ethyl (4S,5R,6R,2E)-6-[(S)-4'-(acetoxymethyl)-3'-benzyl-2'-oxooxazolidin-4'-yl]-5-(benzyloxy)-4,6-dihydroxyhex-2-enoate 、
2,2-二甲氧基丙烷 在
D(+)-10-樟脑磺酸 作用下,
反应 3.0h,
以81%的产率得到ethyl (4S,5R,6R,2E)-6-[(S)-4'-(acetoxymethyl)-3'-benzyl-2'-oxooxazolidin-4'-yl]-5-(benzyloxy)-4,6-(isopropylidenedioxy)hex-2-enoate