Total Syntheses of (?)-Conduritol B ((?)-1L-Cyclohex-5-ene-1,3/2,4-tetrol) and of (+)-Conduritol F((+)-1D-Cyclohex-5-ene-1,2,4/3-tetrol). Determination of the Absolute Configuration of (+)-Leucanthemito
作者:Claude Le Drian、Jean-Paul Vionnet、Pierre Vogel
DOI:10.1002/hlca.19900730118
日期:1990.1.31
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DIBAH还原(-)- 11,然后使甲硅烷基醚部分脱保护,得到(-)-conduritol B((-)- 3 ; 51%)。