Synthesis and Biological Properties of Amino Acid Amide Ligand-Based Pyridinioalkanoyl Thioesters as Anti-HIV Agents
摘要:
Hyper-mutable retroviruses such as HIV can become rapidly resistant to drugs used to treat infection, Strategies for coping with drug-resistant strains of virus include combination therapies. using viral protease and reverse transcriptase inhibitors. Another approach is the development of antiviral agents that attack mutationally nonpermissive targets that have functions essential for viral replication. Thus, the highly conserved nucleocapsid protein. NCp7, was chosen as a prime target in our search for novel anti-HIV agents that can overcome the problem of viral drug resistance. Recently, we reported (J. Med. Chem. 1999 42, 67) a novel chemotype, the pyridinioalkanoyl thioesters (PATEs), based on 2-mercaptobenzamides as the thiol component and having its amide nitrogen substituted with various phenylsulfonyl moieties. These compounds were identified as relatively nontoxic anti-HIV agents in the XTT cytoprotection assay. In this study. we wish to report a separate genre of active PATEs wherein the thiol component consists of an N-2-mercaptobenzoyl-amino acid derivative. Active derivatives (EC50 < 10 muM) reported herein were confined to amino acid primary amides or methyl amides having side chains no larger than isobutyl. Amino acids terminating in free carboxyl or carboxylic acid ester groups were mostly inactive. Selected compounds were shown to be active on chronically infected CEM/SK-1, TNFalpha-induced U1. ACH-2 cells and virucidal on cell-free virus, latently infected U I cells and acutely infected primary peripheral blood mononuclear cells (PBMCs). (C) 2002 Elsevier Science Ltd. All rights reserved.
Protection of a single-cysteine redox switch from oxidative destruction: On the functional role of sulfenyl amide formation in the redox-regulated enzyme PTP1B
作者:Santhosh Sivaramakrishnan、Andrea H. Cummings、Kent S. Gates
DOI:10.1016/j.bmcl.2009.12.001
日期:2010.1
Model reactions offer a chemical mechanism by which formation of a sulfenyl amide residue at the active site of the redox-regulated protein tyrosine phosphatase PTP1B protects the cysteine redox switch in this enzyme against irreversible oxidative destruction. The results suggest that 'overoxidation' of the sulfenyl amide redox switch to the sulfinyl amide in proteins is a chemically reversible event, because the sulfinyl amide can be easily returned to the native cysteine thiol residue via reactions with cellular thiols. (C) 2009 Elsevier Ltd. All rights reserved.