New Cyanostyrylcopillar[5]arene Derivative: Synthesis, Photophysical Study, Chromogenic Detection of Aliphatic Amines, and Biofilm-Antibiofilm Activity.

The synthesis, characterization, and application of a new cyanostyrylcopillar[5]arene is reported. Single-crystal X-ray diffraction and other spectroscopic techniques confirm the identity of the new copillar . The X-ray diffraction study reveals that the copillar exhibits a 1D supramolecular chain in the solid state involving π···π interactions along the crystallographic -axis and 1D chains are further connected by interchain C-H···π interactions to establish 2D supramolecular layers within the crystallographic -plane. 2D supramolecular chains on further packing introduce a 3D structure with void spaces filled with hexane molecules. Through minimal deviation in the dihedral angle, the cyano-substituted ethylenic group in shows a conjugation with the phenolic -OH, favoring intramolecular bond conjugation (ITBC) and colorimetrically detects the aliphatic amines over aromatic amines in CHCN. Among the aliphatic amines, tertiary amines are differentiated from primary and secondary amines by the naked eye through color change. Both in solution and solid states, displays vapor phase detection of volatile aliphatic amines. Antibacterial activity analysis shows that while exhibits the antibiofilm action against Gram-positive pathogenic bacteria, , it promotes biofilm formation by Gram-negative pathogenic bacteria, .