Intramolecular cyclization of steroidal semicarbazones to pyrazoles using Vilsmeier reagent  

作　　者：Mahboob Alam M. Mushfiq 

机构地区：[1]Department of Chemistry, Aligarh Muslim University, Aligarh 202002, India

出　　处：《Chinese Chemical Letters》2008年第2期133-136,共4页中国化学快报（英文版）

摘　　要：The preparation of hitherto unknown steroidal heterocycles containing pyrazole fused to 6,7-position of the steroidal nucleus is described. These heterocycles were prepared by the action of Vilsmeier reagent with steroidal semicarbazones in DMF. The structure of the compounds has been established on the basis of their elemental analysis and spectral data. A general mechanistic scheme for these reactions is also suggested based on current and previous results.The preparation of hitherto unknown steroidal heterocycles containing pyrazole fused to 6,7-position of the steroidal nucleus is described. These heterocycles were prepared by the action of Vilsmeier reagent with steroidal semicarbazones in DMF. The structure of the compounds has been established on the basis of their elemental analysis and spectral data. A general mechanistic scheme for these reactions is also suggested based on current and previous results.

关 键 词：Steroidal semicarbazones HETEROCYCLES Vilsmeier reagent PYRAZOLES 

分 类 号：O626[理学—有机化学]