Alpha-Glucosidase Inhibitory Diterpenes from <i>Euphorbia antiquorum</i> Growing in Vietnam
Cong-Luan Tran,
Thi-Bich-Ngoc Dao,
Thanh-Nha Tran,
Dinh-Tri Mai,
Thi-Minh-Dinh Tran,
Nguyen-Minh-An Tran,
Van-Son Dang,
Thi-Xuyen Vo,
Thuc-Huy Duong,
Jirapast Sichaem
Affiliations
Cong-Luan Tran
Faculty of Pharmacy and Nursery, Tay Do University, Can Tho 94000, Vietnam
Thi-Bich-Ngoc Dao
Department of Chemistry, University of Education, 280 An Duong Vuong Street, District 5, Ho Chi Minh City 72711, Vietnam
Thanh-Nha Tran
Department of Chemistry, University of Education, 280 An Duong Vuong Street, District 5, Ho Chi Minh City 72711, Vietnam
Dinh-Tri Mai
Vietnam Academy of Science and Technology, Graduate University of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Ha Noi 11355, Vietnam
Thi-Minh-Dinh Tran
Department of Biology, University of Education, 280 An Duong Vuong Street, District 5, Ho Chi Minh City 72711, Vietnam
Nguyen-Minh-An Tran
Faculty of Chemical Engineering, Industrial University of Ho Chi Minh City, Ho Chi Minh City 71420, Vietnam
Van-Son Dang
Vietnam Academy of Science and Technology, Graduate University of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Ha Noi 11355, Vietnam
Thi-Xuyen Vo
Faculty of Technology, Van Lang University, Ho Chi Minh City 71013, Vietnam
Thuc-Huy Duong
Department of Chemistry, University of Education, 280 An Duong Vuong Street, District 5, Ho Chi Minh City 72711, Vietnam
Jirapast Sichaem
Research Unit in Natural Products Chemistry and Bioactivities, Faculty of Science and Technology, Thammasat University Lampang Center, Lampang 52190, Thailand
Bioactive-guided phytochemical investigation of Euphorbia antiquorum L. growing in Vietnam led to the isolation of five ent-atisanes, one seco-ent-atisane, and one lathyrane (ingol-type). The structures were elucidated as ent-1α,3α,16β,17-tetrahydroxyatisane (1), ethyl ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylate (2), ent-atisane-3-oxo-16β,17-acetonide (3), ent-3α-acetoxy-16β,17-dihydroxyatisane (4), ent-16β,17-dihydroxyatisane-3-one (5), calliterpenone (6), and ingol 12-acetate (7). Their chemical structures were unambiguously determined by analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry, as well as by comparison with literature data. Among them, 1 is a new compound while 2 is an ethylated artifact of ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylic acid, a new compound. Isolates were evaluated for alpha-glucosidase inhibition. Compound 3 showed the most significant inhibitory activity against alpha-glucosidase with an IC50 value of 69.62 µM. Further study on mechanism underlying yeast alpha-glucosidase inhibition indicated that 3 could retard the enzyme function by noncompetitive.
