作者:Joachim Thiem、Manfred Gerken、Bernhard Schöttmer、Joachim Weigand
DOI:10.1016/0008-6215(87)80139-8
日期:1987.7
the 3- C -methyl- d - arabino - and - d - ribo -glycosides with only little stereoselectivity. The glycosylation of benzyl 4- O -benzoyl-3- O -(4- O -benzoyl-2-bromo-2,6-dideoxy-β- d -glucopyranosyl)-2-bromo-2,6-dideoxy-β- d - glucopyranoside ( 14 ), selectively unprotected at the 3′ position, with 4 gave in excellent yield and stereoselectivity (β:α 10:1) preponderantly an all β- d -inked derivative
摘要三氟甲基磺酸银促进了4-O-苯甲酰基-2-溴-2,6-二脱氧-3-O-甲酰基-α-d-吡喃葡萄糖基溴化物(4)与依苯辛基4-O-苯甲酰基-2-溴的缩合反应-2,6-二脱氧-β-d-吡喃葡萄糖苷(5)产生二糖,其在酯裂解后得到3',4'-二醇组分(13)。通过N-碘丁二酰亚胺介导的D-Mycaral单乙酸酯与(13)苄基O-(4- O-乙酰基2,6-二脱氧-2-碘3- C 3-甲基-α-d吡喃并呋喃糖基-(1)的缩合→3)-获得O -2,6-二脱氧-β-d-阿拉伯-己吡喃糖基-(1→3)-4-O-苯甲酰基-2,6-二脱氧-β-d-阿拉伯糖-己吡喃糖苷(14)具有完全的区域特异性和立体特异性[仅α-d-(1″→3′)-键],但产量适中;可以将其转化为光神霉素的EDC-三糖的异构体。 ,是苄基4- O-苯甲酰基-2的甲基支化基团,6-二脱氧-β-d-赤型-己基吡喃糖苷-3-ulose仅具有很