Synthesis of (+)-8-methyl cercosporamide: Stereochemical correlation of natural (−)-cercosporamide with (+)-usnic acid
作者:Alan B. Cooper、James Wang、Anil K. Saksena、Viyyoor Girijavallabhan、K.Ganguly Ashit、Chan Tze-Ming、Andrew T. McPhail
DOI:10.1016/s0040-4020(01)81572-6
日期:1992.6
The absolute configuration of the antifungal antibiotic cercosporamide was established as C-9b-(−)-(S) by correlation with synthetic (+)-8-methylcercosporamide. This was accomplished via conversion of the isoxazole (6) available from (+)-usnic acid. Structure revision of the key isoxazole (6), previously assigned structure (5), is described; some of the 13C-assignments for usnic acid made by previous