Acid metabolites from Spirostachys africana

Munkombwe, Namboole Moses; Hughes, N. A.; Duri, Zvitendo J.

doi:10.1016/s0031-9422(97)00792-9

Cited by 7 publications

(12 citation statements)

References 2 publications

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“…The latex is also used in different parts of the world as a purgative and as an emetic agent (Van Wyk and Gericke, 2000). The heartwood of the tree is used traditionally as an insect repellent (Munkombwe et al, 1997).…”

Section: Introductionmentioning

confidence: 99%

“…Earlier phytochemical studies of the latex from Spirostachys africana have showed the presence of beyerene derivatives, diosphenols, ␣ ketols, stachynones and acid metabolites (Baarschers et al, 1962;Duri et al, 1992;Munkombwe et al, 1997). However, there are no reports on the isolation and characterization of chemical compounds from the stem bark of Spirostachys africana and their bioactivity against diarrhoea causative microrganisms.…”

Section: Introductionmentioning

confidence: 99%

“…The inhibitory activity of terpenoids on bacteria (Drewes et al, 2005), viruses (Jassim and Naji, 2003;Cho, 2006) and protozoa (Ghoshal et al, 1996) was reported. Diosphenols from other plant species have been reported to have antifeedant activity (Munkombwe et al, 1997).…”

Section: Introductionmentioning

confidence: 99%

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Antibacterial activities and cytotoxicity of terpenoids isolated from Spirostachys africana

Mathabe

Hussein

Nikolova

et al. 2008

Journal of Ethnopharmacology

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Antibacterial activities and cytotoxicity of terpenoids isolated from Spirostachys africana

Mathabe

Hussein

Nikolova

et al. 2008

Journal of Ethnopharmacology

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“…The molecular formula of 2a was determined to be C 22 These spectral data was similar to those of 5a 12) except for the chemical shifts of the C-ring moiety. This evidence suggested that excoecarin V2 (2) could be a ring A 2,3-seco-16-kaurenoid.…”

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confidence: 70%

“…7) In our search for bioactive compounds from plants of the Euphorbiaceae, we isolated three new diterpenoids, excoecarins V1-V3 (1-3) and a new flavanone glycoside (7) with five known compounds, ent-atisane-16a-ol (4) [8][9][10][11] and ent-2,3-secobeyer-15-ene-2,3-dioic acid (5), 12) ent-15,18-dihydroxylabda-8(17),13E-diene (6), 13) methyl 3,4,5-trihydroxybezoate (8), 14) and 3,4,5-trimethoxyphenol 1-O-b-D-(6-galloyl)-glucopyranoside (9) 15) from the fresh stem of E. agallocha collected in Okinawa. In this paper, we describe the stereochemistry of the new diterpenoids (1-3) and flavanone glycoside (7).…”

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confidence: 99%

Three Diterpenoids (Excoecarins V1-V3) and a Flavanone Glycoside from the Fresh Stem of Excoecaria agallocha

Konishi

Yamazoe

Kanzato

et al. 2003

CHEMICAL & PHARMACEUTICAL BULLETIN

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Excoecaria agallocha LINN. (family Euphorbiaceae) is distributed on seashores and edge-mangroves throughout tropical Africa, Asia, and northwest Australia.1) The Excoecaria genus is well known to contain skin irritants, called irritant Excoecaria factors. In traditional Thai medicine, the bark and wood of the plant is used to treat flatulence. 2,3) In Sri Lanka, the smoke of the burning wood is used in the treatment of leprosy, and the root, when pounded with ginger, as an embrocation for swollen hands and feet.4) The milky latex exuded from the bark of E. agallocha may cause blindness or blistering of the skin.2,3) This latex has been used as a poison for fish by adding it to water and to poison arrowheads. The piscicidal constituent excoecariatoxin characterizing the daphnane diterpene ester and some related compounds have been obtained from the twigs, bark, and latex of Excoecaria agallocha in Japan and Thailand, respectively.2,3,5) Daphnaneand tigliane-type diterpene esters are known to be skin irritants and tumor promoters. 2,3)Previously we reported the isolation and structural elucidation of many diterpenoids from the resinous wood of this plant, 6) as well as their inhibitory effect on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-Otetradecanoylphorbol-13-acetate (TPA) in Raji cells. 7) In our search for bioactive compounds from plants of the Euphorbiaceae, we isolated three new diterpenoids, excoecarins V1-V3 (1-3) and a new flavanone glycoside (7) with five known compounds, ent-atisane-16a-ol (4) [8][9][10][11] and ent-2,3-secobeyer-15-ene-2,3-dioic acid (5), 12) ent-15,18-dihydroxylabda-8(17),13E-diene (6), 13) methyl 3,4,5-trihydroxybezoate (8), 14) and 3,4,5-trimethoxyphenol 1-O-b-D-(6-galloyl)-glucopyranoside (9) 15) from the fresh stem of E. agallocha collected in Okinawa. In this paper, we describe the stereochemistry of the new diterpenoids (1-3) and flavanone glycoside (7).Excoecarin V1 (1) Table 2). Two of the eight methylene carbons showed lower-field chemical shifts at d 65.1 and 67.3. We therefore concluded that 1 may be a beyerane-type diterpenoid with a ketal group and primary and secondary hydroxyl groups.The 1 H-and 13 C-NMR spectra of 1 were similar to those of excoecarin D (10) 16) which was assigned to be 3a,18-dihydroxy-3b,20-epoxybeyer-15-ene, except that the methine proton at C-2 was substituted by a hydroxyl group. This was confirmed by a heteronuclear multiple-bond coherence (HMBC) experiment (Fig. 1). The relative stereochemistry of 1 was assigned on the basis of the nuclear Overhauser effect (NOE) correlations. In the NOE difference NMR experiments, irradiation at d 3.61 (H 2 -20) and 3.67 (H 2 -20) enhanced the signal intensities of H-2 and H-15, respectively. NOEs were also observed between H-5 and H-18 and between H 3 -17 and H-14, H-16. (Fig. 2) These data suggested that the structure of 1 had the same relative conformation as excoecarin D (10). To determine the absolute configuration of C-2 in 1, a modified Mosher's method 17,18) was applied following...

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