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Abstract
(-)-Lomaiviticin A (4) is a complex C2-symmetric bacterial metabolite that contains two diazofluorene functional groups. The diazofluorene consists of naphthoquinone, cyclopentadiene, and diazo substituents fused through a σ- and π-bonding network. Additionally, (-)-lomaiviticin A (4) is a potent cytotoxin, with half-maximal inhibitory potency (IC50) values in the low nanomolar range against many cancer cell lines. Because of limitations in supply, its mechanism of action had remained a "black box" since its isolation in the early 2000s. In this Account, I describe how studies directed toward the total synthesis of (-)-lomaiviticin A (4) provided a platform to elucidate the emergent properties of this metabolite and thereby connect chemical reactivity with cellular phenotype. We first developed a convergent strategy to prepare the diazofluorene (9 + 10 → 13). We then adapted this chemistry to the synthesis of lomaiviticin aglycon (21/22) and the natural monomeric diazofluorene (-)-kinamycin F (3). The key step in the lomaiviticin aglycon (21/22) synthesis involved the stereoselective oxidative coupling of two monomeric diazofluorenes (2 × 18 → 20) to establish the cojoining carbon-carbon bond of the target. As the absolute stereochemistry of the aglycon and carbohydrate residues of (-)-lomaiviticin A (4) were unknown, we developed a semisynthetic route to the metabolite that proceeds in one step and 42% yield by diazo transfer to the more abundant isolate (-)-lomaiviticin C (6). This allowed us to complete the stereochemical assignment of (-)-lomaiviticin A (4) and provided a renewable source of material. Using this material, we established that the remarkable cytotoxic effects of (-)-lomaiviticin A (4) derive from the induction of highly toxic double-strand breaks (DSBs) in DNA. At the molecular level, 1,7-nucleophilic additions to each electrophilic diazofluorene trigger homolytic decomposition pathways that produce sp2 radicals at the carbon atoms of each diazo group. These radicals abstract hydrogen atoms from the deoxyribose of DNA, a process known to initiate strand cleavage. NMR spectroscopy and molecular mechanics simulations were used to elucidate the mode of DNA binding. These studies showed that both diazofluorenes of (-)-lomaiviticin A (4) penetrate into the duplex. This mode of non-covalent binding places each diazo carbon atom in close proximity to each DNA strand. Throughout these studies, isolates containing one diazofluorene, such as (-)-lomaiviticin C (6) and (-)-kinamycin C (2), were used as controls. Consistent with our mechanistic model, these compounds do not induce DSBs in DNA and are several orders of magnitude less potent. Reactivity studies suggest that (-)-lomaiviticin A (4) is more electrophilic than simple monomeric diazofluorenes. We attribute this to through-space delocalization of the developing negative charge in the transition state for 1,7-addition. Consistent with this mechanism of action, (-)-lomaiviticin A (4) displays selective low-picomolar potencies toward DNA DSB repair-deficient cell types. The emergent properties of (-)-lomaiviticin A (4) derive from the specific arrangement of diazo, naphthoquinone, cyclopentadiene, and ketone functional groups. These functional groups work together to yield, essentially, a masked vinyl radical that can be exposed under biological conditions. Furthermore, the rotational symmetry of the metabolite, deriving from dimerization, allows it to interact with the antiparallel symmetry of DNA and affect cleavage of the duplex.
