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Chen JW, Wu QH, Rowley DC, Al-Kareef AMQ, Wang H. Anticancer agent-based marine natural products and related compounds. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2015; 17:199-216. [PMID: 25559315 DOI: 10.1080/10286020.2014.996140] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 12/03/2014] [Indexed: 06/04/2023]
Abstract
Marine natural products constitute a huge reservoir of anticancer agents. Consequently during the past decades, several marine anticancer compounds have been isolated, identified, and approved for anticancer treatment or are under trials. In this article the sources, structure, bioactivities, mode of actions, and analogs of some promising marine and derived anticancer compounds have been discussed.
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Affiliation(s)
- Jian-Wei Chen
- a College of Pharmaceutical Science, Zhejiang University of Technology , Hangzhou 310014 , P.R. China
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2
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A review of the effect of multiple conformers on crystallization from solution and strategies for crystallizing slow inter-converting conformers. Chem Eng Sci 2014. [DOI: 10.1016/j.ces.2013.11.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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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: 57] [Impact Index Per Article: 4.8] [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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4
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Abstract
Abstract
Patterson search is a powerful tool for solving difficult crystal structures since it actively uses chemical information. Our program PATSEE, which attempts to combine the merits of Patterson and direct methods in order to locate a fragment with known geometry in the unit cell, has solved a large number of crystal structures during the last decade and proved to be reliable and widely applicable. We have tested PATSEE successfully on 20 structures of different size and complexity contained in a test data bank using fragments either taken from related crystal structures or calculated by force-field methods. Even structures with several torsional degrees of freedom (like those of oligopeptides) could be solved convincingly. As a result, general experiences – such as requirements for the minimum size and the accuracy of a search fragment, the reliability of the various figures of merit, the chances to locate single atoms and to tackle larger structures – were gained, which should help in finding an optimum strategy for the solution of problem structures with PATSEE.
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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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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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7
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Seebach D, Ko SY, Kessler H, Köck M, Reggelin M, Schmieder P, Walkinshaw MD, Bölsterli JJ, Bevec D. Thiocyclosporins: Preparation, Solution and Crystal Structure, and Immunosuppressive Activity. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19910740833] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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8
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Gutiérrez-Rodríguez M, Martín-Martínez M, García-López MT, Herranz R, Cuevas F, Polanco C, Rodríguez-Campos I, Manzanares I, Cárdenas F, Feliz M, Lloyd-Williams P, Giralt E. Synthesis, Conformational Analysis, and Cytotoxicity of Conformationally Constrained Aplidine and Tamandarin A Analogues Incorporating a Spirolactam β-Turn Mimetic. J Med Chem 2004; 47:5700-12. [PMID: 15509169 DOI: 10.1021/jm040788m] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
With the aim of studying the contribution of the beta II turn conformation at the side chain of didemnins to the bioactive conformation responsible for their antitumoral activity, conformationally restricted analogues of aplidine and tamandarin A, where the side chain dipeptide Pro8-N-Me-d-Leu7 is replaced with the spirolactam beta II turn mimetic (5R)-7-[(1R)-1-carbonyl-3-methylbutyl]-6-oxo-1,7-diazaspiro[4.4]nonane, were prepared. Additionally, restricted analogues, where the aplidine (pyruvyl9) or tamandarin A [(S)-Lac9] acyl groups are replaced with the isobutyryl, Boc, and 2-methylacryloyl groups, were also prepared. These structural modifications were detrimental to cytotoxic activity, leading to a decrease of 1-2 orders of magnitude with respect to that exhibited by aplidine and tamandarin A. The conformational analysis of one of these spirolactam aplidine analogues, by NMR and molecular modeling methods, showed that the conformational restriction caused by the spirolactam does not produce significant changes in the overall conformation of aplidine, apart from preferentially stabilizing the trans rotamer at the pyruvyl9-spirolactam amide bond, whereas in aplidine both cis and trans rotamers at the pyruvyl9-Pro8 amide bond are more or less equally stabilized. These results seem to indicate a preference for the cis form at that amide bond in the bioactive conformation of aplidine. The significant influence of this cis/trans isomerism upon the cytotoxicity suggests a possible participation of a peptidylprolyl cis/trans isomerase in the mechanism of action of aplidine.
