A lupeol derivative and other isolates with antiplasmodial activity from the stem root of Stapf. (Apocynaceae).

is a plant from western and eastern areas of African continent and is widely used in folk medicine for the treatment of various diseases including malaria. Herein, one previously undescribed acylated triterpene (), together with five already published natural products (-) were removed from its roots. The chemical structures of these compounds were determined by spectroscopic and spectrometric means (NMR, HRESIMS, IR and UV).

New acylated triterpenoid saponins from the roots of Acacia polyacantha Willd. (Fabaceae).

In our continuing search of saponins from the plants of Fabaceae family, phytochemical investigation of the roots of Acacia polyacantha, led to the isolation and structural characterization of six undescribed triterpenoid saponins, named polyacosides A-F (1-6). Their structures were established, using extensive analysis by NMR techniques, mainly 1D NMR (H, C, and DEPT) and 2D NMR (COSY, NOESY, HSQC, TOCSY and HMBC) experiments, HRESIMS and by comparison with the literature data, as 3-O-[β-d-xylopyranosyl-(1 → 4)- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)]-α-l-arabinopyranosyl]-21-O-[Cis-2-methoxycinnamoyl] machaerinic acid (1), 3-O-[β-d-xylopyranosyl-(1 → 4)- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)]-α-l-arabinopyranosyl]-21-O- [Cis-3,4-dimethoxycinnamoyl] machaerinic acid. (2), 3-O- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl]-21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (3), 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Cis-3,4-dimethoxycinnamoyl] machaerinic acid (4), 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Cis-2-methoxycinnamoyl] machaerinic acid (5) and 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (6).

Secondary metabolites of the leaves of N. Hallé (Rubiaceae) and their potential antiplasmodial activity.

One monoterpene indole alkaloid, atheruramine () bearing an ether bridge linking, one hydrobenzoin derivative, tricalydioloside () and two ursane-type triterpenes, atherurosides (A and B) ( and ) were isolated from the leaves of , together with eight known compounds. The structures of these new compounds were elucidated on the basis of the results of spectroscopic analysis, and the relative configurations of compounds were established by NOE difference. Four of the metabolites were screened against both chloroquine (CQ)-sensitive (3D7) and -resistant (Dd2) strains of ; they were found to exhibit moderate activity against chloroquine-resistant (Dd2) (IC 64.

In Vitro and In Silico Potential Inhibitory Effects of New Biflavonoids from on HIV-1 Integrase and .

The aim of this study was to identify bioactive secondary metabolites from with potential inhibitory effects against HIV and phytochemical study of root barks resulted in the identification of three new biflavonoids (-), along with four known ones (-). Compound (Gerontoisoflavone A) was a single flavonoid present in the rootbark of the plant and was used as a reference. Compound (IC = 0.

A New Triterpenoid Saponin from Albizia zygia Induced Apoptosis by Reduction of Mitochondrial Potential Status in Malignant Melanoma Cells.

In our ongoing research program on the proapoptotic function of saponins, two previously undescribed saponins, named zygiaosides E (1: ) and F (2: ), were isolated from the leaves of . Their structures were established based on extensive analysis of 1D and 2D NMR data, HR-ESI-MS analysis, and by chemical degradation. The proapoptotic effect of zygiaoside E (1: ) was evaluated on human malignant melanoma (A375), human epidermoid cancer (A431), and normal Homo sapiens skin tissue (TE 353.

Antibacterial and cytotoxic activities of undescribed cassiaric acid and other constituents from stem barks.

A new lupane-type triterpene, 2,3-dihydroxylupan-29-oic acid (), and one new ceramide derivative: (2,2',3,4,57',11,12',20)--[2'-hydroxyoctadeca-6,11-dienoyl]-2-aminohexacosa-11,20-diene-1,3,4,5-tetrol () were isolated from the ethyl acetate fraction obtained from the methanol extract of the stem barks of together with seven known compounds. Their structures were characterized using two-dimensional NMR, mass spectrometry, and compared with reported data. To date, this is the first report of the isolation of a multiple double bonds sphingolipid type from this genus.

Triterpenoid saponins and others glycosides from the stem barks of Pancovia turbinata Radlk.