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Affiliation(s)
- Seth B. Herzon
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States. Department of Pharmacology, Yale School of Medicine, New Haven, Connecticut 06520, United States
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2
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Eiden CG, Aldrich CC. Synthesis of a 3-Amino-2,3-dihydropyrid-4-one and Related Heterocyclic Analogues as Mechanism-Based Inhibitors of BioA, a Pyridoxal Phosphate-Dependent Enzyme. J Org Chem 2017; 82:7806-7819. [PMID: 28682613 DOI: 10.1021/acs.joc.7b00847] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Amiclenomycin (ACM) is a chemically unstable antibiotic with selective activity against Mycobacterium tuberculosis (Mtb) due to mechanism-based inhibition of BioA, a pyridoxal 5'-phosphate (PLP)-dependent aminotransferase. The first-generation ACM analogue dihydro-2-pyridone 1 maintains a similar bioactivation mechanism concluding with covalent labeling of the PLP cofactor. To improve on 1, we report the synthesis of dihydro-4-pyranone 2, dihydro-4-pyridone 3, and dihydro-4-thiopyranone 13, which were rationally designed to boost the rate of enzyme inactivation by lowering the pKa of their α-protons. We employed a unified synthetic strategy for construction of the desired heterocycles featuring α-amino ynone generation followed by 6-endo-dig cyclization. However, competitive 5-exo-dig cyclization, β-elimination of the ynone, and dimerization of the resultant α-amino carbonyls all complicated the syntheses of the dihydro-4-pyranone and dihydro-4-pyridone scaffolds. These obstacles were overcome by Teoc protection of the β-amino group in the assembly of 3 and Boc-MOM protection of the α-amino group in the synthesis of 2, enabling the efficient construction of 2 and 3 in seven steps from commercially available starting materials. Dihydro-4-pyridone 3 possessed improved enzyme inhibition as measured by its kinact value against BioA.
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Affiliation(s)
- Carter G Eiden
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, 8-174 WDH, Minneapolis, Minnesota 55455, United States
| | - Courtney C Aldrich
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, 8-174 WDH, Minneapolis, Minnesota 55455, United States
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3
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Hattori K, Koike K, Okuda K, Hirayama T, Ebihara M, Takenaka M, Nagasawa H. Solution-phase synthesis and biological evaluation of triostin A and its analogues. Org Biomol Chem 2016; 14:2090-111. [PMID: 26779679 DOI: 10.1039/c5ob02505b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triostin A is a biosynthetic precursor of echinomycin which is one of the most potent hypoxia inducible factor 1 (HIF-1) inhibitors. An improved solution-phase synthesis of triostin A on a preparative scale has been achieved in 17.5% total yield in 13 steps. New analogues of triostin A with various aromatic chromophores, oxidized intra-peptide disulfide bridges and diastereoisomeric cyclic depsipeptide cores were also successfully synthesized. All analogues had a significant inhibitory effect on HIF-1 transcriptional activation in hypoxia and cytotoxicity on MCF-7 cells, with the exception of the derivatives containing a naphthalene chromophore or a thiosulfonate bridge. For the first time, triostin A, echinomycin and the thiosulfinate analogue of triostin A have been revealed to inhibit not only DNA binding of HIF-1 but also HIF-1α protein accumulation in MCF-7 cells. Furthermore, the thiosulfinate analogue and triostin A exhibited a hypoxia-selective cytotoxicity on MCF-7 cells. The improved solution-phase synthetic procedure described herein will contribute to the development of diverse bicyclic depsipeptide drug candidates with the potential to act as novel anti-cancer agents targeting hypoxic tumor microenvironments.
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Affiliation(s)
- Kozo Hattori
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
| | - Kota Koike
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
| | - Kensuke Okuda
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
| | - Tasuku Hirayama
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
| | - Masahiro Ebihara
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu, 501-1193, Japan.
| | - Mei Takenaka
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
| | - Hideko Nagasawa
- Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu, 501-1196, Japan
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4
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Abstract
The first total synthesis of marthiapeptide A is reported. Two synthetic procedures are described: the first, which was unsuccessful, attempts to close the ring at position I, and the second, which was successful, closes the ring at position II. It appears that the first route was unsuccessful because it required cyclization next to the rigid thiazole moiety, whereas the second route closed next to the more flexible thiazoline ring.
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Affiliation(s)
- Yuqi Zhang
- School of Chemistry, The University of New South Wales , Gate 2 High Street, Sydney 2052, Australia
| | - Md Amirul Islam
- School of Chemistry, The University of New South Wales , Gate 2 High Street, Sydney 2052, Australia
| | - Shelli R McAlpine
- School of Chemistry, The University of New South Wales , Gate 2 High Street, Sydney 2052, Australia
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5
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Abstract
This review highlights known disulfide-bridged peptide bicycles and the studies on their unique structural and biological features.
