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Ripe figs, barks, and wood of Ficus vallis-choudae are used in traditional medicine against several conditions including nausea and malaria. However, its use is still to be scientifically documented and validated. Hence, the aim of the present work was to evaluate the antiplasmodial activity of the dichloromethane-methanol (DCM-MeOH (1:1)) crude extract, their hexane, dichloromethane, ethyl acetate, and methanoli fractions, as well as the isolated chemical constituents. The chemical study of the DCM-MeOH (1:1) crude extract of F. vallis-choudae figs led to the isolation of fifteen (15) known compounds identified based on their spectroscopic data [one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR), mass spectrometry] and by comparison of these data with those reported in the literature. Some of the isolated compounds were assessed in vitro for their antiplasmodial activity against Plasmodium falciparum chloroquine-sensitive 3D7 (Pf3D7) and multidrug-resistant Dd2 strains. The dichloromethane fraction exhibited very good antiplasmodial activity against both strains with IC50 values of 13.86mug/mL and 8.18mug/mL, respectively. Among the tested compounds, wighteone (2) was the most active against P. falciparum 3D7 (IC50=24.6±1.5muM) and Dd2 (IC50=11.9±2.4muM) strains. The obtained results could justify the traditional uses of F. vallis-choudae against malaria. Wighteone appears to be the most active ingredient. However, further consideration of this compound as starting point for antimalarial drug discovery will depend upon its selectivity of action towards Plasmodium parasites. HIGHLIGHTS: 15 (fifteen) compounds were isolated from the dichloromethane-methanol extract of Ficus vallis-choudae. Their structures were determined on the basis of their spectroscopic data. The dichloromethane fraction showed promising activities on the Pf3D7 and PfDd2 strains with IC50 values of 13.86 and 8.18g/mL, respectively. Wighteone was the most active compound against PfDd2 (IC50=11.9±2.4muM). © 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

The polar fraction of the MeOH extract of the roots of Corrigiola litoralis subsp. telephiifolia (Pourr.) Briq. (Caryophyllaceae) was investigated for its constituents and two previously unreported...

The investigation of the CH2Cl2-MeOH (1:1) extract of Peperomia vulcanica which showed antileishmanial activity during preliminary screening led to the isolation of two previously unknown compounds named peperolignan (1) and peperotannin (2) along with 13 known compounds. Their structures were determined on the basis of their spectroscopic data. The isolated compounds were assessed in vitro for their antileishmanial and antiplasmodial activities against Leishmania donovani 1S (MHOM/SD/62/1S) promastigotes and the Plasmodium falciparum chloroquine-sensitive 3D7 strain (Pf3D7), respectively. They were also assessed for their cytotoxicity on Raw 264.7 macrophage cells. The mixture of 4-hydroxy-2-[(3,4-methylenedioxyphenyl)nonanoyl]cyclohexan-1,3-dione and 4-hydroxy-2-[(3,4-methylenedioxyphenyl) undecanoyl] cyclo-hexane-1,3-dione (10a and 10b) exhibited potent antiplasmodial activity (IC50 = 0.35 μg/mL) with selectivity index higher than 10-fold (SI = 63.4) and moderate leishmanicidal activity (IC50 = 12.17 μg/mL) with very low selectivity index (SI = 1.82). The obtained results could provide an extent of validation to the traditional uses of Peperomia vulcanica for the treatment of malaria in endemic areas.

Phytochemical investigation of the methanol extracts from the leaves and bark of

Phytochemical investigation of the seeds of Pentaclethra macrophylla led to the isolation of a mixture of two new aromatic monoterpene glycosides, pentamacrophylloside A (1a) and pentamacrophylloside B (1b), together with six known secondary metabolites: Comososide (2), secopentaclethroside (3), caffeoylputrescine (4), β-sitosterol-3-O-β-D-glucopyranoside (5), 2-hydroxymethyl-5-(2-hydroxypropan-2-yl)phenol (6), and sucrose (7). Their structures were elucidated mainly by extensive spectroscopic analysis (1D and 2D NMR), high-resolution mass spectrometry and by comparison of their spectral data with those of related compounds. The extracts and compounds 3 and 4 were screened for their antimicrobial activity. The n-BuOH fraction showed a weak effect against three microbial strains: Candida albicans (MIC: 256 μg/mL), Enterococcus faecalis (MIC: 512 μg/mL), and Proteus mirabilis (MIC: 512 μg/mL) while no significant inhibition was observed for pure compounds when compared to ketoconazole and ciprofloxacin used as references. Furthermore, the ethnobotany and pharmacology of this plant are reviewed, and the chemophenetic significance of the isolation of the above secondary metabolites is discussed. This is the first report on the isolation of aromatic monoterpenoids from a plant of the genus Pentaclethra.

