3-Substituted pyridines of pharmaceutical interest with a carbonyl group in the 3-position have been determined by a modification of the Koenig's reaction without interferences from the 2-and 4-substituted isomers. Nicotinic acid, nicotinamide, and nikethamide in a strongly alkaline medium were reacted with chlorbutol in absolute ethanol on a steam bath for 5 minutes. The reaction mixture was cooled in ice bath and the pH was adjusted. The chromogen was developed by the use of a solution of thiobarbituric acid, barbituric acid or benzidine dihydrochloride where a stable color was formed showing a prominent absorption peaks at 535, 580, and 525 nm respectively. The relationship between absorbance and concentration is linear in the range of 0.005 - 0.05 mg per ml for nicotinic acid, and 0.01-0.1 g per ml for nicotinamide and nikethamide. The selectivity of the method within the 3-substituted members was also investigated.
Abdel-Kader, M., Taha, A., & Abdel-Fattah, S. (1979). ASSAY OF 3-SUBSTITUTED PYRIDINES THROUGH FUJIWARA REACTION. Bulletin of Pharmaceutical Sciences Assiut University, 2(1), 59-68. doi: 10.21608/bfsa.1979.104851
MLA
M. Atef Abdel-Kader; Aly M. Taha; S. Abdel-Fattah. "ASSAY OF 3-SUBSTITUTED PYRIDINES THROUGH FUJIWARA REACTION". Bulletin of Pharmaceutical Sciences Assiut University, 2, 1, 1979, 59-68. doi: 10.21608/bfsa.1979.104851
HARVARD
Abdel-Kader, M., Taha, A., Abdel-Fattah, S. (1979). 'ASSAY OF 3-SUBSTITUTED PYRIDINES THROUGH FUJIWARA REACTION', Bulletin of Pharmaceutical Sciences Assiut University, 2(1), pp. 59-68. doi: 10.21608/bfsa.1979.104851
VANCOUVER
Abdel-Kader, M., Taha, A., Abdel-Fattah, S. ASSAY OF 3-SUBSTITUTED PYRIDINES THROUGH FUJIWARA REACTION. Bulletin of Pharmaceutical Sciences Assiut University, 1979; 2(1): 59-68. doi: 10.21608/bfsa.1979.104851