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Affiliation(s)
| | - Andrei K. Yudin
- Lash Miller Chemical Laboratories
- University of Toronto
- Toronto
- Canada M5S 3H6
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6
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Woo CM, Ranjan N, Arya DP, Herzon SB. Analysis of diazofluorene DNA binding and damaging activity: DNA cleavage by a synthetic monomeric diazofluorene. Angew Chem Int Ed Engl 2014; 53:9325-8. [PMID: 25044348 PMCID: PMC4206835 DOI: 10.1002/anie.201404137] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Indexed: 01/04/2023]
Abstract
The lomaiviticins and kinamycins are complex DNA damaging natural products that contain a diazofluorene functional group. Herein, we elucidate the influence of skeleton structure, ring and chain isomerization, D-ring oxidation state, and naphthoquinone substitution on DNA binding and damaging activity. We show that the electrophilicity of the diazofluorene appears to be a significant determinant of DNA damaging activity. These studies identify the monomeric diazofluorene 11 as a potent DNA cleavage agent in tissue culture. The simpler structure of 11 relative to the natural products establishes it as a useful lead for translational studies.
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Affiliation(s)
- Christina M. Woo
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107 (USA)
| | - Nihar Ranjan
- Department of Chemistry, Clemson University, Clemson, SC 29634 (USA)
| | - Dev P. Arya
- Department of Chemistry, Clemson University, Clemson, SC 29634 (USA)
| | - Seth B. Herzon
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107 (USA)
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7
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Woo CM, Ranjan N, Arya DP, Herzon SB. Analysis of Diazofluorene DNA Binding and Damaging Activity: DNA Cleavage by a Synthetic Monomeric Diazofluorene. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201404137] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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8
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Tulla-Puche J, Auriemma S, Falciani C, Albericio F. Orthogonal chemistry for the synthesis of thiocoraline-triostin hybrids. Exploring their structure-activity relationship. J Med Chem 2013; 56:5587-600. [PMID: 23746132 DOI: 10.1021/jm4006093] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The natural compounds triostin and thiocoraline are potent antitumor agents that act as DNA bisintercalators. From a pharmaceutical point of view, these compounds are highly attractive although they present a low pharmacokinetic profile, in part due to their low solubility. Synthetically, they represent a tour de force because no robust strategies have been developed to access a broad range of these bicyclic (depsi)peptides in a straightforward manner. Here we describe solid-phase strategies to synthesize new bisintercalators, such as thiocoraline-triostin hybrids, as well as analogues bearing soluble tags. Orthogonal protection schemes (up to five from: Fmoc, Boc Alloc, pNZ, o-NBS, and Troc), together with the right concourse of the coupling reagents (HOSu, HOBt, HOAt, Oxyma, EDC, DIPCDI, PyAOP, PyBOP, HATU, COMU), were crucial to establish the synthetic plan. In vitro studies and structure-activity relationships have been shown trends in the structure-activity relationship that will facilitate the design of new bisintercalators.
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Affiliation(s)
- Judit Tulla-Puche
- Institute for Research in Biomedicine Barcelona , Baldiri Reixac 10, 08028 Barcelona, Spain
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9
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Neves Filho RAW, Stark S, Westermann B, Wessjohann LA. The multicomponent approach to N-methyl peptides: total synthesis of antibacterial (-)-viridic acid and analogues. Beilstein J Org Chem 2012; 8:2085-90. [PMID: 23209543 PMCID: PMC3511043 DOI: 10.3762/bjoc.8.234] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 10/30/2012] [Indexed: 12/18/2022] Open
Abstract
Two syntheses of natural viridic acid, an unusual triply N-methylated peptide with two anthranilate units, are presented. The first one is based on peptide-coupling strategies and affords the optically active natural product in 20% overall yield over six steps. A more economical approach with only four steps leads to the similarly active racemate by utilizing a Ugi four-component reaction (Ugi-4CR) as the key transformation. A small library of viridic acid analogues is readily available to provide first SAR insight. The biological activities of the natural product and its derivatives against the Gram-negative bacterium Aliivibrio fischeri were evaluated.