Medicinal plants are known as sources of potential antibacterial compounds including alkaloids. The aim of the present study was to evaluate the antibacterial activities of the extract, fractions, and some secondary metabolites isolated from the leaves of Crinum glaucum A. Chev. (Amaryllidaceae). The antibacterial activities were performed with the ethanol (EtOH) extract, as well as with ethyl acetate (EtOAc) and n-butanol (n-BuOH) fractions. Repeated column chromatography of the fractions led to the isolation of several compounds and their structures were elucidated mainly by means of extensive spectroscopic analysis [(one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR), mass spectrometry)] and the comparison with published data. This includes eleven alkaloids: (3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (1), lycorine (2), ungeremine (3), ambelline (4), macronine (5), 5,6-dihydrobicolorine (6), trisphaeridine (7), hippadine (8), adenosine (9), arolycoricidine (10), pratorimine (11); two steroids: β-sitosterol (12), β-sitosterol-3-O-β-D-glucopyranoside (14) and one triterpene: oleanolic acid (13). Apart from lycorine (2), all these secondary metabolites are isolated from C. glaucum for the first time. The in vitro antibacterial activity of the EtOH extract, and the n-BuOH and EtOAc fractions as well as compounds 2, 3, 6 and 9 against pathogenic bacteria was performed. All extracts and fractions showed varying levels of antibacterial properties against at least one of the bacteria strains tested. The n-BuOH fraction was the most active extract with the lowest minimal inhibitory concentration (MIC) value of 64 µg/mL against Enterococcus faecalis. For pure compounds, the best MIC (8 µg/mL) was obtained with ungeremine (3) against Enterococcus faecalis and Pseudomonas aeruginosa. Our results show the antimicrobial potential of C. glaucum and scientifically validate its uses in traditional medicine against infectious diseases including cough and sexually transmitted infections. Ungeremine seems to be the antimicrobial active ingredient of this medicinal plant.

Phytochemical investigation of the methanol extracts from the leaves and bark of Senna siamea resulted in the isolation of one new flavone C-glycoside: apigenin-8-C-[6''-(E)-feruloyl]-β-D-glucopyranoside] (1), together with sixteen known compounds including quercetin-3-O-α-L-rhamnoside (2), vitexin (3), isovitexin (4), quercetin-3-O-β-D-glucopyranoside (5), quercetin-3-O-β-D-arabinopyranoside (6), quercetin (7), kaempferol (8), methyl inositol (9), sucrose (10), betulinic acid (11), vanillic acid (12), stigmastane-3β,6α-diol (13), aurantiamide acetate (14), robinetinidol (15), catechin (16) and epicatechin (17). The structures of these compounds were established on the basis of their spectroscopic (1 D and 2 D NMR) and mass spectrometric (ESI-TOF-MS) data. The methanol extracts, fractions and some of the isolated compounds were screened for their antimicrobial properties against five microbial strains. The methanol extract and the ethyl acetate fraction from the bark showed very weak antifungal activity against C. glabrata with the same MIC value of 128 μg/mL. Compound 7 was weakly active against C. albicans with MIC of 32 μg/mL.

The polar fraction of the MeOH extract of the roots of

Aim To identify the bioactive hepatoprotective components of the ethanol extract of Pentaclethra macrophylla stem bark using in vitro and in vivo approaches. Methods The bioguided-fractionation of the ethanol extract was based on the substances’ capacity to prevent in vitro, the lipid peroxidation of hepatocytes’ membranes induced by hydrogen peroxide. For the in vivo hepatoprotective test, mice were treated orally with the ethyl acetate (EtOAc) fraction of the ethanol extract at doses of 50 and 75 mg/kg/day for one week and subjected to d -galactosamine/lipopolysaccharide (GaIN/LPS)-induced hepatotoxicity. Blood samples were collected for alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), TNF-α and IL-1β assays. The liver was harvested for histological and biochemical (proteins, glutathione (GSH), catalase and superoxide dismutase (SOD)) analysis. Results The ethanol extract and fractions induced concentration-dependent inhibition of lipid peroxidation (IC50: 3.21–48.90 μg/mL) greater than that of silymarin (IC50: 117.4 μg/mL). The purification of the sub-fractions of EtOAc fraction yielded: (7R)-7-hydroxyhexacosanoic acid (1), (7R)-1-(7-hydroxyhexacosanoyl) glycerol (2), bergenin (3), 11-O-galloylbergenin (4), 2-hydroxymethyl-5-(2-hydroxypropan-2-yl)phenol (5), β-sitosterol 3-O-β- d -glucopyranosyl (6) and β-sitosterol (7)), among which 11-O-galloylbergenin (IC50:1.8 μg/mL) was the most effective. The EtOAc fraction significantly reduced the serum level of ALAT, ASAT and TNF-α in vivo. This EtOAc fraction increased the liver protein content and protected the liver against structural damages, but did not boost the endogenous antioxidant parameters. Conclusion The stem bark of Pentaclethra macrophylla possesses hepatoprotective effects that may result from its capacity to inhibit lipid peroxidation and could be attributed to its active components 3, 4 and 2.

