Mesomorphic Properties of Novel Supramolecular Calix[4]arene Schiff Base Ester Derivatives: Design and Biological Investigation

Abstract

AbstractTwo homologues series of liquid crystals based on calix[4]arene core have been prepared by the condensing of Schiff base derivatives of 4‐n‐alkoxy benzaldehyde and 4‐amino benzoic acid at the lower rim of tert‐butyl calix[4]arene. They have been designed to a correlation between the molecular structure and mesomorphism with reference to ‐CH=N‐ and ‐COO‐ linkage group. All these compounds were characterized by elemental analyses and spectroscopic techniques such as FTIR, 1H‐NMR, and 13C‐NMR. Mesomorphic behaviour of novel materials were studied by polarising optical microscope (POM), differential scanning calorimetry (DSC) and X‐ray diffraction measurements to confirm the presence of mesophase. Comp.C7‐I to C18‐I (Series‐1) and C4‐II to C18‐II (Series‐2) shows smectic and nematic mesophase enantiotropically manner. Comp.C3‐I, C7‐I, C6‐II, C7‐II, C12‐II subjected to in vitro antimicrobial screening against two gram ( +ve) bacteria ( S.aureus, S.Pyogenes), two gram (‐ve) bacteria (E.coli, P.aeruginosa) and three fungal strains (C.albicans, A.Niger, A.clavatus).