作者:Josef Schachtner、Hans-Dietrich Stachel
DOI:10.1016/0957-4166(96)00427-2
日期:1996.11
removal of the protecting groups is effected by hydrogenolysis of the benzylidene acetals ent-10 and ent-11a. This reaction leads to d-ascorbic acid ent-1a or l-isoascorbic acid ent-1b, respectively. Furthermore, the four acetonides 2 were converted by ozonolysis, transesterification and finally catalytic hydrogenation to the threonic and erythronic acid ketals 9.
当用三异丁基铝处理时,l-抗坏血酸2a和d-异抗坏血酸2b的衍生物部分发生差向异构化,生成l-异抗坏血酸ent - 2b,ent -10b或d-抗坏血酸ent - 2a ,ent -11a分别。保护基的完全除去是通过对亚甲基缩醛ent -10和ent- 11a进行氢解来实现的。该反应导致d抗坏血酸ENT -1a或1-异抗坏血酸ENT分别-1b。此外,四种丙酮化物2被臭氧分解,酯交换,最后催化氢化转化为苏糖醛和赤藓酸缩酮9。