31099-31-7Relevant articles and documents
Synthetic studies on (+)-biotin, part 151: A chiral squaramide-mediated enantioselective alcoholysis approach toward the total synthesis of (+)-biotin
Chen, Xu-Xiang,Xiong, Fei,Fu, Han,Liu, Zhi-Qian,Chen, Fen-Er
, p. 488 - 491 (2011/05/14)
An efficient stereocontrolled total synthesis of (+)-biotin (1) has been achieved via the intermediacy of Roche's lactone 5 starting from cis-1,3-dibenzyl-2-imidazole-4,5-dicarboxylic acid (2). The bifunctional cinchona alkaloid-derived squaramide-promoted enantioselective alcoholysis was utilizing as a tool for the construction of two contiguous stereocenters of C-3a and C-6a in biotin molecular with excellent enantioselectivity. In addition, the 4-carboxybutyl side chain was assembled by first using C4+C1 approach via a novel tricyclic thiophanium salt intermediate.
Synthetic Studies on d-Biotin, Part 6:1 An Expeditious and Enantiocontrolled Approach to the Total Synthesis of d-Biotin via a Polymer-Supported Chiral Oxazaborolidine-Catalyzed Reduction of meso-Cyclic Imide Strategy
Chen, Fen-Er,Yuan, Jian-Li,Dai, Hui-Fang,Kuang, Yun-Yan,Chu, Yong
, p. 2155 - 2160 (2007/10/03)
An efficient and highly enantioselective synthesis of d-biotin from the known cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid (5) was accomplished in 48% overall yield. The key reactions in the sequence involve the catalytic enantioselective reduction of meso-cyclic imide 6 using polymer-supported chiral oxazoborolidine, derived from (S)-α,α -diphenylprolinol and polymer-bound sulfonyl chloride, and the installation of the C5 side chain at C4 in the thiolactone 9 via a Ni/C-catalyzed Fukuyama coupling reaction.