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Marco E, Martín-Santamaría S, Cuevas C, Gago F. Structural basis for the binding of didemnins to human elongation factor eEF1A and rationale for the potent antitumor activity of these marine natural products. J Med Chem 2004; 47:4439-52. [PMID: 15317456 DOI: 10.1021/jm0306428] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Didemnins and tamandarins are closely related marine natural products with potent inhibitory effects on protein synthesis and cell viability. On the basis of available biochemical and structural evidence and results from molecular dynamics simulations, a model is proposed that accounts for the strong and selective binding of these compounds to human elongation factor eEF1A in the presence of GTP. We suggest that the p-methoxyphenyl ring of these cyclic depsipeptides is inserted into the same pocket in eEF1A that normally lodges either the 3' terminal adenine of aminoacylated tRNA, as inferred from two prokaryotic EF-Tu.GTP.tRNA complexes, or the aromatic side chain of Phe/Tyr-163 from the nucleotide exchange factor eEF1Balpha, as observed in several X-ray crystal structures of a yeast eEF1A:eEF1Balpha complex. This pocket, which has a strong hydrophobic character, is formed by two protruding loops on the surface of eEF1A domain 2. Further stabilization of the bound depsipeptide is brought about by additional crucial interactions involving eEF1A domain 1 in such a way that the molecule fits snugly at the interface between these two domains. In the GDP-bound form of eEF1A, this binding site exists only as two separate halves, which accounts for the much greater affinity of didemnins for the GTP-bound form of this elongation factor. This binding mode is entirely different from those seen in the complexes of the homologous prokaryotic EF-Tu with kirromycin-type antibiotics or the cyclic thiazolyl peptide antibiotic GE2270A. Interestingly, the set of interactions used by didemnins to bind to eEF1A is also distinct from that used by eEF1Balpha or eEF1Bbeta, thus establishing a competition for binding to a common site that goes beyond simple molecular mimicry. The model presented here is consistent with both available biochemical evidence and known structure-activity relationships for these two classes of natural compounds and synthetic analogues and provides fertile ground for future research.
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Affiliation(s)
- Esther Marco
- Departamento de Farmacología, Universidad de Alcalá, E-28871 Alcalá de Henares, Madrid, Spain
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10
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Gutiérrez-Rodrı́guez M, Garcı́a-López M, Herranz R. Improved synthesis of a [4.4]-spirolactam β-turn mimetic as surrogate of the didemnin side chain dipeptide Pro-N-Me-d-Leu. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.04.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Cárdenas F, Caba JM, Feliz M, Lloyd-Williams P, Giralt E. Analysis of Conformational Equilibria in Aplidine Using Selective Excitation 2D NMR Spectroscopy and Molecular Mechanics/Dynamics Calculations. J Org Chem 2003; 68:9554-62. [PMID: 14656079 DOI: 10.1021/jo034798r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aplidine (dehydrodidemnin B), a natural product with potent antitumor activity currently in multicenter phase II clinical trials, exists in DMSO as a mixture of four slowly interconverting conformations in a ratio of 47:33:13:7. NMR spectroscopy shows that these arise as a consequence of cis/trans isomerization about the NMe-Leu(7)-Pro(8) and Pro(8)-Pyr amide bonds of the molecule's side chain. Two major conformations account for 47% and 33% of the total population, a ratio of 60:40 between the two. They correspond to the cis- and trans-isomers, respectively, about the Pro(8)-Pyr amide bond. Two minor conformers arise as a consequence of similar isomerism about the Pro(8)-Pyr amide bond, but in structures in which the NMe-Leu(7)-Pro(8) amide bond is cis rather than trans. These account for approximately 13% and 7% of the total population, corresponding to a ratio of 65:35 cis/trans, respectively. Molecular dynamics simulations show that the three-dimensional structures of all four conformational isomers are similar in the macrocycle and that all are essentially unchanged with respect to the macrocycle of didemnin B. Significant differences in the conformation of the molecule's side chain are, however, observed between major and minor pairs. Analysis of hydrogen-bonding patterns shows that each major conformer exhibits a beta-turn like structure and is stabilized by hydrogen bonding between a different carbonyl group of the pyruvyl unit of the molecule's side chain and the NH of the Thr(6) residue. The minor isomers have a cis-amide bond between the NMe-Leu(7) and Pro(8) residues that obliges the side chain to adopt an extended disposition where hydrogen bonding to the macrocycle is absent. These results suggest that the ability of the molecule's side chain to adopt a beta-turn-like conformation may not be a prerequisite for biological activity in the didemnins and that conformations having an extended side-chain may play a role in the biological activity of aplidine.
