Patent ID: 7342132
Filing Date: 2008-03-11
Classification: A61K,A61P,C07B,C07C

Abstract:
1. A highly pure (R,R)-formoterol L-tartrate composition that exhibits a differential scanning calorimetry pattern substantially the same as the differential scanning calorimetry pattern shown in FIG. 8 and obtained by a process comprising crystallizing a first polymorph (C) of (R,R)-formoterol L-tartrate from aqueous isopropyl alcohol, wherein (a) 1 part by weight of said first polymorph is dissolved, by warming, in a mixture of about 2 parts by weight isopropyl alcohol and about 2.5 parts by weight water; (b) from 1.5 to 4 additional parts by weight of isopropyl alcohol are added; (c) said solution is cooled; and (d) (R,R)-formoterol L-tartrate is separated from said solution; said first polymorph having peaks at the diffraction degrees with the intensity shown below in an X-ray powder diffraction pattern: