Synthesis of symmetrical bis-Schiff base-disulfide hybrids as highly effective anti-leishmanial agents.

Leishmaniasis has affected a wider part of population around the globe. Most often, the existing regiments to battle against leishmaniasis are inadequate and limited. In our ongoing efforts to develop new leishmanicidal agents, we have synthesized a series of novel and symmetrical bis-Schiff base-disulfide hybrids 1-27. Intermediate disulfide was synthesized from corresponding 2-aminothiol followed by reacting the coupled adduct with various aromatic aldehydes. All these compounds showed outstanding inhibition when compared with standard (Table 1). Out of twenty seven analogues, twenty two analogues i.e. 1-5, 7-13, 17-21, 23-27 analogues showed excellent inhibitory potential with EC50 values ranging from 0.010 ± 0.00 to 0.096 ± 0.01 µM while five compounds i.e. 6, 14-16, and 22 showed good inhibitory potential with EC50 values ranging from 0.10 ± 0.00 to 0.137 ± 0.01 µM when compared with the standard Amphotericin B. Structure-activity relationship has been established while molecular docking studies were performed to pin the binding interaction of active molecules. This study will help to develop new antileishmanial lead compounds.

Synthesis of novel derivatives of 4-methylbenzimidazole and evaluation of their biological activities.

4-Methylbenzimidazole 1-28 novel derivatives were synthesized and evaluated for their antiglycation and antioxidant activities. Compounds 1-7 and 11 showed excellent activities ranged 140-280 µM, better than standard drug rutin (294.46 ± 1.50 µM). Compound 1-28 were also evaluated for DPPH activities. Compounds 1-8 showed excellent activities, ranging 12-29 µM, better than standard drug n-propylgallate (IC50 = 30.30 ± 0.40 µM). For superoxide anion scavenging activity, compounds 1-7 showed better activity than standard n-propylgallate (IC50 = 106.34 ± 1.6 µM), ranged 82-104 µM. These compounds were found to be nontoxic to THP-1 cells.