Synthesis of three quasi liquid Schiff bases between hexanal and adenine, cytosine, and l-leucine, structural interpretation, quantum mechanical studies and biological activity prediction

Hexanal, a naturally phytochemical known to inhibit phospholipase-D and facilitates extension of shelf-life of fruits, vegetables and flower during storage. We attemped to synthesise three quasi liquid Schiff bases using hexanal as the aldehyde component and other three natural biomolecules like adenine, cytosine and l-leucine as the amine counterpart and characterised them using different spectroscopic methods like FTIR, FT-NMR, UV-VIS etc. Detailed vibrational and electronic spectral explanation are reported using experimental spectra and theoretically simulated spectra. The compound was optimised using DFT-B3LYP/6-311 + G(2d,p) and electronic spectra was generated using CAM-B3LYP functional and same basis sets. Schiff base from cytosine was found to show excellent light harvesting properties (99.99%). Analysis of wave function based properties like electrostatic potential, ALIE, non-covalent interactions etc provide information about the reactivity and stability features. PASS and subsequent docking studies predicts that the first Schiff base shows DNA Lyase inhibition and the other two shows anti-eczematic properties. (C) 2021 Elsevier B.V. All rights reserved.