A New Preparation of the Disaccharide β‐<scp>D</scp>‐ManNAc<i>p</i>‐(1 → 4)‐<scp>D</scp>‐Glc from Lactose Through a Highly Stereoselective β‐<scp>D</scp>‐Gal<i>p</i>to β‐<scp>D</scp>‐ManNAc<i>p</i>Transformation
作者:Emanuele Attolino、Giorgio Catelani、Felicia D'Andrea、Maria Nicolardi
DOI:10.1081/car-200030011
日期:2004.12.29
Abstract A new method for the construction of the β‐D‐ManNAcp‐(1 → 4)‐D‐Glc framework from lactose avoiding the β‐mannosaminylation step was developed starting from 4‐O‐(2‐acetamido‐2‐deoxy‐3,4‐O‐isopropylidene‐6‐O‐trityl‐β‐D‐talopyranosyl)‐2,3:5,6‐di‐O‐isopropylidene‐aldehydo‐D‐glucose dimethyl acetal 2, obtained from 6′‐O‐trityl‐triacetonelactose dimethyl acetal, as previously reported [Barili, P
摘要从4-O-(2-乙酰氨基-2-脱氧- 3,4-O-异亚丙基-6-O-三苯甲基-β-D-talopyranosyl)-2,3:5,6-二-O-异亚丙基-醛-D-葡萄糖二甲基乙缩醛2,得自6'-O三苯甲基三丙酮半乳糖二甲基乙缩醛,如先前报道[Barili,PL; Berti,G .;卡特拉尼(G. Catelani);达安德里亚(D'Andrea)Puccioni,L.从乳糖立体合成4-O-(2-乙酰氨基-2-脱氧-β-D-talopyranosyl)-D-葡萄糖衍生物。J.碳水化合物。化学 [2000,19,79–81。]将β-D-塔洛糖胺单元上的保护基团初步修饰为3',6'-di-O-苄基衍生物6,一种新的C-4'差向异构立体选择方案,该方案采用(a)区域选择性脱水,通过与NaH-磺酰基二咪唑系统同时活化-消除反应,提供4'-deoxy-hex-3'-eno衍生物7,(b)其区域和立体