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Phytochemical investigation of the methanol extracts of the twigs of Manniophyton fulvum has led to the isolation and characterization of three new pentacyclic triterpenoids, designated as 3α,28-dihydroxyfriedelan-1-one (1), manniotaraxerol A (3) and manniotaraxerol B (4), along with fourteen known compounds, 3α-hydroxy-1-oxofriedelane (2), betulinic acid (5), friedelin (S1), taraxerol (S2), a mixture of stigmasterol (S3) and β-sitosterol (S4), herranone (S5), docosanoic acid (S6), ursolic acid (S7), nasutin B (S8), bergenin (S9), stigmasterol-3-O-β- d- glucopyranoside (S10), 1,2-di-O-palmitoyl-3-O-(6-sulfo-α- d -quinovopyranosyl)glycerol (S11), and aridanin (S12). The structures of all compounds were determined by comprehensive spectroscopic analyses (1D and 2D NMR, EI and ESI-MS). 3α,28-Dihydroxyfriedelan-1-one (1), 3α-hydroxy-1-oxofriedelane (2), manniotaraxerol A (3), manniotaraxerol B (4), and betulinic acid (5) were evaluated against HeLa (human cervix adenocarcinoma) cancer cells. Manniotaraxerol A (3) showed weak in vitro cytotoxicity with a cell viability value of 49.3%. Betulinic acid (5) also showed significant cytotoxicity against HeLa cell with a cell viability value of 4.0%; the other compounds were inactive in this test.

Phytochemical investigation of the stem bark of Diospyros longiflora yielded longiflorol (1), a new bergenin α-d-apioside, together with bergenin (2) and five known compounds: lupeol (S1), betulin (S2), betulinic acid (S3), stigmasterol (S4) and stigmasterol glucoside (S5). Their structures were determined by one-dimensional (1D) and 2D nuclear magnetic resonance experiments along with electrospray ionization high-resolution mass spectrometry and extended density-functional theory calculations of chiroptical properties. Longiflorol (1) and bergenin (2) were evaluated for their DPPH (2,2-diphenyl-1-picrylhydrazyl) antioxidant activity, with the crude extract for comparison and ascorbic acid as standard. The results showed that the extract and 2 had good antioxidant activity, whereas 1 showed only moderate activity at high concentration (>2 mg mL−1).

A new dimeric ent-kaurane diterpene, mannic acid (1), and 19 known compounds were isolated from the methanol extract of the stems, roots and leaves of Diospyros mannii Hiern (Ebenaceae). Their structures were established by NMR and MS data. This is the first report of asperglaucide from the family Ebenaceae, while mannic acid (1) and xylopic acid (2) are the first ent-kaurane diterpenes isolated from this family. Their chemotaxonomic value is discussed.

A new cycloartane triterpenoid named conocarpol (1) was isolated from the stem bark of Diospyros conocarpa, together with the known compounds aridanin (2), lupeol (3), betulin (4), betulinic acid (5), stigmasterol (6), and stigmasterol 3-O-β-d-glucopyranoside (7). Their structures were established on the basis of 1D and 2D NMR spectroscopy as well as mass spectrometry. Aridanin (2) is reported for the first time in the family Ebenaceae, and conocarpol (1) represents the first cycloartane triterpene within this family.

Eight compounds were isolated from the stem bark of Antrocaryon klaineanum, and their structures determined by chemical and spectroscopic methods. Among these compounds, the ergostane-type antrocarine E (1a) is a new compound, although the structure had already been published by mismatching the spectroscopic data with those of 2. In this paper, we are reporting the valid spectroscopic values for antrocarine E and X-ray diffraction results.

Five new alkylbenzoquinone derivatives, ardisiaquinones L–P ( 1–5 ) along with the known ardisiaquinone K were isolated from the MeOH extracts of leaves and stems of Ardisia kivuensis Taton (Myrsinaceae). Ardisiaquinones L, M and N were isolated from the leaves while ardisiaquinones K, O and P were obtained from the stem. Ardisiaquinone O was obtained in mixture with ardisiaquinone N, and P together with K, respectively. Their structures were elucidated on the basis of spectroscopic data. All the compounds showed cytotoxicity against Artemia salina and moderate antimicrobial activity.