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A chemical investigation of the aerial parts of Bupleurum montanum (Coss. & Dur.) (Apiaceae) afforded five compounds, quercitin 1, tamarexetin 2, isorhamnetin-3-rutinoside 3, kaempferol-3-O-β-rutinoside 4, and 3,4-dihydroxybenzoic acid (Protocatechuic acid) 5. The structural elucidation was performed mainly by MS, 1D and 2D NMR spectrum data.

Two new friedelane-type triterpenes named 12alpha-hydroxyfriedelane-3,15-dione and 3beta-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.

Condensation of either 2-bromobenzoic acid (4) or 2-chloro-3-nitrobenzoic acid (5) with suitable aminoquinolines 6-8 afforded phenylquinolylamines 9-13. Acid mediated cyclization gave the corresponding 12H-benzo[b][1,7]phenanthrolin-7-ones 14 and 15, and 12H-benzo[b][1,10]phenanthrolin-7-ones 16-18. Compounds 14, 16, and 17 were subsequently N-methylated to 6-demethoxyacronycine and acronycine analogues 19-21, whereas reduction of the aromatic nitro group of 18 gave the amino derivative 22. Unsubstituted 12H-benzo[b][1,10]phenanthrolin-7-ones 16, 17, 20, and 21 were devoid of significant cytotoxic activity, whereas 18 and 22, bearing a nitrogen substituent at position 11, were significantly active. Unsubstituted 12H-benzo[b][1,7]phenanthrolin-7-ones 14 and 19, which include a pyridine nitrogen in the same 4-position as the pyran oxygen of acronycine exhibited cytotoxic activities within the same range of magnitude as acronycine itself.

Vitex madiensis Oliv. (Lamiaceae) is traditionally used to treat malaria symptoms in Haut-Ogooue, Gabon. Leaves and stem barks extracts were obtained using dichloromethane (CH(2)Cl(2)), ethyl acetate (EtOAc) and methanol (MeOH) as extraction solvents and fractionated on silica gel column. The in vitro antiplasmodial activity of CH(2)Cl(2), EtOAc and MeOH extracts and fractions was evaluated against the chloroquine-resistant FCB strain and field isolates of Plasmodium falciparum using the DELI test. The cytotoxicity of the extracts was tested on MRC-5 and THP1 cells using the tetrazolium salt MTT colorimetric assay, and the selectivity index (SI) of each extract was calculated. CH(2)Cl(2) extract, the EA1 fraction from EtOAc extract of stem barks and cyclohexane (L(cycl)), dichloromethane (L(DM)) and butanol (L(but)) fractions from MeOH/H(2)O extract of leaves exhibited the highest in vitro antiplasmodial activity on FCB strain and field isolates (IC(50) from 0.53 to 4.87 μg/ml) with high selectivity index (of 20.15-1800). These data support the use of V. madiensis in malaria treatment along with continued investigations within traditional medicines in the search of new antimalarial agents. The EA1, C(6)H(12) and CH(2)Cl(2) fractions could be selected for future investigation or/and for the treatment of malaria symptoms after standardization.

International audience; Quinas contains several compounds, such as quinoline alkaloids, principally quinine, quinidine, cinchonine and cichonidine. Identified from barks of Cinchona, quinine is still commonly used to treat human malaria. Microwave-Integrated Extraction and Leaching (MIEL) is proposed for the extraction of quinoline alkaloids from bark of Cinchona succirubra. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. Optimal conditions for extraction were obtained using a response surface methodology reached from a central composite design. The MIEL extraction has been compared with a conventional technique soxhlet extraction. The extracts of quinoline alkaloids from C. succirubra obtained by these two different methods were compared by HPLC. The extracts obtained by MIEL in 32 min were quantitatively (yield) and qualitatively (quinine, quinidine, cinchonine, cinchonidine) similar to those obtained by conventional Soxhlet extraction in 3 hours. MIEL is a green technology that serves as a good alternative for the extraction of Cinchona alkaloids.

