Isolation of two new triterpene glycoside from the fruits of Terminalia arjuna and their in vitro and in silico studies

Two new triterpene glycoside, Arjunoglycoside VI (1) and Arjunursglycoside I (2) alone with five previously known analogues (3-7) were isolated from methanolic extract of the fruits of Terminalia arjuna. The structures were elucidated by extensive spectroscopic studies (1 D and 2 D NMR and mass). Compound 1 and 2 showed moderate activity on alpha-chymotrypsin enzyme inhibition with IC50 values 53.8 +/- 1.39 and 64.27 +/- 1.27 mu g/mL respectively. Molecular docking was performed for compound 1 and 2 with the 1CGI alpha-crystals of a-chymotrypsin enzyme protein of Bovine from protein data bank showed -7.7 and -7.6 kcal/mol binding energy, respectively. [GRAPHICS] .