GB893755A - New pyrazoles and process for their manufacture - Google Patents

Abstract

The invention comprises 3-phenylsulphonylamino-pyrazoles in which the phenyl radical is unsubstituted or contains one or more C1-5 alkyl or alkoxy substituents, and in which the 4- and 5-positions of the pyrazole ring optionally bear C1-5 alkyl substituents and one of the cyclic nitrogen atoms of the pyrazole ring is substituted by a phenyl radical optionally bearing C1-5 alkyl or alkoxy or halogen substituents, or by a pyridyl radical, and the salts, such as the ammonium, alkali-metal or alkaline earth metal salts or the salts with organic bases, and N-acyl derivatives of these compounds. The compounds are made by reacting the appropriate 3-amino-pyrazole with an unsubstituted or appropriately substituted benzenesulphonyl chloride and, if desired, the product is acylated or converted into a salt, or conversely, if the first-formed product is a salt or an N-acyl compound, it may be converted into the free base. Specified products include 3-benzene-sulphonamido- and 3-p-toluenesulphonamido-, 2 - phenyl - pyrazole and 3 - benzenesulphon - amido and p-toluenesulphonamido-2-pyridyl-(21)-pyrazole. 2 - Pyridyl - (21) - 3 - amino - pyrazoles used as starting materials are made by forming a 2 - pyridyl - (21) - 3 p - amino - pyrazole - 4 - carb - oxylic acid derivative such as the ethyl ester, e.g. by reacting a 2-hydrazinopyridine with ethoxymethylene-cyanacetic acid ethyl ester, hydrolysing, if necessary, and decarboxylating. Pharmaceutical preparations for the treatment of hepatic complaints contain the compounds of the invention in admixture or conjunction with a pharmaceutical carrier. The preparations suitably take the form of tablets, dragees, solutions, suspensions or emulsions for enteral or parenteral administration.