The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 17, 1996
Filed:
May. 03, 1995
Andrew L Forman, Scotch Plains, NJ (US);
Sean R Holihan, Dayton, NJ (US);
Guy R Humphrey, Belle Mead, NJ (US);
David M Lashen, Edison, NJ (US);
James A McCauley, Belle Mead, NJ (US);
Paul F McKenzie, Yardley, PA (US);
Ross A Miller, Fanwood, NJ (US);
Pascal H Toma, Piscataway, NJ (US);
Merck & Co., Inc., Rahway, NJ (US);
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.