Abstract: The present invention provides a method of acylating organic amines using N,N'-diacylimidazolone derivatives represented by the general formula I as follows: ##STR1## wherein R.sub.1 and R.sub.2 are the same or different, which are selected from the group consisting of methyl, ethyl, straight or substituted aliphatic chain of C.sub.3 -C.sub.19, phenyl, heterocyclic groups, alkoxy and other organic acid substituting groups; and R.sub.3 and R.sub.4 are the same or different, which are selected from the group consisting hydrogen, methyl or ethyl, phenyl, substituted phenyl and alkoxycarbonyl, or wherein R.sub.3 and R.sub.4 form a R-substituted benzene ring having the following structure together with a carbon atom where R.sub.3 and R.sub.4 are bonded to: ##STR2## (wherein R is hydrogen, carboxyl or sulfonic groups).

Abstract: Pyridone carboxylic acid compounds and pharmaceutically acceptable salts and physiologically hydrolyzable esters thereof are provided which are represented by the formula: ##STR1## wherein R.sub.1 is a lower alkyl, a halogen-substituted lower alkyl, a lower alkenyl, a cycloalkyl, or a substituted- or unsubstituted-phenyl group; R.sub.2 is a hydrogen atom, or a lower alkyl or an amino group; A is a nitrogen atom or the group C--X wherein X is a hydrogen or a halogen atom, or an alkoxy group; and Z is a group having the formula: ##STR2## wherein n is 1 or 2; R.sub.3 and R.sub.4 each represent a hydrogen atom or a lower alkyl group, with proviso that, if n is 2, one of R.sub.3 and R.sub.4 is a hydrogen atom; R.sub.5 and R.sub.6 each represent a hydrogen atom, or a hydroxy, a lower alkoxy or an amino group which is unsubstituted or substituted by a lower alkyl group, with proviso that one of R.sub.5 and R.sub.6 is a hydrogen atom; and R.sub.7 is a hydrogen atom or a lower alkyl group.