Structure-Activity Relationships of Trans-Cinnamic Acid Derivatives on Α-Glucosidase Inhibition
Main Article Content
Abstract
Trans-Cinnamic acid and its derivatives were investigated for the α-glucosidase inhibitory activity. 4-Methoxy-trans-cinnamic acid and 4-methoxy-trans-cinnamic acid ethyl ester exerted the highest potent inhibitory activity among those of trans-cinnamic acid derivatives (IC50 = 0.04 ± 0.01 mM, 0.05 ± 0.03, respectively). The presence of hydroxyl or methoxy group at 4-position on trans-cinnamic acid moiety is necessary to enhance α-glucosidase inhibitory activity. However, compounds having larger alkoxy substituent were found to have little effect on α-glucosidase inhibition ( IC50>5 mM).The mode of inhibition of 4-methoxy-trans-cinnamic acid on α-glucosidase activity was non-competitive with Ki value of 0.06 ± 0.01 mM. In contrast, 4-methoxy-trans-cinnamic acid ethyl ester was a competitive inhibitor with Ki value of 0.02 ± 0.01 mM. Furthermore, 4-methoxy-trans-cinnamic acid also inhibit sucrase and maltase, α-glucosidase enzymes derived from rat intestine, with IC50 of 10.9 ± 0.75 mM and 8.75 ±0.80 mM, respectively. These results indicated that trans-cinnamic acid derivatives should be further evaluated as a new group of potent α-glucosidase inhibitors for the treatment of various diseases, including diabetes, anti-viral infection, and AIDS.
Article Details
Upon acceptance of an article, the Pharmacological and Therapeutic Society of Thailand will have exclusive right to publish and distribute the article in all forms and media and grant rights to others. Authors have rights to use and share their own published articles.