In the present study the 2-methylpropanamide and benzamide derivatives of carboxyterfenadine, have been synthesized by nucleophilic substitution at carboxylic acid moiety (C-33) of tertiary carbon C-19 substituted with benzene ring. The proficient and high yielding series was carried out in two steps by continuous monitoring with TLC. The carboxylic group was utilized in the formation of 2-methylpropanamide and benzamide derivatives of carboxyterfenadine. The derivatives were characterized by spectroscopic techniques including mass. The starting material (2-[4-[1-hydroxy-4-[4-(hydroxydiphenylmethyl)piperidino]butyl]phenyl]-2-methylpropanoic acid) itself is H1 receptor antagonist. Hence, all these compounds A–E were biologically evaluated for antihistaminic and anticholinergic activity, using isolated guinea pig ileum tissues.
Saeed Arayne, M., Sultana, N., Shehnaz, H., Mandukhail, S. U. R., Gilani, A. H., & Haider, A. (2017). Antihistaminic and other biological activities of 2-methylpropanamide and benzamide derivatives of carboxyterfenadine. Arabian Journal of Chemistry, 10(1), 114–120. https://doi.org/10.1016/j.arabjc.2015.01.004