A new triterpenoid saponin (Mimonoside D: 3-O-��-L-arabinopyranosyl-3��-hydroxyolean-12-en-28-oic acid 28-O-��-D-xylopyranosyl-(1���2)-��-D- glucopyranoside ester (1)) was isolated from the aerial parts of Mimosa diplotricha Sauvalle together with nine known compounds: 7,4���-dihydroxyflavone (2), kaempferol (3), lupeol (4), betulinic acid (5), ��-sitosterol (6), ��-sitosterol-3-O-��-D-glucopyranoside (7), lutein (8), 5,2���-dihydroxy-7,4���,5���-trimethoxyflavone (9) and vitexin (10). Their structures were elucidated on the basis of spectroscopic (1 D and 2 D nuclear magnetic resonance) and high-resolution mass spectrometric data as well as by comparison of their spectral data with those of related compounds. Compounds 2, 7 and 8 had already been isolated from M. diplotricha, while compounds 3, 4, 5 and 6 have been isolated from other Mimosa species. Compound 2 moderately inhibited Proteus mirabilis (MIC = 32 ��g/mL), weakly inhibited Pseudomonas aeruginosa (MIC = 64 ��g/mL) and very weakly inhibited Staphylococcus aureus (MIC = 128 ��g/mL) and Enterococus faecalis (MIC = 128 ��g/mL).

Drug resistance due to the extensive abuse and over-use of antibiotics has become an increasingly serious problem and researchers started to use plants as an alternative source of new antibiotics. The aim of the present study was to assess the antimicrobial properties of secondary metabolites isolated from A. liebrechtsiana. A new secoiridoid derivative, anthocleistenolide B (1), along with three known compounds, the monoterpene diol, djalonenol (2), the xanthone O-glycoside, decussatin 1-O-β-D-glucopyranoside and the fatty acid, dotriacontanoic acid (4) was isolated from the leaves and bark of this plant. Their structures were elucidated by extensive analysis of spectroscopic (1D and 2D NMR) and mass spectrometric data. The isolated compounds were screened for their antimicrobial properties against five strains of bacteria (two gram positive: Staphylococcus aureus 29213, Enterococcus faecalis ATCC 25922 and three gram negative: Escherichia coli ATCC51299, Proteus mirabilis (isolate), and Pseudomonas aeruginosa QC76110), but all were inactive.

A new steroid derivative, (24S)-3β-hydroxy-7β-methoxyergost-5-ene (1), was isolated along with eleven known compounds: 7α-hydroxysterol (2), β-sitosterol (3), oleanolic acid (4), betulinic acid (5), lupeol (6), swertiaperennin (7), decussatin (8), tetracosanoic acid (9) β-sitosterol-3-O-β- d -glucopyranoside (10), (2R,3S)-2,3-dihydro-2-(3,4-dimethoxyphenyl)-3-hydroxymethyl-5-(2-formylvinyl)-7-hydroxybenzofuran (11) and acacetin 6-C-β- d -glucopyranoside (12) from the tree bark and leaves of Anthocleista liebrechtsiana De Wild & T. Durand. Their structures were elucidated on the basis of spectroscopic (1D and 2D NMR) and mass spectrometric data. Compounds 2 and 7–10 have already been isolated from the genus Anthocleista and 3–6 from the Loganiaceae family. The isolated secondary metabolites were screened for their antimicrobial properties but only compound 12 showed moderate activity against Pseudomonas aeruginosa. Furthermore, the chemotaxonomic significance among Anthocleista species is discussed.

