Bioactive Diterpenoids from the Stems of Euphorbia antiquorum

Abstract

A total of 18 diterpenoids, including 10 new analogues (1−10), were isolated from Euphorbia antiquorum. The structures were characterized by spectroscopic techniques, and circular dichroism data analysis was adopted to confirm the absolute configurations of 1−10. Compounds 1− 9 were classified as ent-atisane diterpenoids, and 10 was assigned as an ent-kaurane diterpenoid. The biological evaluation of nitric oxide (NO) production inhibition was conducted, and all of these isolates showed the property of inhibiting NO generation in lipopolysaccharide-induced BV-2 cells. Further research on molecular docking disclosed the affinities between the diterpenoids obtained and inducible nitric oxide synthase.

Anti-inflammatory neo-Clerodane Diterpenoids from Ajuga pantantha

“…The ECD calculations were conducted as previously reported. 25,26 Bioassay for NO Inhibitory Effects. The evaluation of NO inhibition was tested as previously reported.…”

“…The evaluation of NO inhibition was tested as previously reported. 25,26 Western Blotting Analysis. The Western blotting experiments to analyze protein expression were carried out as reported.…”

Alpha-Glucosidase Inhibitory Diterpenes from Euphorbia antiquorum Growing in Vietnam

“…From the Vietnamese plant E. antiquorum, seven alpha-glucosidase inhibitors were isolated and elucidated, including ent-1α,3α,16β,17-tetrahydroxyatisane (1), ethyl ent-3,4seco-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). To the best of our knowledge, compounds 1-6 were isolated from this species for the first time.…”

“…Euphorbia antiquorum L., a medicinal plant, has traditionally been used for various treatments, for example, the latex has been used for emetic, purgative, and diuretic treatments, and the fresh stems for treatment of skin sores, scabies, and toothache [1][2][3]. Previous chemical studies on E. antiquorum in Thailand, Vietnam, and China have reported the wealth of diterpenoids, including lathyane, ent-atisane, ent-abietane, and ent-kaurane types [3][4][5][6][7][8]. Those isolated compounds showed various biological activities including cytotoxic, antiinflammatory, anti-HIV activities, and the inhibition of nitric oxide (NO) production [9].…”

“…As a continuation of our discovery of alpha-glucosidase inhibitory metabolites from E. antiquorum [10], the further investigation on the Vietnamese plant E. antiquorum L. was performed. In this paper, the isolation and structural elucidation of seven diterpenoids, ent-1α,3α,16β,17tetrahydroxyatisane (1), ethyl ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylate (2), entatisane-3-oxo-16β,17-acetonide (3) [11], ent-3α-acetoxy-16β,17-dihydroxyatisane (4) [12], ent-16β,17-dihydroxyatisane-3-one (5) [13], calliterpenone (6) [14], and ingol 12-acetate (7) [15] (Figure 1) from the most bioactive fraction of the title plant are reported. Their structures were elucidated by spectroscopic data analysis and compared with literature data.…”