共查询到1条相似文献,搜索用时 0 毫秒
1.
Hui‐Fang Dai Wen‐Xue Chen Lei Zhao Fei Xiong Hao Sheng Fen‐Er Chen 《Advanced Synthesis \u0026amp; Catalysis》2008,350(10):1635-1641
A practical and asymmetric process for the total synthesis of (+)‐biotin ( 1 ) has been accomplished starting from cis‐1,3‐dibenzyl‐2‐oxoimidazolidine‐4,5‐dicarboxylic acid ( 2 ). This approach features a highly enantioselective alcoholysis of meso‐cyclic anhydride 3 into (4S,5R)‐cinnamyl hemiester 4 mediated by Cinchona alkaloids. Another attractive feature of this synthesis involves the use of recyclable palladium nanoparticles‐catalyzed assembly of the 4‐carboxybutyl chain at C‐4 in (3aS,6aR)‐thiolactone 7 employing an improved Fukuyama‐type cross‐coupling reaction 相似文献