Probing the functional requirements of the l-haba side-chain of amikacin—synthesis, 16S A-site rRNA binding, and antibacterial activity
摘要:
The 1-amino group in amikacin was acylated with a variety of 2-hydroxy aminocarboxylic acids to probe the effect of acylation on ribosomal binding and antibacterial activity. The N-hydroxy urea analogue of amikacin (8a) in which the 2-S-hydroxyl-bearing carbon was replaced by an N-OH group was equally active against S. aureus and E. coli in vitro. The analogous tobramycin variant 9 was more active than amikacin. (C) 2003 Elsevier Science Ltd. All rights reserved.
Synthesis and Thermal Reactivity of Pyrrolidine- and 2-Pyrrolidinone-Fused Cyclic Enediynes
作者:Amit Basak、Basab Roy
DOI:10.1055/s-2006-950278
日期:2006.10
Various bicyclic enediynes containing pyrrolidine and pyrrolidinone moieties were synthesised. Thermal reactivity studies indicated the lowering of the onset temperature for Bergman cyclisation upon fusion of these heterocyclic systems onto the cyclicenediyne.
Compounds and methods of using said compounds singly or in combination with additional agents and compositions of said compounds for the treatment of cancer are disclosed Formula (I)
Late-Stage Diversification of Chiral N-Heterocyclic-Carbene Precatalysts for Enantioselective Homoenolate Additions
作者:Pinguan Zheng、Chenaimwoyo A. Gondo、Jeffrey W. Bode
DOI:10.1002/asia.201000617
日期:2011.2.1
A library of chiral triazolium salts has been prepared by late‐state diversification of a triazolium amine salt. By utilizing a primary amine as a functional handle, a single triazolium salt can be transformed into a variety of chiralN‐heterocyclic carbene precatalysts. This approach makes the preparation of chiralN‐heterocyclic carbenes possible by a single‐step modification of a triazolium salt
Synthesis of Chiral Bifunctional (Thio)Urea N-Heterocyclic Carbenes
作者:Jérôme Waser、Jonathan Brand、José Siles
DOI:10.1055/s-0029-1219543
日期:2010.4
The rapid and modular synthesis of the first bifunctional N-heterocyclic carbenes bearing a (thio)urea moiety as H-bond donor group was reported. Different analogues could be accessed in seven steps from cheap (S)-pyroglutamic acid in good overall yields (14-30%). The synthesized carbenes were active catalysts in the benzoin reaction.
synthetic strategy has been outlined to assemble enantiomerically pure Betti bases with unprecedented structures. This involves the Zr-mediated reduction of pyrrolidin-2-ones to cyclic imines and their subsequent reaction with phenolic derivatives.