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Affiliation(s)
- Ricardo A W Neves Filho
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany, Tel: +49 345 5582 1301, Address for correspondence)
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10
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Wahyudi H, Tantisantisom W, Liu X, Ramsey DM, Singh EK, McAlpine SR. Synthesis, structure-activity analysis, and biological evaluation of sanguinamide B analogues. J Org Chem 2012; 77:10596-616. [PMID: 23050835 DOI: 10.1021/jo3017499] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the first synthesis of sanguinamide B analogues. Substituting N-methylated (N-Me) amino acids, glycine (Gly), and L- or D-phenylalanine (Phe) into the backbone of sanguinamide B showed that only l- and d-Phe residues controlled the macrocycle conformation. The N-methylated and glycine analogues all had multiple conformations, whereas the L- and D-Phe derivatives only had a single conformation. Testing of all conformer analogues showed that inclusion of an L- or D-Phe was a superior design element than incorporating the N-Me moiety that is often utilized to control macrocyclic conformation. Finally, we show that there is an ideal Phe residue (in this case L-Phe) for generating compounds that have the greatest inhibitory effect on bacterial motility. Our data support the hypothesis that the macrocyclic conformation is dictated by the benzyl moiety requiring a "pseudoequatorial" position, and all other energy considerations are secondary.
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Affiliation(s)
- Hendra Wahyudi
- School of Chemistry, Gate 2 High Street, Dalton 219, University of New South Wales, Sydney, NSW 2052, Australia
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11
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Kumar Ray A, Diederichsen U. Syntheses of Triostin A Antibiotic and Nucleobase-Functionalized Analogs as New DNA Binders. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900530] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Guitot K, Carboni S, Reiser O, Piarulli U. Synthesis of (S)- and (R)-5-Oxo-piperazine-2-Carboxylic Acid and Its Application to Peptidomimetics. J Org Chem 2009; 74:8433-6. [DOI: 10.1021/jo901389q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Karine Guitot
- Dipartimento di Scienze Chimiche e Ambientali, Università degli Studi dell’Insubria, Via Valleggio, 11, 22100 Como, Italy
- Insitut fur Organische Chemie, Universität Regensburg, Universitätstrasse, 31, 93053 Regensburg, Germany
| | - Stefano Carboni
- Dipartimento di Scienze Chimiche e Ambientali, Università degli Studi dell’Insubria, Via Valleggio, 11, 22100 Como, Italy
| | - Oliver Reiser
- Insitut fur Organische Chemie, Universität Regensburg, Universitätstrasse, 31, 93053 Regensburg, Germany
| | - Umberto Piarulli
- Dipartimento di Scienze Chimiche e Ambientali, Università degli Studi dell’Insubria, Via Valleggio, 11, 22100 Como, Italy
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13
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Tulla-Puche J, Marcucci E, Fermin M, Bayó-Puxan N, Albericio F. Protection by conformationally restricted mobility: first solid-phase synthesis of triostin A. Chemistry 2008; 14:4475-8. [PMID: 18404749 DOI: 10.1002/chem.200800372] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Judit Tulla-Puche
- Institute for Research in Biomedicine, Barcelona Science Park, Barcelona, Spain.
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14
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Koketsu K, Oguri H, Watanabe K, Oikawa H. Enzymatic Macrolactonization in the Presence of DNA Leading to Triostin A Analogs. ACTA ACUST UNITED AC 2008; 15:818-28. [DOI: 10.1016/j.chembiol.2008.05.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 05/02/2008] [Accepted: 05/30/2008] [Indexed: 11/29/2022]
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15
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Samaroo D, Vinodu M, Chen X, Drain CM. meso-Tetra(pentafluorophenyl)porphyrin as an efficient platform for combinatorial synthesis and the selection of new photodynamic therapeutics using a cancer cell line. JOURNAL OF COMBINATORIAL CHEMISTRY 2007; 9:998-1011. [PMID: 17877415 PMCID: PMC2535813 DOI: 10.1021/cc070067j] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The four para fluoro groups on 5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorophenyl)-porphyrin (TPPF20) are known to react with a variety of nucleophiles, but the reaction conditions for this substitution reaction depend on the nature of the nucleophiles, e.g. primary amines versus thiols. Glycosylated derivatives of this core porphyrin have been shown to be effective photodynamic agents in the induction of necrosis or apoptosis in several cancer cell lines. The present report demonstrates that TPPF20 can be used as a core platform to efficiently generate a variety of solution-phase combinatorial libraries. The focused combinatorial libraries have substituents that are chosen from a set of motifs known to bind biopolymers such as DNA, be taken up by cancer cells, or to render the compounds amphipathic. Incubation of a breast cancer cell line with these solution-phase libraries, followed by cell lyses and extraction, affords a selection assay. Matrix-assisted laser desorption ionization (MALDI) mass spectrometry of the extracts allows identification of the molecules taken up by the cells. Cell binding assays of the winning compounds synthesized directly indicate that both glycosylation and amphipathicity are key properties since neither tetraglycosylated porphyrins nor those with four polar groups are selected to the same extent. In addition, photodynamic efficacy was evaluated.
