QUINOLONE DERIVATIVE AND DRUG

NEW MATERIAL:The compound of formula I [R and R are H, 1-8C alkyl or 1-4C alkenyl; R is H, 1-8C alkyl, 1-8C alkyl having 1-2 OH groups, 3- 10C alkyl having 1-2 ether bonds, etc.; Z is phenyl (substituted with H, halogen, 1-8C lower alkyl, etc.), or 5- or 6-membered unsaturated heterocylic group containing N, O or S as the hetero atom] and its salt. EXAMPLE:2-(2-Chlorphenyl)-4-quinolone-8-carboxylic acid ethyl ester. USE:Pharmaceuticals. Useful as an antiallergic agent, antithrombotic agent, analgesic expectrant, remedy for asthma, etc. It can be administered orally in contrast to known similar compounds, and keeps the effective drug action for a long time. PREPARATION:The compound of formula I can be prepared by the cyclization reaction of the compound of formula II (R is lower alkyl) or its tautomer in a proper solvent by heating for 30min-10hr.