Patent ID: 8242281

Claim:
A compound of formula (I): in which R 1 represents hydrogen, hydroxyl, chlorine, nitro, methyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy or —NH—C(O)—CH 3 , where the alkoxy radicals for their part may be substituted by hydroxyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, —O—C(O)—CH 3 or cyclopropyl, R 2 and R 3 represent hydrogen, R 4 represents hydrogen, methyl, ethyl, n-propyl or isopropyl, where the alkyl radicals for their part may be substituted by pyridyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy or mono- or disubstituted by hydroxyl, R 5 represents hydrogen, R 6 represents methyl, ethyl n-propyl, isopropyl, where the alkyl radicals for their part may be mono- or disubstituted, independently of one another, by cyclopropyl, pyridyl, furyl, thienyl, benzimidazolyl, pyrrolidinonyl, N-methylpyrrolidinonyl, N-methylpyrrolidinyl, N-ethylpyrrolidinyl, N-methylimidazolidinonyl, or cyclopropyl and R 7 represents hydrogen or a salt thereof.