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. 29, 1992
Filed:
Apr. 09, 1990
Beecham Group p.l.c., Brentford, GB;
Abstract
A process for preparing pharmaceutically active compounds of formula (A): ##STR1## wherein X is hydrogen, hydroxy, chloro, C.sub.1-6 alkoxy or phenyl C.sub.1-6 alkoxy; and R.sub.a and R.sub.b are hydrogen, or acyl or phosphate derivatives thereof, which process comprises the preparation of an intermediate of formula (I): ##STR2## wherein R.sub.1 is C.sub.1-6 alkyl, or phenyl C.sub.1-6 alkyl in which the phenyl group is optionally substituted; R.sub.2 is hydrogen, hydroxy, chlorine, C.sub.1-6 alkoxy, phenyl C.sub.1-6 alkoxy or amino; and R.sub.3 is halogen, C.sub.1-6 alkylthio, C.sub.1-6 alkylsulphonyl, azido, an amino group or a protected amino group, via the reaction of a compound of formula (II): ##STR3## wherein R.sub.2 and R.sub.3 are as defined for formula (I) with: (a) a compound of formula (III): ##STR4## wherein R.sub.4 and R.sub.5 are independently hydrogen, C.sub.1-6 alkyl, or phenyl, or R.sub.4 and R.sub.5 together are C.sub.5-7 cycloalkyl; or