12-[1,3]dioxolan-2-ylmethylene-7,8-dihydroxy-6,7,8-trimethyl-5,9-dioxo-decahydro-4,10-dioxa-1-aza-cyclopentacycloundecene-1-carboxylic acid 9H-fluoren-9-ylmethyl ester 在
哌啶 作用下,
以
四氢呋喃 、
二氯甲烷 为溶剂,
以96%的产率得到(3aR,6R,7S,8R,12aR)-12-[1-[1,3]Dioxolan-2-yl-meth-(E)-ylidene]-7,8-dihydroxy-6,7,8-trimethyl-octahydro-4,10-dioxa-1-aza-cyclopentacycloundecene-5,9-dione