International audience; Two new dimethylpyrano-isoflavones, named erymildbraedin A (4) and B (5), were isolated from the stem bark of the Cameroonian medicinal plant Erythrina mildbraedii, along with four known ones, the linear congeners, scandenone (1), erysenegalinsein M (2), 5,4'-dihydroxy-2'-methoxy-8-(3,3-dimethylallyl)-2'',2''-dimethylpyrano[5,6:6,7]isoflavone (3), and the angular isoflavone eryvarin B (6), and two other compounds, fraxidin and scoparone. Their structures were elucidated by the usual spectroscopic methods and isoflavone effects on the growth of human breast, prostate, and endometrial adenocarcinoma cells were determined. Isoflavones 1, 3, and 6 strongly inhibited the growth of all three cell lines, supporting the notion that a non-oxidized isoprenyl group at C-8 is requisite for cytotoxic activity.

The stereoselective synthesis of hordenine β-L-rhamnopyranoside (3) was achieved using 4-O-acetyl-2,3-O-carbonyl-α-L-rhamnopyranosyl bromide (14) as key intermediate. The regiospecific syntheses of the peracetyl derivatives of (E)-O-(6-O-cinnamoyl-β-D-glucopyranosyl)-(1 → 2)-, (1 → 3)-, and (1 → 4)-α-L-rhamnopyranoses and of their 4-acetoxycinnamoyl counterparts were achieved through the use of various types of rhamnose-derived intermediates, i.e., 1,2-O-orthoester for the (1 → 2) series, 2,3-O-orthoester for the (1 → 3) series, and 2,3-O-isopropylidene for the (1 → 4) series.

The MeOH extract of the stem barks of Drypetes tessmanniana (Euphorbiaceae) afforded two new triterpene derivatives characterized as 3beta-O-(E)-3,5-dihydroxycinnamoyl-11-oxo-olean-12-ene and 3beta,6alpha-dihydroxylup-20(29)-ene together with seven known compounds. Their structures were established on the basis of spectral analysis.

Sarcodifurines A and B are two original dihydrofuroquinolines isolated from Sarcomelicope follicularis, a New Caledonian tree. The cytotoxicity and antiproliferative activity of these two alkaloids were investigated against 8 distinct cell lines representative of the most frequent solid tumors developing in human. Cytotoxicity of sarcodifurines was low on the 8 cell lines, with, for example, less than 10% of the total cells killed after 24 h exposure at 10 microM and IC(50) approximately 7.10(-5) M (MCF-7 and MDA MB 231 cell lines). Proliferation studies confirmed that sarcodifurines had a weak effect on cancer cells growth, with less than 5% growth inhibition at 10 microM. Sarcodifurine A activity was comparable to that of Sarcodifurine B, in term of cytotoxicity and antiproliferative activity on all cell lines. In spite of the weak activity of sarcodifurines and furoquinolines, rationalized pharmacomodulations to obtain planar analogs could lead to efficient topoisomerases inhibitors and DNA intercalants.

Condensation of 2-chloro-3-nitrobenzoic acid with either 5-amino-7-methoxy-2,2-dimethyl-2H-chromene or 5-amino-2,2-dimethyl-2H-chromene afforded diphenylamines 14 and 15. Trifluoroacetic anhydride mediated cyclization gave the corresponding acridones 16 and 17, which were subsequently N-methylated and reduced to 11-aminoacronycine and 11-amino-6-demethoxyacronycine. These two amino compounds, which gave stable water soluble salts, were 2- to 3-fold more potent than acronycine or 6-demethoxyacronycine in inhibiting L1210 cell proliferation.

Condensation of 1-bromo-2-naphthalenecarboxylic acid (9) with 7-methoxy-2,2-dimethyl-2H-1-benzopyran-5-ylamine (13) followed by acid-mediated cyclization afforded 6-methoxy-3,3-dimethyl-3,14-dihydro-7H-benzo[c]pyrano[3,2-h]acridin-7-one (15), which was further methylated into 6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[c]pyrano[3,2-h]acridin-7-one (benzo[c]acronycine) (3) and 6,7-dimethoxy-3,3-dimethyl-3H-benzo[c]pyrano[3,2-h]acridine (4). Osmium tetroxide oxidation of 15 gave the (+/-)-cis-diol 16, which afforded the benzopyranoacridine and benzopyranoacridone esters 17-22 upon acylation. Condensation of 9 with suitable aminoquinolines 23-25 afforded the carboxylic naphthylquinolylamines 26-28. Cyclization gave the corresponding naphtho[1,2-b][1,10]-phenanthrolin-7(14H)-ones 29 and 30, and naphtho[1,2-b][1,7]-phenanthrolin-7(14H)-one 31, which were subsequently N-methylated to the desired 14-methylnaphtho[1,2-b][1,10] and [1,7]-phenanthrolinones 6, 7, and 8. Benzo[c]pyrano[3,2-h]acridin-7-one derivatives 3, 16, and 22 displayed cytotoxic activities within the same range of magnitude as acronycine itself, whereas 7-alkoxybenzo[c]pyrano[3,2-h]acridine and 7-acyloxybenzo[c]pyrano[3,2-h]acridine derivatives 4 and 17-21 were less active when tested against L1210 murine leukemia cells in vitro. Naphthophenanthrolinones 6-8 were devoid of significant antiproliferative activity, but compounds 29-31 bearing no substituent on the nitrogen atom at position 14 were more potent.

