RT Journal Article SR Electronic T1 The Electronic Structures and Pharmacological Activities of Sulfanilamide Derivatives and Carbonic Anhydrase Inhibitors with the Same Sulfonamide Moiety JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 446 OP 454 VO 5 IS 5 A1 TEIJIRO YONEZAWA A1 IKUKO MURO A1 HIROSHI KATO A1 MASAYASU KIMURA YR 1969 UL http://molpharm.aspetjournals.org/content/5/5/446.abstract AB The electronic structures of a series of sulfanilamide and sulfonamide derivatives have been calculated by the Hückel method and also by the extended Huckel method. In the case of the sulfanilamide derivatives (sulfa drugs), the electrophilic reactivity indices (superdelocalizability or partial atomic population) at the N4 atom in the molecule are correlated with their relative bacteriostatic activities against Escherichia coli. From the results calculated for a dihydropteridine derivative, a possible reaction mechanism is proposed in which the carbonium cation of the compound will attack the N4 atom of the sulfanilamide derivatives electrophilically. In the case of sulfonamide derivatives (carbonic anhydrase inhibitors), the relative activities as carbonic anhydrase inhibitors are discussed in terms of the electrophilic reactivity indices at the nitrogen atom of the free amino group. A hypothetical reaction model for the interpretation of the inhibitory action for carbonic anhydrase is proposed.