Condensation of aliphatic and aliphatic-aromatic α-diketones, and of substituted benzils with 2,3- and 3,4-diaminobenzoic acids and with 4,5-diamino-2-hydroxybenzoic acid gave 74 5- and 6-quinoxalinecarboxylic acids, with the same or different alkyls and aryls as substituents at position 2 and 3. The compounds with different substituents at positions 2 and 3 were resolved into positional isomers. Their structures were determined by means of the dipole moments. The compounds were tested for tuberculostatic activity. Some exhibited it