ABSTRACT
The aim of the work is to improve the synthetic process of dexrabeprazole sodium,enhance quality and yield of the product,simplify synthetic steps,and offer a stable and feasible process. Starting from 2-[[[4-(3-methoxypropoxy)-3-methylpyridine-2-yl]methyl]thio]-1 H-benzimidazole,dexrabeprazole was produced by asym-metric oxidation reaction with oxidant cumene hydroperoxide in the presence of chiral catalyst tetraisopropyl titan-ate and L-(+)-tartaric acid diethyl ester. Dexrabeprazole sodium was obtained by the reaction of purified dexrabeprazole with sodium hydroxide in a total yield of 79%with an HPLC purity of ＞99. 5%. The structure of dexrabeprazole sodium was confirmed by NMR,IR,elemental analysis and LC-MS. The improved process of dexrabeprazole sodium possesses simple operations,good yield and high purity,which is feasible for industrializa-tion.
ABSTRACT
New process reported the synthesis of telavancin using decyl alcohol as the starting material.After methanesulfonylation,nucleophilic substitution with ethanolamine,Fmoc protection,and Parikh-Doering oxidation,the intermdiate N-(9-fluorenyl-9-methoxycarbonyl) decylaminoethyl acetaldehyde (5) was obtained.Vancomycin hydrochloride and intermediate 5 were then subject to reductive amination reaction,Fmoc deprotection,and Mannich reaction to give the telavancin product.The process have been deeply studied on the two key reactions of reductive amination and Mannich reaction,and the reaction conditions have been optimized.The overall yield is 46％ based on starting material vancomycin.
ABSTRACT
Objective To research and optimize the synthesis process of(7-methoxy-1-naphthyl)acetonitrile for industrial production.Methods(7-Methoxy-1-naphthyl)acetonitrile was synthesized from industrial grade 1-amino-7-naphthol,by diazotiza?tion,Sandmeyer reaction and coupled reaction.Factors such as the reaction temperature,the reaction time and the ratio of the raw ma?terial were optimized to make the reaction conditions mild.The total yield was 53.9%.Results and Conclusion The structures of in?termediate and target compounds were confirmed by MS and 1H NMR.The new method is suitable for industrial production.
ABSTRACT
Objective: To synthesize roxatidine acetate and its salt. Methods: Using orthogonal test method, reactant ratio was made. Roxatidine acetate was synthesized. Excel was used to synthesize data and make statistics chart. Result: Salt of roxatidine ac?etate was synthesized in four steps with overall yield of 28?8%. Conclusion: The process is moderate and simple and the production cost is low.