Patent ID: 9260449
Filing Date: 2016-02-16
CPC Classification: C07D

Claim Text:
1. A method for preparing D-Biotin comprising following steps: (a) processing a condensation reaction for a compound of Formula B and a compound of methane tricarboxylic acid trialkyl ester in presence of dimethyl sulfoxide and an inorganic base of sodium hydride or potassium hydride in a toluene solvent, the usage of dimethyl sulfoxide is 5-10% in volume of the usage of toluene solvent, thereafter getting a compound of Formula A; wherein the chemical formula of methane tricarboxylic acid trialkyl ester is CH(COOR) wherein the X is F or Cl or Br or I, (b) converting the compound of formula A to the D-Biotin by reaction processes of hydrolysis, decarboxylation and cyclization reaction for closing loop.