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Affiliation(s)
- Francisco Cárdenas
- Unitat de RMN d'Alt Camp, Universitat de Barcelona, Josep Samitier 1, E-08028 Barcelona, Spain
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12
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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: 81] [Impact Index Per Article: 3.7] [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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13
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Abstract
A series of mimetic cores composed of a synthetic scaffold and amino acids have been constructed and their properties investigated in chloroform. A relative measure of H-bond strength was obtained by comparing temperature coefficients derived from variable-temperature (1)H NMR experiments. Although most templates had a strong H-bond, only a single template composed of D- and L-phenylalanines was able to form two strong H-bonds. Templates containing D- and L-leucines formed only a single H-bond. The results of these studies suggest that aromatic edge-to-face interactions provide greater stabilization energy than aliphatic-aromatic interactions in the tightly packed hydrophobic cores of proteins. Partial structures of the templates were derived by analyzing a series of two-dimensional (1)H NMR spectra and performing molecular mechanics calculations using AMBER and MMFF94 force fields.
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Affiliation(s)
- J A Turk
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA
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14
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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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15
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Cárdenas F, Thormann M, Feliz M, Caba JM, Lloyd-Williams P, Giralt E. Conformational analysis of dehydrodidemnin B (aplidine) by NMR spectroscopy and molecular mechanics/dynamics calculations. J Org Chem 2001; 66:4580-4. [PMID: 11421777 DOI: 10.1021/jo010123h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dehydrodidemnin B (DDB or aplidine), a potent antitumoral natural product currently in phase II clinical trials, exists as an approximately 1:1 mixture of two slowly interconverting conformations. These are sufficiently long-lived so as to allow their resolution by HPLC. NMR spectroscopy shows that this phenomenon is a consequence of restricted rotation about the Pyr-Pro(8) terminal amide bond of the molecule's side chain. The same technique also indicates that the overall three-dimensional structures of both the cis and trans isomers of DDB are similar despite the conformational change. Molecular dynamics simulations with different implicit and explicit solvent models show that the ensembles of three-dimensional structures produced are indeed similar for both the cis and trans isomers. These studies also show that hydrogen bonding patterns in both isomers are alike and that each one is stabilized by a hydrogen bond between the pyruvyl unit at the terminus of the molecule's side chain and the Thr(6) residue situated at the junction betwen the macrocycle and the molecule's side chain. Nevertheless, each conformational isomer forms this hydrogen bond using a different pyruvyl carbonyl group: CO(2) in the case of the cis isomer and CO(1) in the case of the trans isomer.
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Affiliation(s)
- F Cárdenas
- Departament de Química Orgánica, Universitat de Barcelona, Martí i Franquès, 1-11, E-08028 Barcelona, Spain
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Ding X, Vera MD, Liang B, Zhao Y, Leonard MS, Joullié MM. Structure--activity relationships of side-chain modified didemnins. Bioorg Med Chem Lett 2001; 11:231-4. [PMID: 11206466 DOI: 10.1016/s0960-894x(00)00638-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The synthesis and antitumor activity of a novel didemnin B analogue containing a psi[CH2NH] amide bond surrogate between N-Me-D-Leu7 and Pro8 are reported. The analogue shows activity (GI50 = 4 nM) comparable to that of didemnin B (GI50 = 13 nM) in the NCI-60 tumor cell screen. This result, along with new data from previously reported synthetic didemnin analogues, is discussed within the context of the side-chain SAR for didemnins.
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Affiliation(s)
- X Ding
- Department of Chemistry, University of Pennsylvania, Philadelphia 19104-6323, USA
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17
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Abstract
The use of norbornene units to induce the formation of beta-sheet and beta-turn type structures in peptides is discussed. The norbornene unit is readily prepared by a desymmetrization reaction and is easily incorporated into a peptide chain. Depending upon the exact nature of the norbornene unit, it is possible to form structures which resemble parallel beta-sheets, antiparallel beta-sheets or beta-turns. Similar peptide analogues incorporating a cis-2-amino-cyclopropane carboxylic acid unit can also be prepared. As an illustration of the application of this chemistry, a short, asymmetric synthesis of conformationally constrained metalloprotease inhibitors is presented.
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Affiliation(s)
- M North
- Department of Chemistry, King's College, Strand, London, UK.