Lipid peroxidation plays a pivotal role in the pathogenicity and maintenance of hepatitis. Thus, substances protecting hepatocyte membranes from lipid peroxidation are of great importance in the management of hepatotoxicity and hepatitis. The present work deals with the in vitro hepatoprotective activity of the methanol extract of Desmodium uncinatum, its sub-fractions, the major isolated compounds and some of their semi-synthetic derivatives in order to study structure activity relationships. Using hydrogen peroxide (H2O2)-induced lipid peroxidation of hepatocyte membranes as a model, the hepatoprotective-guided phytochemical survey of the methanol extract of aerial parts of D. uncinatum was carried out by successive column chromatography. One of the most active compounds (Isovitexin) was chemically transformed to yield new semi-synthetic. The identification of isolated and semi-synthetic compounds was performed using NMR techniques, mass spectrometry and by comparison of their data with those reported in the literature. The n-butanol fraction was the most effective (IC50: 22.9 μg/mL) compared to the crude methanol extract (IC50: 43.6 μg/mL) and other fractions. The n-butanol sub-fractions FA (containing non-phenolic compounds) and FB (mainly containing phenolic compounds) exhibited respective IC50 of 14.36 and 128.2 μg/ml. Purification of FA yielded 3-O-β-D-glucopyranosyl-β-sitosterol (1), 3-O-β-D- 2-acetyl-amino-2-deoxyglucopyranoxyloleanoic acid (2), (2S, 3S, 4R, 7R, 8Z)-1-O-β-D-glucopyranosyl-2-[(R)-2'-hydroxyarachidoylamino]-docosan-8-ene-3,4,7-triol (4), spiraeamide (5), mannitol (6), while FB afforded essentially three C-glycosylflavonoids namely isovitexin (7), vitexin (8) and vicenin-3 (9). Chemical transformations (methylation, allylation and prenylation) of isovitexin afforded five new semi-synthetic derivatives: 4',5,7-O- trimethyli-sovitexin (10), 4'-O-allylisovitexin (11), 4',7-O-diallylisovitexin (12), 4'-O-prenylisovitexin (13) and 8-C-prenyl-4',7-O-diprenylisovitexin (14). The screening of these derivatives revealed that allylation did not significantly affect the hepatoprotective activity while methylation, prenylation, number and position of sugar moieties on the A ring of flavonoids significantly reduced it. Results demonstrated that the n-butanol fraction obtained from the methanol extract of Desmdium uncinatum may possess hepatoprotective activity due to its content in C-glycosylflavonoids and cerebrosides. Hydroxyl groups in C-glycosylflavonoids are important for their lipid peroxidation inhibitory activity.

The development and spread of resistance to currently available antibiotics is a major drawback in the treatment of microbial infections. Salmonellosis for example remains among the most common cause of morbidity and mortality in developing countries. This study aimed to evaluate the antisalmonellal potential of extracts, fractions, isolated compounds and semi-synthetic flavonoids from Tristemma hirtum P. Beauv. Bioguided fractionation by column chromatography of the EtOAc and n -BuOH fractions led to the isolation of eleven compounds including two new esterified glucuronide flavonoids namely: luteolin-3′-O-β-D-glucuronopyranosylbutyl ester (1), a mixture of compound 1 and quercetin-3-O-β-D-glucuronopyranosylbutyl ester (2). Chemical transformation mainly based on the prenylation of 6-hydroxyapigenin-7-O-β-D-glucopyranoside (5) afforded four new semi-synthetic flavonoid derivatives namely: 6, 4'-O-diprenylapigenin-7-O-β-D-glucopyranoside (5a), 8-C-prenyl-6, 4'-O-diprenylapigenin-7-O-β-D-glucopyranoside (5b), 8-C-prenyl-4'-O-prenylapigenin-7-O-β-D-glucopyranoside (5c), 4'-O-prenylapigenin-7-O-β-D-glucopyranoside (5d). The chemical structures of these compounds were assigned using NMR techniques, mass spectrometry and by comparison of their data with reported ones. The antisalmonellal activity was assessed by determining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) using serial microdilution methods. The results showed that the MeOH extract and EtOAc fraction were active against all the bacteria tested with MICs ranging from 24 to 1536 µg/mL. Seven isolated compounds and three semi-synthetic compounds tested showed MIC values ranging from 16 to 256 µg/mL. Compounds 1, 3, 5a, 5c and 11 displayed the most potent antisalmonellal properties but were generally less potent than those of reference drugs. The activity of extracts and isolated compounds could be used as the starting point for the development of alternative phytodrugs against salmonellosis.

