SE7406223L

Compounds of formula (I) (where R is alkyl or aralkyl and X is halogen) and their salts. (I) are useful as coccidiostats for poultry and as intermediates for compounds displaying antibacterial activity (e.g. alkylation and hydrolysis give corresponding 1-alkyl-1,4-dihydro-6,7-methylenedioxy-4-oxo-quinoline-3-carboxyl- ic acids). Usual dose is about 1 g/day. The pref. phosphorus oxyhalide is PCL3. The reaction with (II) is advantageously carried out in a solvent or in excess phosphorus oxyhalide pref. at the b.pt. of the medium. Catalysts (e.g. polyphosphoric acid) are advantageously used. (I) thus obtd. may be hydrolysed to the corresponding free acid, pref. with an alkali hydroxide in aqs. or alcoholic medium.