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18
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Vervoort H, Fenical W, Epifanio RA. Tamandarins A and B: new cytotoxic depsipeptides from a Brazilian ascidian of the family Didemnidae. J Org Chem 2000; 65:782-92. [PMID: 10814011 DOI: 10.1021/jo991425a] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structures of two new, naturally occurring cytotoxic depsipeptides, tamandarins A and B (1 and 2), are presented. The tamandarins were isolated from an unidentified Brazilian marine ascidian of the family Didemnidae. The structures of the new cytotoxins were assigned by interpretation of FABMS data and by extensive 2D NMR analyses. The absolute configurations of the tamandarins were assigned by acid and alkaline hydrolysis to yield their corresponding amino acids, which were then analyzed as their Marfey derivatives. The cytotoxicity of tamandarin A (1) was evaluated against various human cancer cell lines and shown to be slightly more potent than didemnin B. A qualitative discussion of the conformation of tamandarin A (1) in solution, obtained from NMR J-value data, variable temperature experiments, and NOESY/ROESY data, is included.
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Affiliation(s)
- H Vervoort
- Center for Marine Biotechnology and Biomedicine, Scripps University of California-San Diego, La Jolla, 92093-0204, USA
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Celli N, Gallardo AM, Rossi C, Zucchetti M, D'Incalci M, Rotilio D. Analysis of aplidine (dehydrodidemnin B), a new marine-derived depsipeptide, in rat biological fluids by liquid chromatography-tandem mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1999; 731:335-43. [PMID: 10510788 DOI: 10.1016/s0378-4347(99)00262-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Aplidine (dehydrodidemnin B) is a new marine-derived depsipeptide with a powerful cytotoxic activity, which is under early clinical investigation in Europe and in the US. In order to investigate the pharmacokinetic properties of this novel drug, an HPLC-tandem mass spectrometry method was developed for the determination of aplidine in biological samples. Didemnin B, a hydroxy analogue, was used as internal standard. After protein precipitation with acetonitrile and extraction with chloroform, aplidine was chromatographed with a RP octadecylsilica column using a water-acetonitrile linear gradient in the presence of formic acid at the flow-rate of 500 microliters/min. The method was linear over a 5-100 ng/ml range (LOD = 0.5 ng/ml) in plasma and over a 1.25-125 ng/ml range (LOD = 0.2 ng/ml) in urine with precision and accuracy below 14.0%. The intra- and inter-day precision and accuracy were below 12.5%. The extraction procedure recoveries for aplidine and didemnin B were 69% and 68%, respectively in plasma and 91% and 87%, respectively in urine. Differences in linearity, LOQ, LOD and recoveries between plasma and urine samples seem to be matrix-dependent. The applicability of the method was tested by measuring aplidine in rat plasma and urine after intravenous treatment.
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Affiliation(s)
- N Celli
- G. Paone Environmental Health Center, Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti, Italy.
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20
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Banaigs B, Mansour EA, Bonnard I, Boulanger A, Francisco C. [Hysp2] and [Hap2]Didemnin B, two new [Hip2]-modified didemnin B from the tunicate Trididemnum cyanophorum. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(99)00524-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Pfizenmayer AJ, Ramanjulu JM, Vera MD, Ding X, Xiao D, Wei-Chuan C, Joullié MM. Synthesis and biological activities of [N-MeLeu5]- and [N-MePhe5]-didemnin B. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(98)01042-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Pfizenmayer AJ, Vera MD, Ding X, Xiao D, Chen WC, Joullié MM. Synthesis and biological activity of [Tic5] didemnin B. Bioorg Med Chem Lett 1998; 8:3653-6. [PMID: 9934489 DOI: 10.1016/s0960-894x(98)00662-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A didemnin B analog containing a Tic (1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid) as a conformationally restrained replacement for tyrosine has been synthesized and shown to have comparable potency as a protein biosynthesis inhibitor. Synthetic highlights include an oxidation of an alcohol to an acid in the presence of the sensitive Tic heterocycle and a modified Schmidt-type one-pot macrocyclization.
