METHOD FOR PREPARING ARGATROBAN MONOHYDRATE

摘要

a polymorphic form of argatroban monohydrate is described. A method is described for preparing argatroban monohydrate obtained from (2 R ,4 R )-1-[N G -nitro-N 2 -(3-methyl-8-quinolinesulphonyl)-L-arginyl]-4-methyl-2-piperidine carboxylic acid by suitably treating crude argatroban. The method either comprises preparation of argatroban monohydrate in a continuous step or an intermediate step of isolating a purified argatroban.