Terpenoids from Conceveiba guianensis Aublet

Spathoside, a cerebroside and other antibacterial constituents of the stem bark of Spathodea campanulata

Spathoside, a new cerebroside was isolated from the stem bark of Spathodea campanulata, besides known compounds (n-alkanes, linear aliphatic alcohols, sitosterol and their esters, beta-sitosterol-3-O-beta-D-glucopyranoside, oleanolic acid, pomolic acid, p-hydroxybenzoic acid and phenylethanol esters). The structures of the isolated compounds were established by spectroscopic studies. The antibacterial activity of the isolated compounds against a wide range of microorganisms was examined. They inhibited significantly the growth of some gram-positive and -negative bacteria.

Phloroglucinols with antioxidant activity and xanthonolignoids from the heartwood of Hypericum geminiflorum

A new phloroglucinol, hyperielliptone HA (1/1a), a new spirophloroglucinol possessing an unprecedented skeleton, hyperielliptone HB (2/2a), and two new xanthonolignoids, hyperielliptones HC (3) and HD (4), were isolated from the heartwood of Hypericum geminiflorum. Compounds 1/1a and 2/2a were obtained as tautomeric pairs. The structures and relative configurations of these compounds were elucidated by spectroscopic methods. In biological testing, compound 2/ 2a revealed significant inhibition of oxidative DNA damage and an inhibitory effect on xanthine oxidase.

Anti-inflammatory compounds from leaves and root bark of Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg

Alchornea cordifolia is one of the most widely-used plants in traditional medicine throughout Africa, principally for inflammatory, antimicrobial and parasitic diseases. In continuation of our investigations on its anti-inflammatory activity, we fractionated the leaf and root bark extracts and isolated six compounds which exhibited significant topical anti-inflammatory activity in the mouse ear oedema model using croton oil at a dose of 90 microg/cm2. Daucosterol (2), acetyl aleuritolic acid (4), N1,N2-diisopentenyl guanidine (5) and N1,N2,N3-triisopentenyl guanidine (6) were shown to be more active than indomethacin, while beta-sitosterol (1) and di(2-ethylhexyl) phthalate (3) were less effective. This is the first report on the presence of compounds 1, 2, 3 and 4 in this plant and of the anti-inflammatory activity of 3, 5 and 6. These compounds may account, at least in part, for the use of A. cordifolia in folk medicine to treat inflammation.