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Affiliation(s)
- Diana Samaroo
- Department of Chemistry and Biochemistry, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, NY 10021
| | - Mikki Vinodu
- Department of Chemistry and Biochemistry, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, NY 10021
| | - Xin Chen
- Department of Chemistry and Biochemistry, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, NY 10021
| | - Charles Michael Drain
- Department of Chemistry and Biochemistry, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, NY 10021
- The Rockefeller University, 1230 York Avenue, New York, NY 10021
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16
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Dawson S, Malkinson JP, Paumier D, Searcey M. Bisintercalator natural products with potential therapeutic applications: isolation, structure determination, synthetic and biological studies. Nat Prod Rep 2007; 24:109-26. [PMID: 17268609 DOI: 10.1039/b516347c] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Echinomycin is the prototypical bisintercalator, a molecule that binds to DNA by inserting two planar chromophores between the base-pairs of duplex DNA, placing its cyclic depsipeptide backbone in the minor groove. As such, it has been the focus of an extensive number of investigations into its biological activity, nucleic acid binding and, to some extent, its structure-activity relationships. However, echinomycin is also the parent member of an extended family of natural products that interact with DNA by a similar mechanism of bisintercalation. The structural variety in these compounds leads to changes in sequence selectivity and and biological activity, particularly as anti-tumour and anti-viral agents. One of the more recently identified marine natural products that is moving close to clinical development is thiocoraline, and it therefore seems timely to review the various bisintercalator natural products.
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Affiliation(s)
- Simon Dawson
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, 29-39 Brunswick Square, London, WC1N 1AX, UK
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17
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Bayó-Puxan N, Fernández A, Tulla-Puche J, Riego E, Cuevas C, Alvarez M, Albericio F. Total Solid-Phase Synthesis of the Azathiocoraline Class of Symmetric Bicyclic Peptides. Chemistry 2006; 12:9001-9. [PMID: 16953505 DOI: 10.1002/chem.200600815] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Thiocoraline is a potent antitumor agent isolated from the marine organism Micromonospora sp. This symmetric bicyclic depsipeptide binds the minor groove of DNA. Here we report two solid-phase strategies for the syntheses of azathiocoraline and its analogues. The thioester linkage was replaced by an amide bond to improve the compound's pharmacokinetic properties. The first strategy is based on a convergent (4+4) approach, whilst the second is a stepwise synthesis, cyclizations in both approaches occurring on the solid support. These two strategies were designed to overcome problems caused by the presence of consecutive noncommercial N-methyl amino acids, to avoid epimerization during cyclization and/or fragment condensation, and to form the disulfide bridge under solid-phase conditions. The heterocyclic moiety was added in the last step of the synthesis to assist the preparation of libraries of new compounds with potential therapeutic applications.
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Affiliation(s)
- Núria Bayó-Puxan
- Barcelona Biomedical Research Institute, University of Barcelona, Barcelona Science Park (PCB), 08028 Barcelona, Spain
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18
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Abstract
[reaction: see text] Dynamic combinatorial chemistry (DCC) is a promising technique for receptor-aided selection of high-affinity ligands from equilibrating combinatorial libraries. Identification of the specific ligand(s) selected is often challenging, however, due to difficulties associated with chromatographic separation and/or mass degeneracy within the library. Herein, we describe proof-of-concept experiments demonstrating a new technique termed resin-bound DCC (RB-DCC), which provides a solution to this problem.
