Phenyl guanidinobenzoate derivatives which have protease inhibitory

Abstract

Novel benzoyl esters of the following formula (I), and acid addition salts thereof, ##STR1## in which R.sub.1 and R.sub.2 are the same or different and represent a hydrogen atom or a lower alkoxy group, A represents a single bond, a linear or branched lower alkylene group, a lower alkenylene group, R.sub.3 and R.sub.4 are the same or different and represent a hydrogen atom or a lower alkyl group, or R.sub.3 and R.sub.4 join together to form a lower alkylene group, R.sub.5 represents a group of the formula, --X--(CO).sub.n --Y in which X represents a single bond, a linear or branched lower alkylene group or an alkenylene group, n is 0 or 1, Y represents a hydrogen atom, a cycloalkyl group, an aryl group, a hydroxyl group, a lower alkoxy group and the like are prepared by reacting para-nitrobenzoic acid or its derivative with a compound of the general formula (III) or its derivative ##STR2## to obtain a compound of the general formula (IV) ##STR3## followed by reducing the compound of the formula (IX) ##STR4## and subjecting the compound (IX) to guanidylation reaction, or by reaction para-guanidinobenzoic derivative with compound (III) or its derivative. The benzoyl esters have strong anti-trypsin activity, anti-thrombin activity and anticoagulant activity with low toxicity and are useful as a medicine for treatment of pancreatitis and disseminated intravascular coagulation (DIC).