2-[(4S,5S,8S,9S,10S,13R,14S,16R)-16-Bromo-4,8,10,14-tetramethyl-3,11-dioxo-hexadecahydro-cyclopenta[a]phenanthren-(17Z)-ylidene]-6-methyl-heptanoic acid acetoxymethyl ester 在
吡啶 、 sodium tetrahydroborate 作用下,
生成 2-[(3S,4S,5S,8S,9S,10S,11R,13R,14S,16R)-16-Bromo-11-hydroxy-4,8,10,14-tetramethyl-3-(toluene-4-sulfonyloxy)-hexadecahydro-cyclopenta[a]phenanthren-(17Z)-ylidene]-6-methyl-heptanoic acid acetoxymethyl ester