Ternary Inclusion System of Chair Conformation of 4,6,10,12,16,18,22,24-Octahydroxy-2,8,14,20-tetraphenyl-resorcin[4]arene: Selective Green Synthesis,Supramolecular Behavior,and Biological Activity

Calix[4]resorcinarenes form different types of structural conformations. When their methylene carbons are substituted by four phenyl groups, the molecule can adopt both chair and cone conformations depending on the reaction temperature. The solvent-free synthesis of 4,6,10,12,16,18,22,24-octahydroxy-2,8,14,20-tetraphenyl-resorcin[4]arene led to the formation of chair conformer (C_2h) rather than the cone conformer forming a ternary inclusion complex upon crystallization from wet DMSO. The solid state structure of the ternary inclusion system was determined by single-crystal X-ray diffraction and proved that the host has adopted the chair conformation. The supramolecular interactions in the crystal structure of the solvated compound were carefully investigated. Studies on antimicrobial activities showed that the compound inhibited the growth of Gram-positive bacteria.