Relaxant Activity of 4H-Pyran and 1,6-Dihydropyridine Derivatives on Isolated Rat Trachea

Abstract

Derivatives of 4H-pyrans and 1,6-dihydropyridines have generated considerable attention due to their interesting biological and therapeutic values. Their pharmacological activities include vasorelaxant, anticarcinogenic, antimicrobial, and antioxidant activities. Thus, the aim of the current work is to determine the relaxant effect of synthesized 4H-pyran and 1,6-dihydropyridine derivatives with potential anti-asthmatic properties on the smooth muscle airway, with a possible Ca2+-channel blockade as a mechanism of action due to their analogy with 1,4-dihidropyridines. 4H-pyrans and 1,6-dihydropyridines were achieved using multicomponent reactions by microwave and conventional heating. Also, test samples were evaluated ex vivo to determine their relaxant effect on isolated rat tracheal rings pre-contracted with carbachol. All compounds evaluated showed a significant relaxant effect on carbachol-induced contraction in tracheal rat rings. Compounds 4b, 4e, 7a, and 8d were the most potent from the entire series and were also more potent than theophylline, used as a positive control. In conclusion, in the current work some relaxant compounds of the airway smooth muscle with potential to be developed as anti-asthmatic drugs were obtained.

Keywords

• 4H-pyrans
• 1,6-dihydropyridines
• trachea-relaxant activity
• asthma
• calcium channels