A new saponin, 3-O-β-d-3-oxo-glucopyranosyl-ursa-12,20(30)-diene-27,28-dioic acid (1), was isolated from the methanol extract of stem bark of Crossopteryx febrifuga together with the known 3β-d-glucopyranosyl-ursa-12,20(30)-diene-27,28-dioic acid (2), shanzhiside methyl ester (3), shanzhiside (4), β-sitosterol (5), β-sitosterol-3-O-β-d-glucopyranoside (6), ursa-12,20(30)-diene-27,28-dioic acid (7), hederagenin (8), and oleanolic acid (9). The structures were established by comprehensive interpretation of their spectral data 1D- (1H and 13C), 2D-NMR (1H-1H COSY, HMQC, HMBC), spectroscopic, and electrospray ionisation time-of-flight mass spectrometry analysis. The isolated compounds and extracts were screened for their antibacterial properties. Although the EtOAc and n-BuOH extracts exhibited considerable antibacterial activity against Pseudomonas aeruginosa with minimum inhibitory concentration (MIC) value of 32 μg/mL, compounds 2 and 8 showed moderate activity against Enterococcus faecalis with MIC values of 256 and 128 μg/mL, respectively. The new compound (1) exhibited a moderate antibacterial activity against Staphylococcus aureus with an MIC value of 512 μg/mL.

A new sulfated steroidal derivative (fruticogenin A: 1-sulfo-australigenin-3-sodium sulphate, 1) and three new steroidal saponins named fruticoside K (3-sulfo-spirostan-25(27)-ene-1β,3β-diol-1-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-fucopyranoside], 2), fruticoside L (3-sulfo-spirostan-25(27)-ene-1β,3β,6α-triol-1-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-fucopyranoside], 3) and fruticoside M (spirostan-25(27)-ene-1β,3α-diol-1-O-[α-L-rhamnopyranosyl-(1 → 2)-α-L-rhamnopyranoside], 4) were isolated from the aerial parts of Cordyline fruticosa L. var. strawberries. Their structures were established on the basis of 1D and 2D NMR data, mass spectrometry and chemical methods. Compounds 2 and 4 exhibited weak cytotoxicity against melanoma (A375), breast adenocarcinoma (MDA-MB-231), and colon carcinoma (HCT116) human tumor cell lines.

Fifteen triterpenoid saponins including five new compounds (Mannioside B: 3β-[(β- d -glucopyranosyl)oxy]urs-12-en-28-oic acid α- l -rhamnopyranosyl-(1 → 4)-β- d -glucopyranosyl-(1 → 6)-β- d -glucopyranosyl ester (1), mannioside C: 3β-[(β- d -glucopyranosyl)23-dioxy]urs-12-en-28-oic acid α- l -rhamnopyranosyl-(1 → 4)-β- d -glucopyranosyl-(1 → 6)-β- d -glucopyranosyl ester (2), mannioside D: 3β,23-dihydroxyurs-12-en-28-oic acid β- d -glucopyranosyl-(1 → 6)- β- d -glucopyranosyl ester (3), mannioside E: 3β-hydroxy-23-oxolup-20(29)-en-28-oic acid α- l -rhamnopyranosyl-(1 → 4)-β- d -glucopyranosyl-(1 → 6)-β- d -glucopyranosyl ester (4) and mannioside F: (22S)-27β-[(β- d -glucopyranosyl)oxy]-22-hydroxyprotosta-12,24-dien-3β-yl β- d -glucopyranoside (5)) were isolated from the leaves of Schefflera mannii (Hook.f.) Harms. Their structures were established on the basis of 1D and 2D NMR data, mass spectrometry and chemical methods. The major isolated compounds were tested for their antiproliferative activity on human malignant epithelial (HeLa) cells but were not efficient at the concentration of 33 mM.

The ethyl acetate extract from the whole plant of Crinum biflorum Rottb. Showed a moderate activity against Enterococcus faecalis. Its phytochemical investigation led to the isolation of a new flavan-3-ol derivative namely (2R,3R)-3-hydroxy-7-methoxy-3′,4′-methylenedioxyflavan, together with (2S)-7-hydroxy-3′,4′-methylenedioxyflavan, (2R,3R)-7-methoxy-flavan-3-ol, (2S)-7-hydroxy-3′,4′-dimethoxyflavan, 3′,7-dihydroxy-4′-methoxyflavan, 4′,7-dimethoxy-3′-hydroxyflavan, farrerol, β-sitosterol, β-sitosterol-3-O-β-D-glucopyranoside, oleanolic acid, kaempferol, pancratistatin, lupeol, aurantiamide acetate, Narciprimine and 2,3-dihydroxypropyl palmitate. Their structures were elucidated mainly by extensive spectroscopic analysis and comparison with published data. The absolute configuration of the new metabolite was determined by electronic circular dichroism (ECD) analysis and comparison of optical rotation. Some of the isolated compounds were tested for their antimicrobial activity but no inhibition was observed.