In our continuing search of saponins from the plant of Sapindaceae family, phytochemical investigation of the stem barks of Pancovia turbinata Radlk., led to the isolation and structural characterization of two new triterpenoid saponins, named turbinatosides A-B (1-2), one new farnesyl glycoside, named turbinoside A (3), one new coumarin glucoside, named panturboside A (4), together with a known saponin (5). The structures of the new compounds were established, using extensive analysis of NMR techniques, mainly 1D NMR (H, C, and DEPT) and 2D NMR (COSY, NOESY, HSQC, HSQC-TOCSY and HMBC) experiments, HRESIMS and by comparison with the literature data, as 3-O-β-d-xylopyranosyl-(1 → 3)-α-l-arabinopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosylhederagenin 28-O-β-d-glucopyranosyl ester (1), 3-O-α-l-arabinopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosylhederagenin 28-O-β-d-xylopyranosyl-(1 → 4)-β-d-glucopyranosyl ester (2), 1-O-{β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranosyl}-(2E,6E)-farnes-1,12-diol (3), and 5-O-β-d-glucopyranosyl-5,6,7-trihydroxy-8-methoxycoumarin (4), respectively.

Glycosides of polygalacic acid from the stem barks of Piper guineense Schum and Thonn.

In a continuation of our study on constituents of P. guineense now focusing on the search for saponins, phytochemical investigation of the n-BuOH fraction of P. guineense stem bark led to the isolation of three previously undescribed triterpenoid saponins, named guineenosides A─C (1─3).

Antiplasmodial activities of indole alkaloids from Tabernaemontana penduliflora K. Schum (Apocynaceae).

Five undescribed carboxy-indole alkaloids with corynanthe skeleton, penduflorines A-E (1-3) as well as a voacangine-N-oxide alkaloid, tabernaemontine (4), were isolated along with eight other known compounds (5-12) from the trunk bark of Tabernaemontana penduliflora K. Schum (Apocynaceae). Their structures were determined by means of spectroscopic and spectrometric methods such as UV, IR, NMR and HR-ESI-MS.

Experimental and computational studies of an antiplasmodial derivative of allantoin; antimycobacterial essential oil from Cordia batesii WERNHAM (Boraginaceae).

Background: Chemical and pharmacological investigations were performed on the stems of Cordia batesii (Boraginaeae); chemical studies included quantum calculations applied on a newly described compound.

Results: A new derivative of allantoin (1) named batesiin (2) was characterized. Thirteen other known compounds involving allantoin (1) were either isolated or identified.

Antiplasmodial and antileishmanial inhibitory activity of triterpenes and steroidal alkaloid from the leaves of Funtumia elastica (Preuss) Stapf (Apocynaceae).

The phytochemical study of leaves of Funtumia elastica led to the isolation of three undescribed ursane derivatives, funtumic acids A, B and C (1-3), as well as one steroidal alkaloid, elasticine (4) and five other known compounds (5-9). Their structures were elucidated on the basis of NMR, MS, IR, UV spectroscopic data as well as by comparison with the literature. The compound 5-hydroxypyridine-3-carboxamide (9) was isolated for the first time from the Apocynaceae family.

Antimicrobial and cytotoxic activities of indole alkaloids and other constituents from the stem barks of Sond (Apocynaceae).

Twenty indole alkaloids, among which two undescribed ones named rauvolfianoids A () and B (), were isolated from the stem barks of Sond along with eight other compounds from other biosynthetic pathways. The structures were elucidated by analysis of spectroscopic data, including 1 D and 2 D NMR; absolute configurations of and were determined by CD exciton chirality method. Compounds and were evaluated for antimicrobial and anticancer activities against three bacterial strains (, and ) and CRC-related opportunistic pathogens.

New triterpenoid saponin from the stems of (Schumach.) W.Wight.

As part of our continuing study of apoptosis-inducing saponins from Cameroonian genus, one new triterpenoid saponin, named adianthifolioside J (), together with the known gummiferaoside E (), were isolated from stems. The structure of the new saponin (), was established on the basis of extensive analysis of 1 D and 2 D NMR (H-, C-NMR, DEPT, COSY, TOCSY, NOESY, HSQC, HSQC-TOCSY and HMBC) and HRESIMS experiments, and by chemical evidence as 3--[-D-xylopyranosyl-(1→2)--D-fucopyranosyl-(1→6)--D-glucopyranosyl]-21--{(2E,6S)-2-(hydroxymethyl)-6-methyl-6--{4--[(2E,6S)-2,6-dimethyl-6--(-D-quinovopyranosyl)octa-2,7-dienoyl]-(-D-quinovopyranosyl)octa-2,7-dienoyl]}acacic acid-28---D-glucopyranosyl-(1→3)-[5--acetyl--L-arabinofuranosyl-(1→4)]--L-rhamnopyranosyl-(1→2)--D-glucopyranosyl ester ( The pro-apoptotic activity of the new isolated saponin was evaluated, using Annexin V-FITC binding assay, on the A431 human epidermoid cancer cell. The result showed that adianthifolioside J () displayed weak pro-apoptotic activity.

