Asymmetric transfer hydrogenation using amino acid derivatives; further studies and a mechanistic proposal
摘要:
A series of investigations into the use of amino acid derivatives for the asymmetric catalysis of the transfer hydrogenation of ketones are presented. Based on the results observed, a mechanistic suggestion for the origin of the ellantioselective induction is proposed. (c) 2005 Elsevier Ltd. All rights reserved.
[EN] BOUVARDIN DERIVATIVES AND THERAPEUTIC USES THEREOF<br/>[FR] DÉRIVÉS DE BOUVARDINE ET LEURS UTILISATIONS THÉRAPEUTIQUES
申请人:UNIV COLORADO REGENTS
公开号:WO2013126617A1
公开(公告)日:2013-08-29
The present invention is directed at bouvardin analogs arid related compounds for the treatment of disorders including cancer. Provided herein are bouvardin analogs and related compounds, pharmaceutical compositions and kits comprising at least one bouvardin analog or related compound, and methods for treating disorders including cancer. In some aspects the compounds inhibit translation elongation at the ribosome. The compounds are used in combination with radiation therapy or with known chemotherapeutic compositions.
selectivity of pores by incorporating functional groups inside the pore. Readily accessible octapeptides containing (aminomethyl)benzoic acid and alanine are reported here that preferentially transport cations over halides across the lipid bilayer. Ion transport is hypothesized through pores formed by stable assemblies of the peptides. The aromatic ring(s) appear to be proximal to the pore and could be
The present application relates to dipeptide-like prodrug derivatives of 2-amino-6-([2-(4-chlorophenyl)-1,3-oxazol-4-yl]methyl}sulfanyl)-4-(4-[2,3-dihydroxypropyl]oxy}phenyl)pyridine-3,5-dicarbonitrile, processes for their preparation, their use for the treatment and/or prophylaxis of diseases, and their use for the manufacture of medicaments for the treatment and/or prophylaxis of diseases, especially of cardiovascular disorders.
Bouvardin derivatives and therapeutic uses thereof
申请人:The Regents of the University of Colorado, a body corporate
公开号:US10259846B2
公开(公告)日:2019-04-16
The present invention is directed at bouvardin analogs arid related compounds for the treatment of disorders including cancer. Provided herein are bouvardin analogs and related compounds, pharmaceutical compositions and kits comprising at least one bouvardin analog or related compound, and methods for treating disorders including cancer. In some aspects the compounds inhibit translation elongation at the ribosome. The compounds are used in combination with radiation therapy or with known chemotherapeutic compositions.
N-Desmethyl Derivatives of Deoxybouvardin and RA-VII: Synthesis and Evaluation
作者:Dale L. Boger、Jiacheng Zhou
DOI:10.1021/ja00133a010
日期:1995.7
The synthesis of the complete set of seven N-desmethyl derivatives of RA-VII (8) are described. Thus, the synthesis of the four 14-membered cycloisodityrosine derivatives 21-24 and their coupling with the two tetrapeptides 32 and 33 followed by formation of the 18-membered ring with macrocyclization provided the full set of seven desmethyl derivatives 14-20 of RA-VII (8). The solution phase conformational properties of 8 and 14-20 were examined by 1D and 2D H-1 NMR to reveal the role of N-methylation on the key conformational aspects of the natural agents. In contrast to each of the simple cycloisodityrosine derivatives 21-24 which adopt a single, rigid solution conformation possessing a secondary or tertiary trans amide central to the 14-membered ring, the natural agents including 8 adopt a single predominant solution conformation (83-88%) that corresponds closely to the X-ray structure conformation which possesses an inherently disfavored cis C-30-N-29 tertiary amide central to the 14-membered cycloisodityrosine subunit. Moreover, this cis amide is the predominant conformation (85-95%) observed with N-29-desmethyl RA-VII (14) indicating that even a secondary C-30-N-29 amide adopts this inherently disfavored cis amide stereochemistry. The minor conformation of 8 observed in solution (12-17%) is shown to be derived from a minor cis C-8-N-9 tertiary amide which was not observed with its conversion to a secondary amide. Both N-9-desmethyl RA-VII (15) and N-9,N-29-desmethyl RA-VII (18) adopt exclusively a single solution conformation that corresponds to the major solution conformations of 8 and 14. This conformation contains a characteristic cis C-30-N-29 amide central to a type VI beta-turn and the cycloisodityrosine subunit, a trans C-8-N-9 amide central to a typical type II beta-turn capped with a tight Ala(4)-NH-O=C-Ala(1) hydrogen bond, and a trans C-14-N-15 N-methyl amide. In sharp contrast, removal of the N-15 methyl group within 16, 17, 19, and 20 results in the adoption of solution conformations possessing the inherently favored trans C-30-N-29 amide central to the cycloisodityrosine (14)-membered subunit. Thus, the N-15-methyl group within 8 is responsible for the agents adoption of the disfavored cis C-30-N-29 amide central to the cycloisodityrosine subunit. Importantly, preceding studies have defined the cycloisodityrosine subunit of 8 as the pharmacophore and, in a reversal of the initially assigned roles, revealed that it is the tetrapeptide housed in the 18-membered ring that induces and maintains the rigid, normally inaccessible cis C-30-N-29 amide conformation within the 14-membered cycloisodityrosine subunit. The studies detailed herein reveal that it is the N-15-methyl group that induces this conformational preference for the disfavored cis C-30-N-29 amide and that its removal results in a major conformational change with adoption of the trans C-30-N-29 amide and a loss of biological activity.Thus, the N-15-methyl group is essential for maintenance of the conformational and biological properties of 8; the N-9-methyl group is not essential, and its removal leads to exclusive population of a single biologically active conformation; and the N-29-methyl group once thought essential td the adoption of the C-30-N-29 cis amide is not essential, and its removal does not alter the conformational or biological properties of 8.