Diterpenoids from Neoboutonia glabrescens (Euphorbiaceae).

Abstract

Terpenes Terpenes U 0200Diterpenoids from Neoboutonia glabrescens (Euphorbiaceae). -Glabrescin (I), neoglabrescins A (II) and B (III), and neoboutonin (IV) are isolated along with a series of known compounds from the stem bark of Neoboutonia glabrescens. The structure of the tetra-acetate of (II) is confirmed by an X-ray structure analysis. -(TCHINDA, A. T.; TSOPMO, A.; TENE, M.; KAMNAING, P.; NGNOKAM, D.; TANE, P.; AYAFOR, J. F.; CONNOLLY*, J. D.; FARRUGIA, L. J.; Phytochemistry 64 (2003) 2, 575-581; Dep. Chem., Univ. Glasgow, Glasgow G12 8QQ, UK; Eng.) -M. Bohle 02-179

Antiplasmodial compounds from the stem bark of Neoboutonia macrocalyx pax

“…Compound 2 was found to be 3,6-dihyroxy-1,7-dimethyl-9-methoxyphenanthrene ( Figure 2) by detailed NMR analysis and comparison of its 1 H NMR and 13 C NMR data and with those reported in literature (Long et al, 1997). This compound has been isolated before from N. glabrescens (Tchinda et al, 2003).…”

“…The 1 H NMR, 13 C NMR and DEPT spectra of 3 showed characteristic features of a 3-OAcetyloleuritolic acid. The structure of compound 3 was identified by detailed 1 H NMR and 13 C NMR and also by comparison with data reported in the literature as 3-O-Acetyloleuritolic acid, a known compound that has been isolated previously from Neoboutonia glabrescens and other plant species (Addae-Mensah et al, 1992;Maciel et al, 1998;Prachayasittikul et al, 2009;Tchinda et al, 2003;Woo & Kang, 1985). The molecular formula for compound 5 was determined from its positive ion mode HR-ESI-MS data of 561.3408, [M+H] + as C 32 H 48 O 8 .…”

“…1 H/ 13 C HMBC correlations between the methyl at C-13 enabled the location of OH at C-10. The location of the rest of the protons and carbons was achieved through comparison with data in literature of a related compound, neoboutomannin (Tchinda et al 2003).…”

“…Compound 1 was numbered according to the numbering system used for neoboutomannin (Tchinda et al, 2003), which reflects its putative diterpenoid biogenetic origin. Thus compound 1 is a new degraded diterpenoid closely related to the dimer; "neoboutomannin" isolated from N.…”

“…However, in 1998, Zhao et al (1998) isolated mellerin A and B and known sterols including β-sitosterol from the leaves of N. melleri. Tchinda et al (2003) reported the isolation of neoglabrescens A and B, baliosperm and montanin from the stem bark of N. glabrescens. In 2008, Neoboutomannin and manniorthoquinone among others were isolated from the stem bark of N. mannii by Tene and co-workers (Tene et al, 2008).…”