Farnesyl glycosides and one new triterpenoid saponin from the roots of Lecaniodiscus cupanioides Planch. ex Benth.

Chemical investigation of the methanol extract of the roots of Lecaniodiscus cupanioides led to the isolation and characterisation of three new sesquiterpene glycosides, named cupanioidesosides A (1), B (2) and C (3), together with one new triterpenoid saponin named lecanioside A (4), Their structures were established by extensive analysis of spectroscopic methods including 1D and 2D NMR techniques (COSY, NOESY, TOCSY, HSQC, and HMBC) and HRESIMS. The four new compounds were evaluated for their antiproliferative activity against the Caco-2 cell line (human epithelial cell line). None of the isolated compounds showed positive activity in our assay.

Antileishmanial activity of long chain alkyl benzene and other constituents from seeds of L (Pedaliaceae).

The methanolic extract of the waste seeds of L. (Pedaliaceae) was subjected to chromatographic fractionation; it led to the isolation of an alkyl benzene identified as 1,3-bis (pentadecyl)benzene () along with three known fatty acids: oleic acid (), linoleic acid (), and palmitic acid (); one monosaturated cardanol, 3-pentadecylphenol () and two phytosteroids identified as sitostanol () and campestanol (). The structures of these compounds were elucidated by chemical and spectroscopic analyses.

Triterpenoid saponins from Calliandra calothyrsus Meisn. and their antiproliferative activity against two digestive carcinoma human cell lines.

The chemical investigation of the flowers and twigs of Calliandra calothyrsus (Fabaceae) led to the isolation of three new oleanane-type triterpenoid saponins, named calothyrsusosides AC (13). Their structures were established by direct interpretation of their spectral data, mainly HRESIMS, 1D NMR and 2D NMR (H, H NMR DOSY, C NMR, COSY, HSQC, HMBC, HSQC-TOCSY and NOESY) and by comparison with literature data. Compounds 1 and 2 were tested for their antiproliferative activity against two digestive carcinoma human cell lines: Hep3B (hepatocellular carcinoma) and Caco-2 (epithelial colorectal adenocarcinoma).

Chemical constituents of the leaves of (Leguminosae).

The present study deals with the isolation and the characterization of the chemical constituents from the leaves of (Leguminosae). Using various chromatographic techniques (TLC, CC, HPLC), the methanolic extract of the leaves of yielded one new alkaloid () as well as six known compounds amongst which an alkane (), isolated for the first time from a natural product, an ester of fatty acid (), two isocoumarines (), a sterol () and a disaccharide (). Their structures were elucidated using spectroscopic technics including extensive 1-D and 2-D NMR, HR-SM experiments.

Synthesis and Biological Evaluation of Four New Ricinoleic Acid-Derived 1--alkylglycerols.

A series of novel substituted 1--alkylglycerols (AKGs) containing methoxy (), -difluoro (), azide () and hydroxy () group at 12 position in the alkyl chain were synthesized from commercially available ricinoleic acid (). The structures of these new synthesized AKGs were established by NMR experiments as well as from the HRMS and elementary analysis data. The antimicrobial activities of the studied AKGs - were evaluated, respectively, and all compounds exhibited antimicrobial activity to different extents alone and also when combined with some commonly used antibiotics (gentamicin, tetracycline, ciprofloxacin and ampicillin).

Contortamide, a new anti-colon cancer cerebroside and other constituents from Stapf (Apocynaceae).

A new cerebroside, Contortamide () together with nine known compounds spegatrine (), affinisine (), Nb-methylaffinisine (), ursolic acid (), α-amyrin (), bauerenol acetate (), lupeol (), betulinic acid () and β-sitosterolglycoside () were isolated from the trunk bark of Stapf. The new compound showed significant activity against Caco-2 colon cancer cells with the MTT method. Compounds and were isolated for the first time from this species.

