(Z)-(4R,5R)-5-Acetylamino-2-ethoxy-4-methoxy-5-((4S,5R,4'R)-2,2,2',2'-tetramethyl-[4,4']bi[[1,3]dioxolanyl]-5-yl)-pent-2-enoic acid ethyl ester 生成 (4S,5R,6R)-5-Acetylamino-2-hydroxy-4-methoxy-6-((1R,2R)-1,2,3-trihydroxy-propyl)-tetrahydro-pyran-2-carboxylic acid ethyl ester