OBR TBDMSO H A, BR2=B B, BR2=n-CAHg C, BR2=C-CsHg Meo A 1.(COC)2 H oO 1.n-BuANF HO. C 2. H2, Pd/BasO4 C OH 2. NalO4 (Me2 N)2C=S H 1.HF HO2C 2. Nalo 1PTC,2氧化脱辅基 CICO2Et LiSBu-t 1.KOH 1.(COC)2 2. TBDMSCI 大片段 2. iCuEt2 3.CH2=C(OMe)M 4 . n-BUAN tBusOBR2 TBDMSO H A, BR2=B B, BR2=n-C4H9 C, BR2=c-C5H9 S O O MeO H A 1.n-Bu4NF 2.NaIO4 O O HO2C 1.PTC, 2.氧化脱辅基 1.(COCl)2 2.H2 , Pd/BaSO4 (Me2N)2C=S O O C O H B 1.HF 2.NaIO4 O O OH HO2C ClCO2Et LiSBu-t O O O OH t -BuS 1.KOH 2.TBDMSCl 3.CH2 =C(OMe)Me 4.n-Bu4NF HO t -BuS O O O O 1.(COCl)2 2.LiCuEt2 t -BuS O O O O 大片段