Antitubercular evaluation of root extract and isolated phytochemicals from Lophira lanceolata against two resistant strains of Mycobacterium tuberculosis.

Context: The roots of Lophira lanceolata Van Tiegh. Ex Keay (Ochnaceae) have numerous medicinal values in the Central African region. Even though the MeOH extract of the roots has shown antimycobacterial activities, the constituents responsible for this inhibitory activity remain unknown.

Pro-apoptotic activity of new triterpenoid saponins from the roots of Albizia adianthifolia (Schumach.) W.Wight.

As part of our study of the proapoptotic function of saponins from Cameroonian's Albizia genus, phytochemical investigation of the roots of Albizia adianthifolia led to the isolation of three new triterpenoid saponins, named adianthifoliosides GI (13). Their structures were established on the basis of extensive analysis of 1D and 2D NMR (H-, C NMR, DEPT, COSY, TOCSY, NOESY, HSQC, HSQC-TOCSY and HMBC) and HRESIMS experiments, and by chemical evidence as 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-(β-D-quinovopyranosyl)octa-2,7-dienoyl]}acacic acid-28-O-β-d-xylopyranosyl-(1 → 3)-[5-O-acetyl-α-L-arabinofuranosyl-(1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (1), 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-(β-D-quinovopyranosyl)octa-2,7-dienoyl]}acacic acid 28-O-β-d-xylopyranosyl-(1 → 3)-[α-L-arabinofuranosyl-1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (2), and 3-O-[β-d-glucopyranosyl-(1 → 2)-β-D-fucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-21-O-{(2E,6S)-2-(hydroxymethyl)-6-methyl-6-O-{4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-4-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl)octa-2,7-dienoyl]-β-D-quinovopyranosyl}-2,6-dimethylocta-2,7-dienoyl}acacic acid 28-O-β-d-xylopyranosyl-(1 → 3)-[α-L-arabinofuranosyl-1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl ester (3). The apoptotic effect of saponins 1-3 was evaluated on the A431 human epidermoid cancer cell.

Carbazole-, Aspidofractinine-, and Aspidocarpamine-Type Alkaloids from Pleiocarpa pycnantha.

Three new alkaloids, janetinine (1a), pleiokomenine A (2), and huncaniterine B (3a), and 13 known compounds, pleiomutinine (3b), huncaniterine A (3c), 1-carbomethoxy-β-carboline (4), evoxanthine (5), deformyltalbotine acid lactone (6), pleiocarpamine (7), N-methyl-10-hydroxygeissoschizol (8), spegatrine (9), neosarpagine (10), aspidofractinine (11), N-methylkopsinin (12), pleiocarpine (13), and N-methylkopsinin- N-oxide (14), were isolated from the stem bark of Pleiocarpa pycnantha. Janetinine (1a) is a carbazole alkaloid; in pleiokomenine A (2), two aspidofractinine-type alkaloids are bridged by a methylene unit in an unprecedented way, and huncaniterine B (3a) is a pleiocarpamine-aspidofractinine-type dimer. The structures and relative configurations of these compounds were elucidated on the basis of NMR and MS analyses.

Structural determination of two new acacic acid-type saponins from the stem barks of Albizia zygia (DC.) J. F. Macbr.

As a continuation of our interest in the study of triterpenoid saponins from Albizia zygia, phytochemical investigation of its stem barks led to the isolation of two new oleanane-type saponins, named zygiaosides C-D (1-2). Their structures were established on the basis of extensive analysis of 1D and 2D NMR (1H-, 13C NMR, DEPT, COSY, TOCSY, ROESY, HSQC and HMBC) experiments, HRESIMS studies, and by chemical evidence as, 3-O-[ β-d-glucopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→6)]-β-d-glucopyranosyl]-21-O-[(2E,6S)-2,6-dimethyl-6-O-(β-d-quinovopyranosyl) octa-2,7-dienoyl]acacic acid 28-O-α-l-arabinofuranosyl-(1→4)-[β-d-glucopyranosyl-(1→3)]-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl ester (1) and 3- O-[β-d-glucopyranosyl-(1→2) -[ β-d-fucopyranosyl-(1→6)]-β-d-glucopyranosyl]-21-O-[(2E,6S)-2,6-dimethyl-6-O-(β-D-quinovopyranosyl) octa-2,7-dienoyl]acacic acid 28-O-α-l-arabinofuranosyl-(1→4)-[β-d-glucopyranosyl-(1→3)]-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl ester (2).