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Affiliation(s)
- A J Pfizenmayer
- Department of Chemistry, University of Pennsylvania, Philadelphia 19104-6323, USA
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23
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Ramanjulu JM, Ding X, Joullié MM, Li WR. Synthesis of a Reduced Ring Analog of Didemnin B. J Org Chem 1997. [DOI: 10.1021/jo9623696] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joshi M. Ramanjulu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Xiaobin Ding
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Madeleine M. Joullié
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Wen-Ren Li
- Department of Chemistry, National Central University, Chung-Li, Taiwan 32054, Republic of China
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Jou G, González I, Albericio F, Lloyd-Williams P, Giralt E. Total Synthesis of Dehydrodidemnin B. Use of Uronium and Phosphonium Salt Coupling Reagents in Peptide Synthesis in Solution. J Org Chem 1997; 62:354-366. [PMID: 11671410 DOI: 10.1021/jo961932h] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
New total syntheses of didemnin A and of dehydrodidemnin B are described. The latter didemnin has the highest antiproliferative activity of all members of this family of macrocyclic depsipeptides. It was produced on coupling the side chain Pyr-Pro-OH to didemnin A, which was itself synthesized by two novel routes. One of these was based on the elaboration of a linear heptadepsipeptide incorporating the first amino acid of the didemnin side chain, (R)-N(Me)-Leu. Deprotection of the amino and carboxyl terminii of this linear precursor followed by macrocyclization gave a protected derivative of didemnin A. The second route involved synthesis of the Boc-protected didemnin macrocycle from a linear hexadepsipeptide lacking (R)-N(Me)-Leu. Removal of the Boc group from the macrocycle followed by its coupling with Boc-(R)-N(Me)-Leu-OH then gave Boc-didemnin A. The overall yield was much higher for the second strategy (27% compared to 4% for the first synthesis), but both allowed synthetic didemnin A, identical with a natural sample, to be prepared. Extensive use was made of phosphonium and uronium salt-based coupling reagents, such as BOP, PyBrOP, PyAOP, HBTU, and HATU for the formation of both the secondary and tertiary amide bonds present in these complex depsipeptides.
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Affiliation(s)
- Gemma Jou
- Department of Organic Chemistry, University of Barcelona, E-08028 Barcelona, Spain
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Pfizenmayer AJ, Ramanjulu J, Vera MD, Ding X, Xiao D, Chen WC, Joullié MM. Synthesis and biological activities of [N-MeLeu5] didemnin B. Bioorg Med Chem Lett 1996. [DOI: 10.1016/s0960-894x(96)00506-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Sakai R, Rinehart KL, Kishore V, Kundu B, Faircloth G, Gloer JB, Carney JR, Namikoshi M, Sun F, Hughes RG, García Grávalos D, de Quesada TG, Wilson GR, Heid RM. Structure--activity relationships of the didemnins. J Med Chem 1996; 39:2819-34. [PMID: 8709112 DOI: 10.1021/jm960048g] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Bioactivities of 42 didemnin congeners, either isolated from the marine tunicates Trididemnun solidum and Aplidium albicans or prepared synthetically and semisynthetically, have been compared. The growth inhibition of various murine and human tumor cells and plaque reduction of HSV-1 and VSV grown on cultured mammalian cells were used to assess cytotoxicity and antiviral activity. Biochemical assays for macromolecular synthesis (protein, DNA, and RNA) and enzyme inhibition (dihydrofolate reductase, thymidylate synthase, DNA polymerase, RNA polymerase, and topoisomerases I and II) were also performed to specify the mechanisms of action of each analogue. Immunosuppressive activity of the didemnins was determined using a mixed lymphocyte reaction (MLR) assay. These assays revealed that the native cyclic depsipeptide core is an essential structural requirement for most of the bioactivites of the didemnins, especially for cytotoxicities and antiviral activities. The linear side-chain portion of the peptide can be altered with a gain, in some cases, of bioactivities. In particular, dehydrodidemnin B, tested against several types of tumor cells and in in vivo studies in mice, as well as didemnin M, tested for the mixed lymphocyte reaction and graft vs host reaction in murine systems, showed remarkable gains in their in vitro and in vivo activities compared to didemnin B.
