The ‘naked sugar’ (+)-(1R,2R4R)-2-endo-cyano-7-oxabicyclo[2.2.1]hept-5-sn-2-exo-yl acetate ((+)-4) was converted (7 steps, 45% overall) with high stereoselectivity into (−)-(4R,5S,6R)-4,5,6-tris[(tert-butyl)dimethylsilyl]oxy}cyclohex-2-en-1-one ((−)-11). Reduction of (−)-1 with NaBH4- CeCl3 · 7 H2O, followed by deprotection of the silyl ether moieties gave (+)-conduritol F ((+)-1; 47%) whose characteristics
'裸糖'(+)-(1 R,2 R 4 R)-2-内-
氰基-7-氧杂双环[2.2.1]庚-5-sn-2-
乙酸乙酸外酯((+)- 4)(具有7个步骤,总产率为45%)以高立体选择性转化为(-)-(4 R,5 S,6 R)-4,5,6-tris [((叔丁基)二甲基甲
硅烷基]氧基}环己基-2-en-1-one((-)- 11)。用NaBH 4 -CeCl 3 ·7 H 2 O还原(-)- 1,然后将甲
硅烷基醚部分脱保护,得到(+)-
硬脂醇F((+)- 1; 47%)的特性与天然(+)-亮
氨酸-苏糖醇的特性相同。用D
IBAH还原(-)- 11,然后使甲
硅烷基醚部分脱保护,得到(-)-conduritol B((-)- 3 ; 51%)。