157378-76-2Relevant 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)
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 (+)-biotin, Part 11:[1] Application of Cinchona alkaloid-mediated asymmetric alcoholysis of meso-cyclic anhydride in the total synthesis of (+)-biotin
Dai, Hui-Fang,Chen, Wen-Xue,Zhao, Lei,Xiong, Fei,Sheng, Hao,Chen, Fen-Er
experimental part, p. 1635 - 1641 (2009/07/18)
A practical and asymmetric process for the totalsyn thesis 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 mesocyclic anhydride 3 into (4S,5R)-cinnamylhemiest er 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 Fukuyamatype cross-coupling reaction.