文献类型：专利

英文题名：Preparing D-biotin intermediate involves carrying out esterification of L-cystine as starting material to give L-cystine methyl ester, and then treating with benzyl isocyanate in solvent to obtain N-protected L-cystine methyl ester

作者：SHI X;MENG T;QU H

机构：[1]UNIV EAST CHINA SCI & TECHNOLOGY

申请号：CN105669703-A

申请日：2016-04-11

公开日：2016-06-15

语种：英文

收录：DERWENT

摘要：NOVELTY - D-biotin intermediate preparation involves carrying out esterification of L-cystine as starting material to give L-cystine methyl ester, and then treating with benzyl isocyanate in a solvent to obtain N-protected L-cystine methyl ester. The obtained N-protected L-cystine methyl ester is heated with a catalyst in a solvent to undergo intramolecular cyclization to obtain an imidazole ring containing compound of formula (I). The obtained imidazole ring containing compound (I) is treated with triphenylphosphine as a reducing agent to give thiol compound (II). USE - Method for preparing D-biotin intermediate (claimed). ADVANTAGE - The method prepares the D-biotin intermediate in a simple, safe and cost-effective manner with high yield on industrial scale. DETAILED DESCRIPTION - D-biotin intermediate preparation involves carrying out esterification of L-cystine as starting material to give L-cystine methyl ester, and then treating with benzyl isocyanate in a solvent to obtain N-protected L-cystine methyl ester. The obtained N-protected L-cystine methyl ester is heated with a catalyst in a solvent to undergo intramolecular cyclization to obtain an imidazole ring containing compound of formula (I). The obtained imidazole ring containing compound of formula (I) is treated with triphenylphosphine as a reducing agent to give thiol compound of formula (II). The obtained thiol compound of formula (II) is treated with phosphorus oxychloride dehydrating agent and benzaldehyde in a solvent to give a crude product, which is recrystallized to give the title compound D-biotin intermediate (3S,7aR)-6-dihydro-3-phenyl-benzylimidazo (1,5-c) thiazole-5,7-(3H,6H)dione..