Process for crystallizing a 4-azasteroid 5alpha-reductase inhibitor
US5585383A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1995 |
| Grant date | Dec 17, 1996 |
| Priority date | — |
| Expiry date | May 3, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07J73/005
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
By this invention, there is provided a process for producing crystalline 4,7.beta.-dimethyl-4-aza-5.alpha.-cholestan-3-one of structural formula (I) from 4,7.beta.-dimethyl-4-aza-5.alpha.-cholestan-3-one oil. ##STR1## This crystallization process of the present invention comprises crystallization of the oil optionally containing residual solvent with vigorous but controlled agitation. Preferably, this crystallization process is carried out at select and controlled temperatures. Further, 4,7.beta.-dimethyl-4-aza-5.alpha.-cholestan-3-one has been found to exist in at least two novel polymorphic nonsolvated forms, herein referred to as Form I and Form II. Form I can be prepared pure by careful control of the crystallization process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.