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The phytochemical investigation of the methanol extract of the stem bark of Gilbertiodendron dewevrei led to the isolation of two new secondary metabolites, 5,7-dihydroxy-4′-methoxyisoflavan-2,4-dione (1) and 23-hydroxy-2-tricosanone (2) along with 19 known compounds (3–21). The structure of these compounds were established by interpretation of their spectral data, mainly HR-TOFESIMS, 1 D NMR (1H, 13C and DEPT) and 2 D NMR (1H–1H COSY, HSQC, HMBC, and NOESY), and by comparison with those reported in the literature. The methanol extract and some isolates were screened for their antiradical, antibacterial, and inhibitory properties against acetylcholinesterase. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of Alsophila manniana rhizomes led to the isolation of twelve known compounds, including two triterpenes (1 and 2), four steroids (3 – 6), one glycerol (7), three phenols (8 – 10), and two flavonoids (11 and 12). Their structures were elucidated by analyses of the NMR and MS data and by comparisons with those in the literature. Their antibacterial and cytotoxic activities were evaluated against Escherichia coli , Klebsiella pneumoniae , Staphylococcus aureus , and Bacillus subtilis; and on human lung A549, cervical HeLa, and breast MCF-7 cancer cell lines, respectively. Fractions F D and F F had significant activities against E. coli (MIC = 75 μg/mL) and K. pneumoniae (MICs = 75 and 37.5 μg/mL). Compounds 3 and 7 – 12 had moderate antibacterial activities with MIC values ranging from 75 to 150 μg/mL against the bacteria. All samples were inactive against all tested human cancer cell lines, even at 100 μg/mL. This is the first investigation of the chemical constituents of A. manniana , as well as the first report of compounds 3 , 7 , and 10 – 12 from the genus Alsophila. The chemotaxonomic significance of these compounds is discussed. [Display omitted] • First phytochemical investigation of a medicinal plant of Cameroon, Alsophila manniana. • Twelve secondary metabolites identified by NMR, MS and literature. • Excellent antibacterial activity MIC 37.5 and 75 μg/mL by fractions F F and F D. • The chemotaxonomic significance of these compounds was discussed. [ABSTRACT FROM AUTHOR]

An extensive phytochemical study on the combined methanolic extracts from the stem barks and roots of Phyllopentas schimperi (Hochst.) Y. D. Zhou & Q. F. Wang (syn. Pentas schimperi (Hochst.) Wieringa) led to the isolation of a new anthraquinone, schimperiquinone C (1) along with nineteen known secondary metabolites 2 – 20. The structures of all the isolated compounds were elucidated through spectroscopic techniques including 2D NMR. The new compound and the less common secondary metabolites 2 – 17 were tested for their pharmacological properties. Compounds 4 , 5 and 6 exhibited significant antioxidant and lipoxygenase inhibition activities, whereas compounds 2 – 5 , 7 – 10 , 12 and 17 had a potent urease inhibitory activity. Compounds 8 and 10 had the best urease inhibitory activities as compared to thiourea. Compounds 3 , 9 , 11 , 12 and 17 are reported for the first time from the genus Pentas. The chemotaxonomic significance of the isolated compounds was discussed. Our results could be used for the chemotaxonomy of this species within the genus Pentas and for the Rubiaceae family. The obtained results suggested that some constituents from this plant may be used as such or in the form of their derivatives for the treatment of ulcer. [Display omitted] • A new anthraquinone, along with 19 known compounds were isolated from P. schimperi. • Their structures were fully elucidated using NMR and MS analyses. • This is the first report of compounds 3 , 9 , 11 and 12 from genus Pentas. • Compounds 4 , 5 and 6 displayed strong antioxidant potencies. • Compound 10 displayed the most potent urease inhibitory activity. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the methanolic extract of the leaves of Hymenocardia acida (Euphorbiaceae) resulted in the isolation of twelve known secondary metabolites including flavonolignan (1), coumarin (2), chromone (3), C -glucosylated flavonoid (4), bisphenylpropanoid (5), triterpenoids (6 – 9) and steroids (10 – 12), respectively. Their structures were elucidated by comparison of their physical and spectroscopic data with those reported in literature. This is the first report on isolation of compounds 1 – 5 and 10 from the family Euphorbiaceae. The chemotaxonomic significance of these compounds has been discussed. Hydnocarpin (1), 7-hydroxycoumarin (2), 5,7-dihydroxy-2- n -pentacosanylchrom-4-one (3), luteolin 6- C - β -D-glucopyranoside (4), katsumadin (5) and friedelanone (6), were evaluated in vitro for their anti - free radical scavenging activity as well as inhibitory potential against the enzyme urease. Compounds 4 and 5 exhibited potent anti-free radical scavenging activity (IC 50 = 20.20 ± 0.19 μM and 15.60 ± 0.22 μM, respectively), while compounds 1 – 4 showed significant urease inhibitory activity (IC 50 = 25.60 ± 0.59 μM, 33.20 ± 0.73 μM, 27.60 ± 0.69 μM and 26.60 ± 0.13 μM, respectively). • Twelve known secondary metabolites were isolated from the leaves of H. acida. • Their structures were identified using NMR and MS analyses. • First report of compounds 1 - 5 and 10 from the family Euphorbiaceae. • Luteolin 6-C- β -D-glucopyranoside and katsumadin exhibited potent antioxidant activity. • Compounds 1 - 4 , showed significant urease inhibitory activity. [ABSTRACT FROM AUTHOR]

A new ceramide named luteaceramide (1), along with sixteen known compounds including 3 α -hydroxy-27- p -(E)-coumaroyloxyursan-12-en-28-oic acid (2), 3 α -hydroxy-27- p -(Z)-coumaroyloxyursan-12-en-28-oic acid (3), 3- O -acetyl- α -amyrin (4), lupeol (5), a mixture of β -sitosterol (6) and stigmasterol (7), 24-methylenecycloartenol (8), hexacosanol (9), ergosterol 5 α ,8 α -endoperoxide (10), hexatriacontan-1-ol (11), 3 β -acetoxy-1 β ,11α-dihydroxyolean-12-ene (12), palmitic acid (13), tormentic acid (14), alphitolic acid (15), β -sitosterol-3-O- β -D glucopyranoside (16), and ursolazuroside 1 (17) were obtained after phytochemical investigation of the methanol extract of the fruits of Ficus lutea. The structure of the new compound was elucidated by analyses of their spectroscopic data including 1D and 2D-NMR, HREI-MS and chemical conversions. The MeOH crude extract had weak activity against Proteus mirabilis (MIC 2.5 mg/mL). Luteaceramide (1), lupeol (5) and hexacosanol (9) showed a moderate antibacterial activity against Escherichia coli with MIC ranging from 31 to 63 μg/mL while 1 was weakly active against Staphylococcus aureus , Enterococcus faecalis , and P. mirabilis with MIC between 125 and 250 μg/mL. Compounds 2 , 3 , 12 , 14 , 15 , and 17 are also reported for the first time from the genus Ficus. The chemotaxonomic significance of the isolated compounds was summarized. Our results on the isolation of a new ceramide (1), triterpenoids of ursan (2 – 4 , 14 and 17)-, lupan (5 and 15)-, oleanan (12)-, and cycloartan (8)-types, steroids (6 , 7 , 10 and 16), alcohols (9 and 11), and a fatty acid (13) from F. lutea Vahl are in good agreement with the classification and the chemotaxonomy of this species for the genus Ficus and for the family Moraceae. The phytochemical analyses of plant species of the genus Ficus in most of the cases provided the isolation of ceramides. This class of secondary metabolites could be considered as one of the markers of the genus Ficus. [Display omitted] • Seventeen compounds were obtained from the fruits of Ficus lutea Vahl. • Characterization of a new ceramide while six known compounds were new in F. lutea. • The chemotaxonomic significance of the isolated compounds was summarized. • Luteaceramide had moderate antibacterial activity against Escherichia coli. [ABSTRACT FROM AUTHOR]