Synthesis, structure, and antimicrobial activity of heterocyclic phenylsulfonyl- and 4-aminophenylsulfonyl-carboximidamides

Abstract

Abstract: A series of novel phenylsulfonyl- and 4-aminophenylsulfonyl-carboximidamides were synthesized by condensation of sulfonamides with heterocyclic methyl carbimidates obtained from heterocyclic carbonitriles and used 'at its inception.' The molecular structure of the obtained compounds is discussed. Compounds possessing heterocyclic systems with a nitrogen atom in the α position to the functional group showed a different single-crystal structure than expected. The synthesized derivatives were evaluated for antimicrobial activities: tuberculostatic, antibacterial, and antifungal.

Keywords: Antimicrobial activity; Crystal structure; Heterocycles; Structure–activity relationship; Sulfonamidine; Synthesis.

Scheme 1

Fig. 1

Possible systems of intramolecular hydrogen bonds in target molecules

Fig. 2

Structure of N′-(4-aminophenylsulfonyl)-4-chloropicolinimidamide showing 25 % probability displacements for ellipsoids. H atoms are shown as small spheres of arbitrary radius (intramolecular N–H···O and N–H···N interactions are represented by dashed lines)

Fig. 3

The (20) hydrogen bond motif (a) and the arrangement of the molecules in the crystal structure of N′-(4-aminophenylsulfonyl)-4-chloropicolinimidamide viewed along b axis (b). Dashed lines: N–H···O and N–H···N interactions. H atoms not involved in interactions omitted