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Affiliation(s)
- Brian R McNaughton
- Department of Chemistry, and The Center for Future Health, University of Rochester, Rochester, New York 14642, USA
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19
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Dietrich B, Diederichsen U. Synthesis of Cyclopeptidic Analogues of Triostin A with Quinoxalines or Nucleobases as Chromophores. European J Org Chem 2005. [DOI: 10.1002/ejoc.200400548] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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20
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Kim YB, Kim YH, Park JY, Kim SK. Synthesis and biological activity of new quinoxaline antibiotics of echinomycin analogues. Bioorg Med Chem Lett 2004; 14:541-4. [PMID: 14698199 DOI: 10.1016/j.bmcl.2003.09.086] [Citation(s) in RCA: 217] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Novel quinoxaline antibiotics having the methylenedithioether bridge as an analogue of echinomycin have been synthesized by insertion of methylene moiety between -S-S- bond. The compound 1a shows remarkable cytotoxicities against human tumor various cell lines, and is active VRE (vancomycin-resistant enterococci) within MIC range 0.5-8 microg/mL. According to the eukaryotic or prokaryotic data, 1a might be a first analogue to replace echinomycin.
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Affiliation(s)
- Yun Bong Kim
- Center for Molecular Design and Synthesis, Department of Chemistry, Korea Advanced Institute of Science and Technology, 305-701, Taejon, South Korea
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21
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Lorenz KB, Diederichsen U. Solution-phase synthesis of nucleobase-substituted analogues of triostin A. J Org Chem 2004; 69:3917-27. [PMID: 15153026 DOI: 10.1021/jo0496805] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthesis of novel analogues of triostin A presenting two identical or different nucleobases instead of the original quinoxaline substituents has been developed. The DNA bisintercalator triostin A (1) with its rigid backbone provides an optimal scaffold for a parallel preorganization of the intercalating moieties. The bicyclic octadepsipeptide is built up stepwise in solution and modified with various nucleobase-substituted acetic acids at a late stage. The choice of orthogonal protecting groups allows for the synthesis of triostin analogues bearing two different substituents.
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Affiliation(s)
- Katrin B Lorenz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstrasse 2, D-37077 Goettingen, Germany
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22
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Juodaityte J, Sewald N. Synthesis of photoswitchable amino acids based on azobenzene chromophores: building blocks with potential for photoresponsive biomaterials. J Biotechnol 2004; 112:127-38. [PMID: 15288948 DOI: 10.1016/j.jbiotec.2004.03.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2003] [Revised: 03/12/2004] [Accepted: 03/19/2004] [Indexed: 11/18/2022]
Abstract
Three novel derivatives of azobenzene substituted amino acids have been synthesized. The compounds may serve as photoswitchable building blocks in the synthesis of bicyclic peptides or peptide strands interconnected with a photoisomerizable group.
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Affiliation(s)
- Jovita Juodaityte
- Organic and Bioorganic Chemistry, Department of Chemistry, University of Bielefeld, P.O. Box 100131, D-33501 Bielefeld, Germany
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Boger DL. Solution-phase synthesis of combinatorial libraries designed to modulate protein-protein or protein-DNA interactions. Bioorg Med Chem 2003; 11:1607-13. [PMID: 12659745 DOI: 10.1016/s0968-0896(03)00031-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A short personal perspective on the development of an approach to the solution-phase synthesis of combinatorial libraries for modulating cellular signaling by inhibiting, promoting, or mimicking protein-protein or protein-DNA interactions is provided.
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Affiliation(s)
- Dale L Boger
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550North Torrey Pines Road, La Jolla, CA 92037, USA.
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Abstract
Subjecting a D-Pro-L-Pro template harboring N- and C-terminal omega-alkenyl amino acids to a ring-closure metathesis reaction afforded the corresponding macrocyclic alkenes. A cis-alkene analogue crystallized with one molecule each of water and chloroform, which were retained even after heating at 100 degrees C. By using the reduced macrocyclic product as a template, the metathesis could be repeated twice on newly installed omega-alkenyl amino acids to give three-tiered macrocarbocyclic pseudopeptides as mixtures of conformers. NMR studies revealed the high conformational stability of these motifs.
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Six-Membered Ring Systems: Diazines and Benzo Derivatives. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0959-6380(01)80015-5] [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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