(22R)-19-(E-Cyanmethylen)-21-(ethoxycarbonyl)-3β,5-dihydroxy-14,22-epoxy-5β,14β-cholan-24-saeurenitril 在
吡啶 、
氯化亚砜 作用下,
反应 24.0h,
以76%的产率得到ethyl 2-((4S,6aS,6bS,8aR,9R,10S,11R,12aS,12bR,14aS)-11-(cyanomethyl)-6a-((E)-2-cyanovinyl)-8a-methyl-2-oxidotetradecahydro-9,12a-ethano-4,14a-methano[1,3,2]dioxathiocino[4',5':5,6]benzo[1,2-h]chromen-10-yl)acetate