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981.
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Makaritis A Georgiadis D Dive V Yiotakis A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(9):2079-2094
The solution-phase synthesis and resolution of new phosphinopeptidic building blocks containing a triple bond was realized in high yields and optical purities (units 3 a-d). The absolute configuration of the target compounds was unambiguously established by NMR studies. A post-assembly diversification strategy of these blocks was developed through 1,3-dipolar cycloaddition of a variety of in situ prepared nitrile oxides. This strategy led to the rapid and efficient diastereoselective preparation of a novel class of isoxazole-containing phosphinic peptides (peptides 5 a-i). Solid-phase version of this strategy was efficiently achieved on multipin solid technology, by developing a new protocol for the coupling of P-unprotected dipeptidic blocks with solid supported amino acids in a quantitative and diastereoselective manner. Optimization of dipolar cycloadditions onto pin-embodied phosphinic peptides allowed the convenient preparation of this new class of pseudopeptides. The crude phosphinic peptides (9 a-k) were obtained in high yields and purity as determined by RP-HPLC. Inhibition assays of some of these peptides revealed that they behave as very potent inhibitors of MMPs, outmatching previously reported phosphinic peptides, in terms of potency (K(i) in the range of few nM). 相似文献
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Cheeseman JD Corbett AD Gleason JL Kazlauskas RJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(6):1708-1716
Current drug discovery using combinatorial chemistry involves synthesis followed by screening, but emerging methods involve receptor-assistance to combine these steps. Adding stoichiometric amounts of receptor during library synthesis alters the kinetics or thermodynamics of the synthesis in a way that identifies the best-binding library members. Three main methods have emerged thus far in receptor-assisted combinatorial chemistry: dynamic combinatorial libraries, receptor-accelerated synthesis, and a new method, pseudo-dynamic libraries. Pseudo-dynamic libraries apply both thermodynamics and kinetics to amplify library members to easily observable levels, and attain selectivity heretofore unseen in receptor-assisted systems. 相似文献
989.
Yamago S Yamada T Ito H Hara O Mino Y Yoshida J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(21):6159-6174
A new method for constructing an oligosaccharide library composed of structurally defined oligosaccharides is presented based on an iterative glycosylation of selenoglycosides. Treatment of 2-acyl-protected selenoglycosides with bromine selectively generates beta-bromoglycosides, which serve as glycosyl cation equivalents in the oligosaccharide synthesis. Thus, the coupling of the bromoglycosides with another selenoglycoside affords the corresponding glycosylated selenoglycosides, which can be directly used to next glycosylation. The iteration of this sequence allows the synthesis of a variety of oligosaccharides including an elicitor active heptasaccharide. A characteristic feature of the iterative glycosylation is that glycosyl donors and acceptors with the same anomeric reactivity can be selectively coupled by activation of the glycosyl donor prior to coupling with the glycosyl acceptor. Therefore, same selenoglycosides can be used for both the glycosyl donors and the acceptors. This feature has been exemplified by a construction of an oligosaccharide library directed to elicitor-active oligosaccharides. The library composed of stereochemically defined oligoglucosides with considerable structural diversity can be constructed starting from simple selenoglycosides. 相似文献
990.
Boger DL Desharnais J Capps K 《Angewandte Chemie (International ed. in English)》2003,42(35):4138-4176
The high-throughput synthesis and screening of compound libraries hold tremendous promise for drug discovery and powerful methods for both solid-phase and solution-phase library preparation have been introduced. The question of which approach (solution-phase versus solid-phase) is best for the preparation of chemical libraries has been replaced by which approach is most appropriate for a particular target or screen. Herein we highlight distinctions in the two approaches that might serve as useful considerations at the onset of new programs. This is followed by a more personal account of our own focus on solution-phase techniques for the preparation of libraries designed to modulate cellular signaling by targeting protein-protein or protein-DNA interactions. The screening of our libraries against a prototypical set of extracellular and intracellular targets, using a wide range of assay formats, provided the first small-molecule modulators of the protein-protein interactions studied, and a generalized approach for conducting such studies. 相似文献