Pfizenmayer AJ, Joullié MM. Total syntheses of conformationally constrained didemnin B analogues. replacements of N,O-dimethyltyrosine with L-1,2,3,4-tetrahydroisoquinoline and L-1,2,3,4-tetrahydro-7-methoxyisoquinoline. J Org Chem 2001; 66:7575-87. [PMID: 11701008 DOI: 10.1021/jo0105991] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The design and synthesis of two conformationally constrained analogues of didemnin B are described. The [N,O-Me(2)Tyr(5)]residue of didemnin B was replaced with L-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) and L-1,2,3,4-tetrahydro-7-methoxyisoquinoline-3-carboxylic acid (MeO-Tic), which mimic the N,O-dimethylated tyrosine while constraining the conformation of the molecule. Preliminary results indicate that the conformation of the [N,O-Me(2)Tyr(5)]residue closely matches the conformation imposed by the Tic replacement.
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Affiliation(s)
- J E Tarver
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA
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12
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Liang B, Richard DJ, Portonovo PS, Joullié MM. Total syntheses and biological investigations of tamandarins A and B and tamandarin A analogs. J Am Chem Soc 2001; 123:4469-74. [PMID: 11457232 DOI: 10.1021/ja010222c] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tamandarins A (1) and B (2), two natural products similar in structure to didemnin B (3), were recently isolated from a Brazilian marine ascidian of the family Didemnidae. The cytotoxicity of 1 was reported to be somewhat more potent in vitro than that of 3 against various human cancer cell lines. The present account describes the first total syntheses of 1 and 2, and the syntheses of tamandarin A side chain analogues. The cytotoxicity data for these compounds show that the side chain modifications exhibit a parallel effect for both didemnins and tamandarins. This observation supports tamandarins' role as didemnins' mimic.
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Affiliation(s)
- B Liang
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
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13
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Xiao D, Vera MD, Liang B, Joullié MM. Total synthesis of a conformationally constrained didemnin B analog. J Org Chem 2001; 66:2734-42. [PMID: 11304195 DOI: 10.1021/jo001640n] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The total synthesis of a didemnin B analogue containing a conformationally constrained replacement for the isostatine moiety is reported. Synthetic highlights include an improved preparation of 2-hydroxy-3-cyclohexenecarboxylic acid and a new strategy for accessing the macrocycle.
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Affiliation(s)
- D Xiao
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104-6323, USA
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14
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Samnick S, Schaefer A, Siebert S, Richter S, Vollmar B, Kirsch CM. Preparation and investigation of tumor affinity, uptake kinetic and transport mechanism of iodine-123-labelled amino acid derivatives in human pancreatic carcinoma and glioblastoma cells. Nucl Med Biol 2001; 28:13-23. [PMID: 11182560 DOI: 10.1016/s0969-8051(00)00176-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In developing radioiodinated agents for pancreatic and brain tumor imaging by single photon emission tomography (SPET), we prepared p-amino-3-[123I]iodo-l-phenylalanine (IAPA), p-[123I]iodo-l-phenylalanine (IPA), L-8-[123I]iodo-1,2,3,4-tetrahydro-7-hydroxyisoquinoline-3-carboxylic acid (ITIC) and L-3-[123I]iodo-alpha-methyl-tyrosine (IMT) in radiochemical yields up to 95%, and we investigated their uptake in human pancreatic carcinoma and glioblastoma cells as well as the mechanisms promoting the tumor uptake. The radiopharmaceutical uptake into tumor cells was rapid (t(1/2) < or = 5 min) and temperature- and pH-dependent. The radioactivity concentration in tumor cells varied from 10 to 33% of the total activity (105-310 cpm/1000 cells) following a 30-min incubation at 37 degrees C (pH 7.4). In comparison, accumulation of the radiopharmaceuticals into normal brain and pancreatic tissue remained relatively low. Depolarizing the plasma membrane potential in high K+ buffer significantly altered the radioactivity concentration in the tumor cells, suggesting that membrane potential plays a certain role in the cellular uptake. Competitive inhibition experiments with specific amino acid transport inhibitors indicated that the uptake of IAPA, IPA and IMT into human pancreatic carcinoma and glioblastoma cells is predominantly mediated by the L and ASC transport systems, while no substantial involvement of the transport system A in their tumor uptake could be demonstrated. In contrast, results of the present investigation indicated that ITIC is not taken up into tumor cells via the common neutral amino acid carrier systems, including the A, L and ASC system. Furthermore, preloading with naturally occurring L-amino acids failed to stimulate the cellular uptake of the radiopharmaceuticals. These data indicate that the investigated radiopharmaceuticals exhibit interesting characteristics with promise for in vivo tumor investigations to ascertain their potential as radioligands for glioma and pancreatic carcinoma imaging by SPET.
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Affiliation(s)
- S Samnick
- Department of Nuclear Medicine, Institute of Clinical and Experimental Surgery, Saarland University Hospital Center, D-66421, Homburg/Saar, Germany.
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15
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Ahuja D, Geiger A, Ramanjulu JM, Vera MD, SirDeshpande B, Pfizenmayer A, Abazeed M, Krosky DJ, Beidler D, Joullié MM, Toogood PL. Inhibition of protein synthesis by didemnins: cell potency and SAR. J Med Chem 2000; 43:4212-8. [PMID: 11063617 DOI: 10.1021/jm000168v] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Synthetic and naturally occurring didemnins are potent and specific inhibitors of protein synthesis in vitro. Structure-activity analysis indicates a requirement for the intact macrocycle; however, the smaller ring size represented by the didemnin analogue, tamandarin A, is equipotent to didemnin B. Replacement of the N,O-dimethyltyrosine by a N-methylphenylalanine or N-methylleucine residue is also well-tolerated. The rank order for inhibition of protein synthesis in vitro appears to be retained in MCF-7 cells, albeit at much higher potency. This increase in potency is explained for the first time by data indicating that MCF-7 cells can accumulate didemnin B up to 2-3 orders of magnitude compared to the growth medium.
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Affiliation(s)
- D Ahuja
- Willard H. Dow Laboratory, Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA
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16
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Brózda D, Koroniak Ł, Rozwadowska MD. Stereoselective synthesis of 3-mono- and 1,3-disubstituted 4-phenyl-1,2,3,4-tetrahydroisoquinolines. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0957-4166(00)00258-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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