Novel crystal of benzodiazepine derivative

摘要

A type B crystal of (R)-1-Ä2,3-dihydro-1-(2'-methylphenacyl)-2-oxo-5-phenyl-1H-1,4-benzodi azepin-3-ylÜ-3-(3-tolyl)urea. It is produced by conducting recrystallization in a solvent mixture composed of 5 parts by volume of alcohol and at least 1 part by volume of water. It is so excellent in filterability and flow that it is extremely easy to filter in the mass production thereof and to handle in the production of a pharmaceutical preparation therefrom, thus being useful in the industrial production thereof.