methyl (2R,3S,4R,7R,8Z,10S,11S,12S,13Z,16S,17R,18S,19S,20S,21Z)-3,11,17-tris-(t-butyldimethylsilyloxy)-19-(carbamoyloxy)-7-hydroxy-2,4,10,12,14,16,18,20-octamethyl-5-oxo-tetracosa-8,13,21,23-tetraenoate 在
dicyclohexylboron chloride*Et
3N 、 trihydrido-(methanolato-
O)-borate
(1-); lithium salt 作用下,
以
四氢呋喃 为溶剂,
反应 3.25h,
以72%的产率得到methyl (2R,3S,4S,5S,7R,8Z,10S,11S,12S,13Z,16S,17R,18S,19S,20S,21Z)-3,11,17-tris-(t-butyldimethylsilyloxy)-5,7-dihydroxy-19-(carbamoyloxy)-2,4,10,12,14,16,18,20-octamethyl-tetracosa-8,13,21,23-tetraenoate