GB1306839A - Pharmaceutical compositions - Google Patents

Abstract

1306839 3-Carboxy-4-hydroxy-cinnoline derivatives IMPERIAL CHEMICAL INDUSTRIES Ltd 21 Sept 1971 [16 Oct 1970 17 Aug 1971] 49282/70 and 38483/71 Heading C2C [Also in Division A5] Novel compounds of formula wherein R<SP>1</SP> stands for a hydroxy, C 1-6 alkoxy, C 3-6 alkoxyalkoxy, C 7-10 phenylalkoxy or phenoxy radical; and the benzene ring A may optionally bear one to four substituents selected from C 1-10 alkyl, C 5-7 cycloalkyl, C 1-5 alkoxy, C 7-10 phenylalkyl and phenoxy radicals and halogen atoms and phenyl radicals which themselves may optionally bear one to three substituents selected from C 1-3 alkyl and C 1-3 alkoxy radicals and nitro groups and halogen atoms; or a pharmaceutically -acceptable salt thereof excluding the 6-, 7- and 8-fluoro compounds, the 5-, 6-, 7- and 8-chloro compounds, the 6-bromo compounds, the 5,6-, 6,7-, 7,8-. 5,8- and 6,8-dichloro compounds, the 5,7- dibromo compound, the 6- and 8-methoxy compounds, the 6- and 8-methyl compounds, the 5-bromo-6-methyl- and 7-bromo-6-methylcompounds wherein R<SP>1</SP> is OH in each case, the unsubstituted compounds wherein R<SP>1</SP> is methyl or ethyl; the 6-methoxy and the 6-chloro compounds wherein R<SP>1</SP> is ethyl; and the 6-chloro compound wherein R is methyl; are prepared by cyclization of a compound of Formula V where D denotes the ring may be substituted as for A above and X is Cl or Br using a Friedel- Crafts catalyst optionally with esterifcation of the acid and/or salt formation. Intermediates of Formula V above are prepared by action of PX 5 or SOX 2 on the dicarboxylic compound obtained by hydrolysis, optionally via the half ester, of the dicarboxylic acid ester prepared by diazotization of an optionally substituted analine and reaction with diethyl malonate.