From the EtOAc fraction of the methanol extract of the stem barks of Baillonella toxisperma (Sapotaceae), eight compounds were isolated using column chromatography techniques. Their structures were established on the basis of 1D and 2D-NMR data and comparison with data published in the literature. The MeOH extract, n-BuOH and EtOAc fractions together with some pure compounds (4, 5, 7, 8) were screened for their radical scavenging activity using the2,2-diphenyl-1- picryl-hydrazyl-hydrate (DPPH) free radical in order to get preliminary information about the antiradical capacities of this plant.Keywords: Baillonella toxisperma;Sapotaceae; DPPH; Antiradical activity

Phytochemical investigation of the roots of Furcraea bedinghausii Koch. Led to the isolation of a mixture of two new homoisoflavones, 5,7-dihydroxy-3-(3,4-methylenedioxybenzyl)-chromone (4a) and 5,7-dihydroxy-3-(4-methoxybenzyl)-chromone (4b), together with the known β-sitosterol (1), 7,4'-dihydroxyhomoisoflavane (2), dihydrobonducellin (3), kaempferol (5), 5,7-dihydroxy-3-(4-hydroxybenzyl)-chromone (6), 1-linoleylglycerol (7), 6’-linoleyl-3-O-β-D-glucopyranosyl-β-sitosterol (8), trans-3,3’,5,5’-tetrahydroxy-4’-methoxystilbene (9), yuccaol C (10), yuccaol D (11), 3-O-b-D-glucopyranosyl-b-sitosterol (12), 4-[6-O-(4-hydroxy-3,5-dimethoxybenzoyl)-β-D-glucopyranosyloxy]-3-methoxybenzoic acid (13) and two pairs of steroidal saponins: (25R)-2α-3β–dihydroxy-5α-spirostan-12-one 3-O-β-D-glucopyranosyl-(1→2)-O-[β-D-xylopyranosyl-(1→3)]-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (14a) and (25R)-2α-3β–dihydroxy-5α-spirost-9-en-12-one 3-O-β-D-glucopyranosyl-(1→2)-O-[β-D-xylopyranosyl-(1→3)]-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (14b), (25R)-3β–hydroxy-5α-spirostan-12-one 3-O-β-D-glucopyranosyl-(1→2)-O-[β-D-xylopyranosyl-(1→3)]-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (15a) and (25R)-3β–hydroxy-5α-spirost-9-en-12-one 3-O-β-D-glucopyranosyl-(1→2)-O-[β-D-xylopyranosyl-(1→3)]-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (15b). Their structures were elucidated by interpretation of spectral data and by comparison with literature.

A new C-glycosylflavone, drymaritin E (6-C-(3-keto-β-digitoxopyranosyl)-4'-O-(β-D-glucopyranosyl)-7-methoxyl-5,4'-dihydroxylflavone) 1 was isolated from the oily upper phase (SU) of the MeOH extract from aerial parts of Drymaria cordata together with two known compounds (cassiaoccidentalin A 2 and anemonin 3) and an inseparable mixture of two known C-glycosylflavones 5,4'-dihydroxy-7-methoxyflavone-6-C-(2''-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside 4a and 5,7,3',4'-tetrahydroxyflavone-6-C-(2''-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside 4b. The alkaline hydrolysis of 3 led to a new hemisynthetic derivative, sodium anemonate (sodium 2-((1'E) 2'-sodium-carboxylate-vinyl)-5-oxo-cyclohex-1-ene carboxylate) 3a. The chemical structures were determined by spectroscopic methods ((1)H NMR, (13)C NMR, (1)H-(1)H COSY, HMBC, HSQC, and NOESY) and mass spectrometry (ESI-MS). C-glycosylflavones had significant free radical-scavenging activities on the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). However, SU and compounds 3 and 3a exhibited no activity. In particular, compound 1 exhibited a concentration-dependent radical scavenging activity on DPPH with EC50 of 31.43 µg/mL.

