申请人:The United States of America as represented by the Secretary of
公开号:US04107425A1
公开(公告)日:1978-08-15
Anomerically pure 1-.alpha.- and 1-.beta.-esters of 2,3,4,6-Tetra-O-benzyl-D-glucopyranose have been prepared in high yield by controlling the stereochemistry of 1-O-acylation of appropriately protected D-glucose. 2,3,4,6-tetra-O-benzyl-D-glucopyranose is metalated with n-butyllithium in either tetrahydrofuran or anhydrous benzene and the metalated product acylated with an appropriate alkyl, alkenyl, or aryl acid chloride. Hydrogenation of the acyl glucopyranose, when derived from a saturated acid chloride, yields the appropriate 1-.alpha.- or 1-.beta.-D-glucose ester. Reaction in tetrahydrofuran produces the .alpha.-anomer while reaction in anhydrous benzene produces the .beta.-anomer.
通过控制适当保护的D-葡萄糖的1-O-酰化的立体化学,制备了2,3,4,6-四-O-苄基-D-葡萄糖吡喃醇的1-.alpha.-和1-.beta.-酯,收率高。 2,3,4,6-四-O-苄基-D-葡萄糖吡喃醇在四氢呋喃或无水苯中与正丁基锂金属化,然后与适当的烷基,烯基或芳基酸氯酰化。当来自饱和酸氯的酰基葡萄糖吡喃醇经过氢化反应时,产生适当的1-.alpha.-或1-.beta.-D-葡萄糖酯。在四氢呋喃中反应产生.alpha.-异构体,而在无水苯中反应产生.beta.-异构体。