Henen, M.A.; Hamdi, A.; Farahat, A.A.; Massoud, M.A.M. Understanding Chemistry and Unique NMR Characters of Novel Amide and Ester Leflunomide Analogues. Magnetochemistry2017, 3, 41.
Henen, M.A.; Hamdi, A.; Farahat, A.A.; Massoud, M.A.M. Understanding Chemistry and Unique NMR Characters of Novel Amide and Ester Leflunomide Analogues. Magnetochemistry 2017, 3, 41.
A series of diverse substituted 5-methyl-isoxazole-4-carboxylic acid amides, imide and esters of the formula (I) in which the benzene ring is mono or disubstituted was prepared. Spectroscopic and conformational examination was investigated and a new insight involving steric interference and interesting downfield deviation due to additional diamagnetic anisotropic effect of the amidic carbonyl group and the methine protons in 2,6-diisopropyl-aryl derivative (2) as a conformationaly restricted analogues Leflunomide was discussed. Individual substituent electronic effects through resonance of p-substituents and most stable conformation of compound (2) are discussed.
Leflunomide derivatives, 2,6-diisopropylphenyl anilide chemical shift abnormalities, 5-methyl-4-isoxazole derivatives
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.