Combined experimental and theoretical studies on the chemical and spectroscopic properties of an antimicrobial N-(Phenyl) dimethyldisulfonimide

Abstract

A disulfonimide derivative, N-(phenyl)dimethyldisulfonimide, was synthesized by two-step sulfonationof aniline with methane sulfonyl chloride. Antimicrobial activity of the molecule was investigated againstsome bacteria and fungus species by using the microdilution method. To evaluate the structure-activityrelationship, antimicrobial activity test of the two related sulfonamide derivative was also performedunder same conditions. Results showed that the title disulfonimide have remarkable antibacterial andantifungal activities compared to sulfonamides tested. The structural characterization of the moleculewas performed by using quantum chemical calculations, single crystal X-ray diffraction, IR and NMRspectroscopies. Density functional method (DFT) at B3LYP/6-311þþG(d,p) theory level was used todetermine some characteristics of the compound such as, relative energies, molecular geometry,vibrational wavenumbers, frontier molecular orbitals, atomic charges and gauge including atomic orbitals(GIAO), 1H and 13C-NMR chemical shifts. The crystal structure of the title compound is monoclinicsystem. Conformational analysis studies showed that the molecule has two stable conformers C1 and C2.According to the calculated relative energies in the gas phase C1 conformer in C1 symmetry is the moststable one. However, X-ray, IR and NMR values are more compatible with the C1 conformer in C2symmetry in solid phase.