The Total Synthesis of AB3217-A, a Novel Anti-mite Substance, via Intermolecular Etherification and Intramolecular Glycosylation
作者:Masaya Nakata、Tetsuro Tamai、Tadashi Kamio、Mitsuhiro Kinoshita、Kuniaki Tatsuta
DOI:10.1246/bcsj.67.3057
日期:1994.11
3-di-O-benzyl-5-O-trifluoromethanesulfonyl-1-thio-α-D-xylofuranoside which was prepared from 1,2 : 5,6-di-O-isopropylidene-α-D-glucofuranose, via an intermolecular etherificaiton. The resulting coupling product was subjected to de-O-tetrahydropyranylation and an intramolecular glycosylation to afford 4,12,13-tribenzyl-6-(benzyloxycarbonyl)AB3217-A (30). Final deprotection of 30 furnished AB3217-A.
AB3217-A的首次全合成已经实现。脱乙酰茴香霉素单元,(3S,4S,5R)-3-benzyloxy-1-(benzyloxycarbonyl)-5-[(1R)-1-羟基-1-(4-甲氧基苯基)甲基]-4-(2-四氢吡喃氧基)吡咯烷 (18) 是由 L-酒石酸二甲酯通过立体选择性吡咯烷环形成和苯基酮立体选择性还原作为关键步骤制备的。18的醇锂与D-呋喃木糖单元,苯基2,3-二-O-苄基-5-O-三氟甲磺酰基-1-硫代-α-D-呋喃木糖苷由1,2:5制备, 6-二-O-异亚丙基-α-D-呋喃葡萄糖,通过分子间醚化。将所得偶联产物进行脱-O-四氢吡喃化和分子内糖基化以提供4,12,13-三苄基-6-(苄氧羰基)AB3217-A (30)。30 提供的 AB3217-A 的最终脱保护。