Stereoselective synthesis of yohimbine alkaloids from secologanin
作者:Richard T. Brown、Simon B. Pratt
DOI:10.1039/c39800000165
日期:——
Glucolysis of methyl secoxyloganin (3) at pH 7 has afforded, via a biogenetically patterned vinylogous aldol reaction, two key substituted cyclohexenes (6) from which the acetates of β-yohimbine (10a), yohimbine (10b), and their 19,20-dehydro derivatives (9) have been synthesised in addition to dihydrogambirtannine (11) induced to undergo selectively an alternative rearrangement leading to a carbocyclic