A new triterpenoid saponin named bafouoside C 3-O-β- d -glucopyranosyl-(1 → 4)-[β- d -galactopyranosyl-(1 → 2)]-β- d -glucuronopyranosyloleanolic acid 28-O-β- d -glucopyranosyl ester; (1), together with five known compounds 3-O-β- d -galactopyranosyl-(1 → 2)-β- d -glucuronopyranosyloleanolic acid (2), 23-hydroxyursolic acid (3), 28-O-α- l -rhamnopyranosyl-(1 → 4)-O-β- d -glucopyranosyl-(1 → 6)-O-β- d -glucopyranosyl-23-hydroxyursolic acid (4), 3-O-β- d -glucopyranosyl-23-hydroxyursolic acid (5), and 3-O-α- l -arabinopyranosyl-23-hydroxyursolic acid (6), were isolated from the roots of Cussonia bancoensis Aubrev. & Pellegr. Their structures were established on the basis of 1D- and 2D NMR data, mass spectrometry and chemical methods. The NMR data of the known compounds, as far as we know, are herein reported for the first time in CD3OD. Compound 3 exhibited a weak cytotoxic activity against MDA-MB 231 human breast adenocarcinoma, A375 human malignant melanoma, and HCT116 human colon carcinoma cell lines.

A new tetracyclic triterpenoid [4,4,24-trimethylcholesta-Δ8,9;14,15;24,28-trien-3β,11β,12α-triol-12-acetate, 3-sulfate] sodium salt (1), together with eight known compounds including ergosterol 5α,8α-endoperoxide (2), 1,9-dihydroxy-3-methoxy-2-methylpterocarpan (3), 3-O-β-D-2-acetyl-amino-2-deoxyglucopyranoxyloleanoic acid (4), hydnocarpin (5), derrone (6), isovitexin (7), erythrinin C (8), and 5,4`-dihydroxy-2``-hydroxyisopropyldihydrofurano [4,5:7,8]-isoflavone (9), were isolated from the EtOAc soluble fraction of the methanol extract of aerial part of Desmodium uncinatum collected in the western highland of Cameroon. The structures of these compounds were established by comprehensive interpretation of their spectral data mainly including 1D- (1H and 13C), 2D-NMR (1H-1H COSY, HMQC, HMBC) spectroscopic and ESI-TOF-MS mass spectrometric analysis. The isolation of an integracide-like compound from plant origin is a very unusual finding.

A new clerodane diterpenoid, bafoudiosbulbin H (1), was isolated from the flowers of Dioscorea bulbifera L. var sativa. Its acetylation using acetic anhydride-pyridine and catalytic amount of 4-DMAP at 60 °C yielded bafoudiosbulbin H acetate (2) together with a clerodane with an unprecedented acylation pattern (bafoudiosbulbin H1, 3). The reaction of the known bafoudiosbulbin G (4) in the same conditions yielded demethylbafoudiosbulbin G (5). Structural elucidation of 5 led to the revision of the stereochemistry previously assigned to 4. Structures were elucidated using spectroscopic techniques, including 1D and 2D NMR (1H, 13C, HSQC, COSY, HMBC, ROESY, NOESY) and mass spectrometry (HRESIMS).

Three new triterpenoid saponins, elucidated as 3-O-β-D-glucopyranosyloleanolic acid 28-O-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside (parkioside A, 1), 3-O-[β-D-apifuranosyl-(1→3)-β-D-glucopyranosyl]oleanolic acid 28-O-[β-D-apifuranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)β-D-xylopyranoside (parkioside B, 2) and 3-O-β-D-glucuronopyranosyl-16α-hydroxyprotobassic acid 28-O-α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside (parkioside C, 3), were isolated from the n-BuOH extract of the root bark of Butyrospermum parkii, along with the known 3-O-β-D-glucopyranosyloleanolic acid (androseptoside A). The structures of the isolated compounds were established on the basis of chemical and spectroscopic methods, mainly 1D and 2D NMR data and mass spectrometry. The new compounds were tested for both radical scavenging and cytotoxic activities. Compound 2 showed cytotoxic activity against A375 and T98G cell lines, with IC(50) values of 2.74 and 2.93 μM, respectively. Furthermore, it showed an antioxidant activity comparable to that of Trolox or butylated hydroxytoluene (BHT), used as controls, against 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), oxygen and nitric oxide radicals.

Two new oleanane-type triterpenes named ivorengenin A (=3-oxo-2α,19α,24-trihydroxyolean-12-en-28-oic acid; 1) and ivorengenin B (=4-oxo-19α-hydroxy-3,24-dinor-2,4-secoolean-12-ene-2,28-dioic acid; 2), together with five known compounds, arjungenin, arjunic acid, betulinic acid, sericic acid, and oleanolic acid, were isolated from the barks of Terminalia ivorensis A. Chev. (Combretaceae). Their structures were established on the basis of 1D- and 2D-NMR data, and mass spectrometry. A biogenetic pathway to the formation of these compounds from sericic acid, isolated as the major compound from this plant, was proposed. The antioxidant activities of different compounds were investigated by means of the 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, and IC(50) values were calculated and compared with Trolox activity. Antiproliferative activities of the isolated compounds were also evaluated against MDA-MB-231, PC3, HCT116, and T98G human cancer cell lines, against which the compounds showed significant cytotoxic activities.

