The synthesis of 1, 4-dihydro-2-methyl-and 1, 4-dihydro-1, 2-dimethyl-4-oxo-nicotinic acids was accomplished following a route other than Ochiai's procedure, which yielded the isomer 1, 6-dihydro-2-methyl-6-oxo-nicotinic acid ethyl ester, and not the 4-oxo-derivative, as reported. Analytical data confirmed the identity of the two isomer oxo-nicotinic acids. UV–vis and potentiometric preliminary data showed that Al (III) does not form complexes with 1, 6- ...
