Compounds Of First Series Research Articles

Investigation of mesomorphic, photophysical and gelation behavior in aroylhydrazone based liquid crystals: Observation of mesophase crossover phenomena

Five series of substituted aroylhydrazones having two alkoxy chains at 3- and 5- positions at amide end of the molecule have been synthesized; wherein each series differ from each other in terms of number and position of alkoxy chains at imine end. The compounds of first series with the single alkoxy chain at 4-position at imine end self-assembled into columnar hexagonal mesophase. The lower homologues of the series with alkoxy chains at 3- and 5- positions at imine end showed a transition from columnar hexagonal to columnar rectangular mesophase in cooling cycle while the higher homologues exhibited columnar hexagonal mesophase. The series with alkoxy chains at 3- and 4- positions exhibited columnar rectangular mesophase. All the homologues of series with alkoxy chains at 2-, 3- and 4- positions showed a transition from columnar rectangular to columnar oblique mesophase in cooling cycle. The series with alkoxy chains at 3-, 4- and 5- positions exhibited transition in columnar hexagonal mesophase. The mesophase crossover from one columnar mesophase to the other was found to be dependent on the chain length as well as on the temperature during the self-assembly process in these molecules. The temperature dependent columnar mesophase crossover has been observed for the first time in these systems. The substitution pattern showed an influence on the photophysical properties. The number and position of alkoxy chains played a critical role in the formation of gel in these molecules. These liquid crystalline gelators have application potential in organic optoelectronic functional materials and devices.

Synthesis and PASS-assisted evaluation of coumarin–benzimidazole derivatives as potential anti-inflammatory and anthelmintic agents

Two series of novel derivatives have been designed by coupling medicinally important coumarin and benzimidazole nuclei through different linkers. These compounds have been predicted to be potent anti-inflammatory and anthelmintic by in silico studies using PASS (prediction of activity spectra for substances) software. The compounds are synthesized and evaluated for the predicted activities as well as for their in vitro antioxidant potential. Compounds of first series (4a–4f) are found good to moderate anti-inflammatory agents. Among these, compounds 4b and 4f exhibited maximum anti-inflammatory activity (45% inhibition), which is equivalent to the activity of indomethacin (48% inhibition) after 3 h (peak inflammatory response time). Compounds of second series (5a–5f) exhibit anthelmintic activity. Amongst these, compound 5f has mortality activity marginally higher than albendazole (10–11 s). Compound 5e is found to be the most potent antioxidant with remarkable EC50 value (0.08 µM/mL), which is though a little less than that of ascorbic acid (0.03 µM/mL). In addition, a comparative analysis of calculated Lipinski’s parameters reveals that all test compounds have the propensity to be orally bioavailable. Based on these findings, compounds 4b, 4f, 5e, and 5f are identified as new leads to develop potent anti-inflammatory, anthelmintic, and antioxidant compounds.