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Affiliation(s)
- R Sakai
- Roger Adams Laboratory, University of Illinois, Urbana 61801, USA
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Ramanjulu JM, Joullié MM. A Facile Synthesis of Benzyl 2-Amino-3-azido-4-O-p-methoxybenzyl-6-O-benzyl-2,3-dideoxy-α-d-glucopyranoside: A Key Intermediate in the Formation Of A Didemnin B Analog. J Carbohydr Chem 1996. [DOI: 10.1080/07328309608005660] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Hossain MB, Van Der Helm D, Antel J, Sheldrick GM, Weinheimer AJ, Sanduja SK. Crystal and molecular structure of didemnin A, an antiviral depsipeptide. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1996; 47:20-7. [PMID: 8907495 DOI: 10.1111/j.1399-3011.1996.tb00805.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The molecular structure of didemnin A, the parent compound of a series of antiviral cytotoxic depsipeptides extracted from a marine tunicate Trididemnum solidum of the family of Didemnidae, has been determined by single-crystal X-ray diffraction. In the crystal, didemnin A molecules form pseudo-symmetric dimeric pair. The two molecules in the dimer are held together by strong N--H center dot center dot center dot O and N--H center dot center dot center dot N hydrogen bonds. A chloride ion, placed almost symmetrically between the dimeric pair, forms N--H center dot center dot center dot Cl hydrogen bonds (3.19 and 3.23 Angstrom) with both the molecules. The two independent molecules in the structure have closely similar geometry. For each molecule, the 23-membered depsipeptide ring assumes a folded conformation in the shape of a 'bent figure-of-eight' similar to that observed in the didemnin B crystal structure. The major conformational differences in the macrocycle of didemnin A and didemnin B are around the Hip residue. The root mean-square (RMS) difference of 20 of the 23 endocyclic torsion angles for the two structures is less than 10 degrees, while the three bond torsions in the Hip residue vary by about 50 degrees. The macrocycle conformation is stabilized by a transannular N--H center dot center dot center dot O hydrogen bond linking the isostatine amide group with the leucine carbonyl group. The truncated linear chain is folded back toward the macrocyclic ring and is held by a N--H center dot center dot center dot O hydrogen bond between the leucine amide group and Me-Leu carbonyl group. The transannular hydrogen bond in the didemnin A structure (N4--H center dot center dot center dot O3 = 2.83 Angstrom in both molecule a and molecule b) is noticeably stronger than that observed in the didemnin B structure (3.02 Angstrom). The X-ray structure of didemnin A is generally consistent with that obtained by NMR studies. Within the crystal, the molecules are packed in zig-zag chains formed by intermolecular O--H center dot center dot center dot O hydrogen bonds. The crystal structure and packing of didemnin A are quite different from that of the didemnin B structure.
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Affiliation(s)
- M B Hossain
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, USA
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Abou-Mansour E, Boulanger A, Badre A, Bonnard I, Banaigs B, Combaut G, Francisco C. Tyr5didemnin B and [D-Pro4]didemnin B; Two new natural didemnins with a modified macrocycle. Tetrahedron 1995. [DOI: 10.1016/0040-4020(95)00813-n] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Michael JP, Pattenden G. Marine Metaboliten und die Komplexierung von Metall-Ionen: Tatsachen und Hypothesen. Angew Chem Int Ed Engl 1993. [DOI: 10.1002/ange.19931050104] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Michael JP, Pattenden G. Marine Metabolites and Metal Ion Chelation: The Facts and the Fantasies. ACTA ACUST UNITED AC 1993. [DOI: 10.1002/anie.199300013] [Citation(s) in RCA: 144] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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34
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The Didemnins: Biological Properties, Chemistry and Total Synthesis. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/b978-0-444-89558-5.50033-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Hölzemann G, Pachler KG, Eberhart B, Hölzel H, Kraft M, Barnickel G. Synthesis, conformational studies, and molecular dynamics calculations of two cyclic tetrapeptides with 17- and 18-membered rings. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1991; 37:283-92. [PMID: 1894444 DOI: 10.1111/j.1399-3011.1991.tb00741.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Two cyclic tetrapeptides [Boc-cyclo(-Xxx-Pro-Asn-Lys-)OMe (Xxx = Asp or Glu)] were synthesized and investigated by NMR spectroscopy. They were designed in order to mimic the salt bridge found in physalaemin. Isomers of the urethane bond were observed in DMSO solution. The ROESY spectrum allowed the assignment of many signals of the minor isomer of both compounds. Conformational studies based on the temperature gradients of the NH chemical shifts, coupling constants, and ROEs revealed a similar conformation for the Asp analogue as proposed for physalaemin. A beta I turn with Pro and Asn in the corner positions was found for the major isomer. No hydrogen bonds were detected for the major isomer of the cyclic Glu analogue. Molecular dynamics calculations, using the NMR based initial structures, yielded sets of conformations in agreement with the experimental data. It is concluded that the salt bridge in physalaemin is best approximated by a lactam formed from the original amino acids.
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Affiliation(s)
- G Hölzemann
- Medicinal Chemistry Department, E. Merck, Darmstadt, Federal Republic of Germany
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Kessler H, Mronga S, Will M, Schmidt U. Solution Structure of [Me-L-Leu7]Didemnin B Determined by NMR Spectroscopy and Refined by MD Calculation. Helv Chim Acta 1990. [DOI: 10.1002/hlca.19900730104] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Chapter 21. Macrocyclic Immunomodulators. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1990. [DOI: 10.1016/s0065-7743(08)61597-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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