Synthesis, antibacterial activities and phospholipid membrane interactions of novel dialkyl 2,2’-disulfanediyldibenzoates

Abstract

A series of dialkyl 2,2'-disulfanediyldibenzoates with alkyl chain length C8 to C12 were synthesized and characterized by spectral studies. The structure of compound 3 was also confirmed by X-ray crystallography. The compounds were found to possess good antibacterial activity, especially with respect to Gram positive bacteria, and the activity was found to increase with concomitant increase in chain length. Binding studies of compound 3 with the synthetic phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) showed that the compound interacts with biological membrane mainly via hydrophobic interactions.

<strong>Synthesis and biological properties of alkyl diaryl disulfides derivatives</strong>

“…In the 13 CNMR and DEPT of the compounds 1-3, the methyl carbon appears at δ 14.1 ppm. The aromatic carbons appear at δ 120-139 ppm and the peak at δ 171 ppm corresponding to the amide carbon.…”

“…Hence increasing the alkyl chain length enhances the anti-bacterial properties to a critical point [12,13]. Therefore, in continuation of our efforts in the synthesis of biologically active organo-sulfur compounds, we herein report the synthesis of disulfanediyldibenzamides of enhanced lipophilic character by introducing long alkyl chain C8-C12 in order to deliver electrophilic sulfur species more effectively into the bacterial cell wall.…”

“…Infrared spectra were recorded on a Bruker Alpha FTIR spectrometer (400-4000cm -1 ). 1 HNMR, 13 CNMR, DEPT, 2D NMR spectra were obtained using a Bruker Spectra spin NMR spectrometer using CDCl 3 as solvent . CHNS percentage was obtained from a Eurovector EA 3000 elemental analyser.…”