[EN] PROCESS FOR THE PREPARATION OF CYCLOPROPYLDIKETOPIPERAZINES AND OF A KEY INTERMEDIATE OF DS-5272 [FR] PROCÉDÉ DE PRÉPARATION DE CYCLOPROPYLDICÉTOPIPÉRAZINES ET D'UN INTERMÉDIAIRE CLÉ DE DS-5272
The N-Cyclopropylimine-1-pyrroline Photorearrangement as a Synthetic Tool: Scope and Limitations
摘要:
[GRAPHICS]The scope and limitations of the photorearrangement of N-cyclopropylimines to 1-pyrrolines are presented. The influence on the reactivity of different substituents throughout the cyclopropane ring and at the iminic position of the N-cyclopropylimine structure is discussed. The observed effects are interpreted from computational studies. The principal findings relate to (1) the enhanced reactivity of 1-substituted compounds toward rearrangement, (2) the lack of reactivity of crowded cyclopropanes, and (3) the high chemoselectivity of the process.
Potent ketoamide inhibitors of HCV NS3 protease derived from quaternized P1 groups
作者:Srikanth Venkatraman、Francisco Velazquez、Wanli Wu、Melissa Blackman、Vincent Madison、F. George Njoroge
DOI:10.1016/j.bmcl.2010.02.051
日期:2010.4
Blood borne hepatitis C infections are the primary cause for liver cirrhosis and hepatocellular carcinoma. HCV NS3 protease, a pivotal enzyme in the replication cycle of HCV virus has been the primary target for development of new drug candidates. Boceprevir and telaprevir are two novel ketoamide derived inhibitors that are currently undergoing phase-III clinical trials. These inhibitors include ketoamide functionality as serine trap and have an acidic alpha-ketoamide center that undergoes epimerization under physiological conditions. Our initial attempts to arrest this epimerization by introducing quaternary amino acids at P-1 had resulted in significantly diminished activity. In this manuscript we describe alpha quaternized P-1 group that result in potent inhibitors in the enzyme assay and demonstrate cellular activity comparable to boceprevir. (C) 2010 Elsevier Ltd. All rights reserved.
PROCESS FOR THE PREPARATION OF CYCLOPROPYLDIKETOPIPERAZINES AND OF A KEY INTERMEDIATE OF DS-5272