Arch.Immunol.Ther.Exp.

Gymnema sylvestre R. Br., one of the most important medicinal plants of the Asclepiadaceae family, is a herb distributed throughout the World, predominantly in tropical countries. The plant, widely used for the treatment of diabetes and as a diuretic in Indian proprietary medicines, possesses beneficial digestive, anti-inflammatory, hypoglycemic and anti-helmentic effects. Furthermore, it is believed to be useful in the treatment of dyspepsia, constipation, jaundice, hemorrhoids, cardiopathy, asthma, bronchitis and leucoderma. A literature survey revealed that some other notable pharmacological activities of the plant such as anti-obesity, hypolipidemic, antimicrobial, free radical scavenging and anti-inflammatory properties have been proven too. This paper aims to summarize the chemical and pharmacological reports on a large group of C-4 gem-dimethylated pentacyclic triterpenoids from Gymnema sylvestre.

https://www.mdpi.com/1420-3049/18/12/14892/pdf

C-4 Gem-Dimethylated Oleanes of Gymnema sylvestre and Their Pharmacological Activities

Two new ent-kaurane diterpenes, wedelidins A (8) and B (9), together with eighteen other constituents, including the sesquiterpenoids 1 and 2, ent-kaurane diterpenes 3–7, triterpenoids 10 and 11, steroids 12–14, and flavonoids 15–17 as well as benzene derivatives 18–20, were isolated from the aerial parts of Wedelia trilobata. The structures of wedelidins A (8) and B (9) were elucidated by extensive spectroscopic analyses (including UV, IR, NMR, and MS). Furthermore, the structures of compounds 2 and 3 were confirmed by X-ray single-crystal diffraction analyses.

ent‐Kaurane Diterpenes and Further Constituents from Wedelia trilobata

This chapter deals with secondary metabolites from African medicinal plants belonging to the triterpenoids family. The chapter highlights different skeletons of triterpenoids, including steroids, triterpenes, saponins, limonoids, and quassinoids. Furthermore, the way to identify them in a crude extract based on Nuclear Magnetic Resonance (NMR) spectra is mentioned. A biosynthesis pathway of triterpenes and steroids has been proposed. In general, up to 350 new and 100 known compounds of this class isolated from African medicinal plants as well as the biological activity of some of these compounds are reported. Moreover, compounds with interesting structures are discussed.

Triterpenes and Steroids from the Medicinal Plants of Africa

Objective
To make scientific validation of the ethnomedicinal fern Drynaria quercifolia (L.) J. Smith in relation to urinary disorders.

Antibacterial efficacy of Drynaria quercifolia (L.) J. Smith (Polypodiaceae) against clinically isolated urinary tract pathogens

Two new friedelane-type triterpenes named 12α-hydroxyfriedelane-3,15-dione and 3β-hydroxyfriedelan-25-al, together with six known compounds were isolated from the stems of Drypetes paxii HUTCH. (Euphorbiaceae). Their structures were established on the basis of conventional 1 dimensional (1D) NMR methods, 2D shift-correlated NMR experiments and mass spectra. The five friedelane-type triterpene derivatives and one olean-12-ene triterpene saponin were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria, and they appeared to be modestly active.

New friedelane triterpenoids with antimicrobial activity from the stems of Drypetes paxii.

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of Drypetes laciniata

New Friedelane Triterpenoids with Antimicrobial Activity from the Stems of Drypetes paxii.

A detailed chemical investigation of the secondary metabolites from the extract of the stem bark of Garcinia ovalifolia led to the isolation of one new prenylated xanthone named banfoxanthone and five known compounds, namely friedeline, canophyllal, ovalifoloneA, 3-methoxycheffouxanthone, endodesmiadol. Prenylated xanthones isolated from Garcinia ovalifolia and others species of genus Garcinia appear to be useful as chemotaxonomic markers in Garcinia.

/pdf/banfoxanthone-a-new-prenylated-xanthone-from-the-stem-bark-2051mmp6r4.pdf

Celine Mbazoa Djama

Papers

New friedelane triterpenoids with antimicrobial activity from the stems of Drypetes paxii.

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of Drypetes laciniata

New Friedelane Triterpenoids with Antimicrobial Activity from the Stems of Drypetes paxii.

Banfoxanthone, a new prenylated xanthone from the stem bark of Garcinia ovalifolia (Guttiferaceae)