Abstract: Benzoic acid derivatives of the formula: ##STR1## wherein n is an integer of 0 to 2; R.sub.1 to R.sub.3 which may be the same or different each represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group or nitro group; R.sub.4 is a hydroxyl group or the group --NHZ (Z is hydrogen atom or a lower alkyl group), or an alkali metal salts thereof are useful as an infection control agent.These derivatives excepting compounds of the formula above wherein n is 0 or 1; any one of R.sub.1 to R.sub.3 is 5-chloro, 5-methoxy or 5-nitro and the remainder is a hydrogen atom; and R.sub.4 is a hydroxyl group; and compounds of the formula wherein n is 0 or 1; two of R.sub.1 to R.sub.3 are 3,5-dichloro or 3,5-dinitro and the remainder is a hydrogen atom; and R.sub.4 is a hydroxy group) are novel, and they were first prepared in this invention.

Abstract: An aminobenzoic acid derivative represented by the formula ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are defined hereinbelow, which has excellent activity for improving liver function and for potentiating and normalizing immunity; a process for preparing the same; and a pharmaceutical composition containing the same are disclosed.