An actinomycete strain NM94 was isolated from a Saharan soil sample by a dilution agar plating method using chitin-vitamins B medium supplemented with penicillin. The strain presented the morphological and chemical characteristics of the genus Nonomuraea. On the basis of 16S rDNA analysis and physiological tests, this isolate was found to be quite different from the known species of Nonomuraea and might be new. The strain NM94 secreted several antibiotics on yeast extract malt extract glucose medium that were active against some Gram-positive bacteria, yeast, and fungi. The antibiotics were extracted with dichloromethane and detected by bioautography on silica gel plates using Mucor ramannianus and Bacillus subtilis as the test organisms. Among these antibiotics, a complex called 94A showed interesting antifungal activity. It was selected and purified by reverse-phase HPLC. This complex was composed of five compounds. Spectroscopic studies by infrared, mass, and 1H NMR of the compounds were carried out. Initial results showed that these molecules differed from the known antibiotics produced by other Nonomuraea species.

Hyperfoliatin, a new polyisoprenylated phloroglucinol derivative was isolated from the aerial parts of Hypericum perfoliatum (Clusiaceae) collected in Algeria. The structure of hyperfoliatin was elucidated on the basis of its spectral data, mainly MS and multiple-pulse NMR.

Three new natural dithiopyrrolone antibiotics, 3-methyl-2-butenoylpyrrothine (1), tigloylpyrrothine (2), and n-butyropyrrothine (3) were isolated along with the known iso-butyropyrrothine (4) and thiolutin (5) from the fermentation broth of Saccharothrix sp. SA 233. The structures of the novel compounds were established on the basis on their spectral data.

Three new natural antibacterial and antifungal dithiolopyrrolone antibiotics were isolated along with the known iso-butyropyrrothine and thiolutine from the fermentation broth of an actinomycete strain which was isolated from a saharian palm grove soil collected at Adrar, south Algeria. The strain was identified as Saccharothrix sp. The three new antibiotics exhibited broad antimicrobial activity against Gram-positive bacteria, yeasts and fungi in vitro.

The essential oil of aerial parts of Cachrys libanotis L. (Apiaceae) from east Algeria was extracted by hydrodistillation and analyzed by GC-FID and GC-MS. Thirty-one compounds were identified, the main components being germacrene-D (18.0%), γ-terpinene (6.4%), p-cymene (5.5%), caryophyllene oxide (5.1%), and limonene (5.1%).

Racemic 7-hydroxy-9-oxa anthracyclinone (5a) has been synthetised in seven steps from quinizarin (6) and its resolution achieved after glycosylation with 3, 4-di-O-acetyl-2-deoxy-L-fucose. Chiral pool syntheses of (8S)-8-hydroxymethyl-9-oxa-anthracyclinone (5b) and of (8S, 10R) and (8S, 10S)-8-hydroxymethyl-10-methyl-9-oxa-anthracyclinones (5c and 5d) have been achieved using (R)-2, 3-O-isopropylideneglyceraldehyde (12) and leucoquinizarin (13) as starting materials. Glycosylation of aglycones 5b-5d by either 3, 4-di-O-acetyl-2-deoxy-L-fucose or various 3-amino-2, 3, 6-trideoxy-L-hexoses yielded the corresponding anthracyclines. The synthetic glycosides do not show significant cytotoxic activity at a concentration of 1 μg/ml against L 1210 cells.