Khodair Ahmed I, Schmidt Richard R
Fachbereich Chemie, Universität Konstanz, Fach M 725, D-78457 Konstanz, Germany.
Carbohydr Res. 2002 Nov 19;337(21-23):1967-78. doi: 10.1016/s0008-6215(02)00176-3.
A general strategy towards the synthesis of C-glycosyl compounds of N-acetylneuraminic acid (Neu5Ac) has been developed and successfully applied to the synthesis of C-methyl and C-phenyl derivatives. The key strategic elements are (i) chain extension of a D-gluconolactone derivative as C(6)-precursor with an allyl Grignard reagent as C(3)-precursor having in 2 position the C-linked aglycon moiety, (ii) stereoselective C-4/C-5 erythro-diol formation, (iii) 6-exo-trig selective heterocyclization, and (iv) installment of the 5-acetylamino and C-1 carboxylate functionalities. The efficiency and potential versatility of this approach was exemplified in the synthesis of C-methyl derivative 1 as target molecule.
已开发出一种合成N-乙酰神经氨酸（Neu5Ac）的C-糖基化合物的通用策略，并成功应用于C-甲基和C-苯基衍生物的合成。关键的策略要素包括：（i）以D-葡萄糖酸内酯衍生物作为C(6)前体，用烯丙基格氏试剂作为C(3)前体进行链延长，其中烯丙基格氏试剂在2位带有C-连接的苷元部分；（ii）立体选择性地形成C-4/C-5赤藓糖醇；（iii）6-外向-三取代选择性杂环化；（iv）引入5-乙酰氨基和C-1羧基官能团。该方法的效率和潜在通用性在作为目标分子的C-甲基衍生物1的合成中得到了体现。
