Constituents from the Stem Wood of Euphorbia quinquecostata with Phorbol Dibutyrate Receptor-Binding Inhibitory Activity

Abstract

Bioassay-guided fractionation of an EtOAc extract of the stem wood of Euphorbia quinquecostata using a phorbol dibutyrate receptor-binding assay system as a monitor yielded four inhibitory isolates (1-4), inclusive of one new compound, 17-hydroxyingenol 20-hexadecanoate (1), and three previously known compounds, ingenol 20-hexadecanoate (2), ent-16 alpha,17-dihydroxyatisan-3-one (3), and ent-3 beta,16 alpha,17-trihydroxyatisane (4). Also isolated from this extract were 10 constituents inactive in this bioassay, namely, 2,2'-dihydroxy-4,6-dimethoxy-3-methylacetophenone (5), a new structure, and nine known compounds identified as ent-13S-hydroxyatis-16-ene-3, 14-dione; 2-hydroxy-4,6-dimethoxyacetophenone (xanthoxylin); 2-hydroxy-4,6-dimethoxy-3-methylacetophenone; 6-hydroxy-7-methoxycoumarin; lupeol acetate; beta-sitosterol; sitosterol beta-D-glucopyranoside; 6,7,8-trimethoxycoumarin; and 3,3',4'-tri-O-methyl-4-O-[alpha-L-rhamnopyranosyl (1"'-->6")-beta-D-glucopyranosyl]ellagic acid. The structures of compounds 1 and 5 were established by chemical and spectroscopic methods.

Structurally Novel Bioconversion Products of the Marine Natural Product Sarcophine Effectively Inhibit JB6 Cell Transformation

“…In preliminary studies, sarcyphytol A (1) and sarcophine (3) were investigated for potential to inhibit phorbol 12,13dibutyrate binding with partially purified protein kinase C, 22 antioxidant activity based on stabilization of 1,1diphenyl-2-picrylhydrazyl free radicals, 23 and inhibition of TPA-induced ornithine decarboxylase activity with cultured mouse 308 cells. In preliminary studies, sarcyphytol A (1) and sarcophine (3) were investigated for potential to inhibit phorbol 12,13dibutyrate binding with partially purified protein kinase C, 22 antioxidant activity based on stabilization of 1,1diphenyl-2-picrylhydrazyl free radicals, 23 and inhibition of TPA-induced ornithine decarboxylase activity with cultured mouse 308 cells.…”

3,7,17-Tri-O-acetyl-5-O-butanoyl-13,15-dihydroxymyrisinol

“…Some of the plants belonging to the genus Euphorbia are used in folk medicine, for instance E. kansui is considered a herbal remedy for edema, ascites and cancer in China and investigation of this plant showed two antileukemic diterpene esters with an ingenane carbon skeleton (Wu et al, 1991). The macrocyclic and polycyclic diterpenes isolated from different species of Euphorbia plants with ingenane, tigliane and daphnane skeletons have skin-irritant, tumour-promoting and antitumour activities (Shi et al, 1995;Seip & Hecker, 1983;Mbwambo et al, 1996). Some esters of myrsinol isolated from E. myrsinites showed anti-HIV-1 reverse transcriptase (RT) inhibition (O È ksu È s et al, 1995).…”

Ingenane diterpenoids from Euphorbia esula

“…for C 33 H 42 O 7 Na, 573.2828) in the HRESIMS, indicating the presence of thirteen degrees of unsaturation. The characteristic features of the 1 H and 13 C NMR spectra suggested that 1 was an ingenane diterpenoid derivative (Mbwambo et al, 1996). Further analysis of 2D NMR spectroscopic data allowed us to determine the gross structure of the diterpenoid part.…”