The aerial part of Rubus rigidus var. camerunensis (Rosaceae) is used to treat respiratory and cardiovascular disorders in the Cameroonian traditional medicine. The ethanol extract exhibited more potent antioxidant activity (E(max)s of 119% and 229% activity on DPPH and β-carotene test) than aqueous extract. Bioactivity-guided fractionation of the ethanol extract based on free radical-scavenging assay (DPPH assay) afforded five flavonoid glycosides (four flavonol glycosides and an anthocyanin) and three glucosides of 19α-hydroxyursane-type triterpenoid (two monomeric and one dimeric triterpenoids). The flavonoids were identified as kaempferol 3-O-(2″-O-E-p-coumaroyl)-β-D-glucopyranoside (1), kaempferol-3-O-β-D-glucopyranoside (astragalin, 2), kaempferol-3-O-α-L-arabinofuranoside (juglanin, 3), quercetin-3-O-β-D-glucopyranoside (isoquercitrin, 4), pelargonidin-3-O-β-D-glucopyranoside (callistephin, 5). The three triterpenoids were 2α, 3β, 19α, 23-tetrahydroxyurs-12-ene-28-O-β-D-glucopyranosyl ester (nigaichigoside F(1), 6), 2α, 3β, 19α-trihydroxyurs-12-ene-23-carboxyl-28-O-β-D-glucopyranosyl ester (suavissimoside R(1), 7) as monomeric triterpenoids and coreanoside F(1) (8) as a dimeric triterpenoid. The flavonoids exhibited potent antioxidant activities (66 to 93.56% against DPPH radical) and they were also active on β-carotene test. Coreanoside F(1) exhibited a 63% antioxidant activity, meanwhile the other two triterpenoids showed a weak activity. Three important facts on structure-activity relationship were observed: Compound 8, a dimeric triterpenoid glycoside, strongly enhanced antioxidant activity of its monomers, compound 3 with 3-O-α-L-arabinofuranyl has much more potent activity than compound 2 with 3-O-β-D-glucopyranosyl, and antocyanin (5) is more potent than its corresponding flavonol glycosides.

Three saponins, including two dimeric triterpenoid glucosides possessing an unusual skeleton, ivorenosides A and B, and a monomeric triterpenoid saponin (ivorenoside C), together with the known sericoside, were isolated from the bark of Terminalia ivorensis. Their structures were established on the basis of 1D and 2D NMR data, chemical methods and tandem MS-MS spectrometry as a dimer of β-D-glucopyranosyl-18,19-seco-2α,3β,19,19,24-pentahydroxyolean-12-en-28-oate and β-D-glucopyranosyl-2α,3β,19α,24-tetrahydroxyolean-12-en-28-oate (ivorenoside A, 1), a dimer of β-D-glucopyranosyl-18,19-seco-24-carboxyl-2α,3β,19,19-tetrahydroxyolean-12-en-28-oate and β-D-glucopyranosyl-2α,3β,19α,24-tetrahydroxyolean-12-en-28-oate (ivorenoside B, 2) and β-D-glucopyranosyl-2α,3β,19β,24-tetrahydroxyolean-11-oxo-olean-12-en-28-oate (ivorenoside C, 3). Ivorenosides A and B are the first examples in nature of dimeric triterpenoid saponins with a 18,19-seco E ring of one of the two units. These isolated compounds were evaluated for their antioxidant properties and further for their cytotoxic activity against four human cancer cell lines. Ivorenoside B and C exhibited scavenging activity against DPPH and ABTS(+) radicals with IC(50) values comparable with that of the standard drug Trolox and ivorenoside A showed antiproliferative activity against MDA-MB-231 and HCT116 human cancer cell lines with IC(50) values of 3.96 and 3.43 μM, respectively.

A new oleanane-type triterpene saponin, β- d -glucopyranosyl 2α,3β,6β-trihydroxy-23-galloylolean-12-en-28-oate (1), together with four known oleanane-type pentacyclic triterpenoids, combregenin (2), arjungenin (3), arjunglucoside I (4), and combreglucoside (5) were isolated from the stem bark of Combretum molle. Their structures were established mainly on the basis of 1D and 2D NMR spectral data. Compounds 1–3 exhibited more significant activity against carrageenan-induced paw edema in rat compared to compounds 4 and 5.