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The composition of the essential oils of stems and seeds of Pituranthos scoparius was determined by GC-MS. Almost 50 compounds were identified. In the seed oil, the main compounds were α-pinene (8.2%), β-pinene (4.6%), p-cymene (7.5%), limonene (11.2%), thymol (5.9%), myristicin (11.1%) and dill apiole (12.2%); in the stem oil, the main compounds were α-pinene (6.8%), α-phellandrene (7.1%), limonene (9.8%), methyl eugenol (5.6%) germacrene D (12.7%), myristicin (7.2%), spathulenol (4.5%) and β-eudesmol (4.1%).

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.

Prototypes corresponding to glycopeptide fragments of actinoidin antibiotics have been synthesized using an L-acosaminyl-D-glucose-containing heterodisaccharide linked to 4-hydroxyphenylglycine as pivotal synthon. This latter compound has been obtained by coupling of a suitably protected D-glucopyranosyl bromide with the blocked amino acid, followed by selective deprotection of the glucopyranosyl moiety at C-2 and subsequent stereospecific attachment of the acosaminyl unit.

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 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.

A new iridoid glucoside dimer, coelobillardin (1), was isolated from the aerial parts of Coelospermum billardieri. Its structure has been elucidated on the basis of MS and NMR data. From a biogenetic point of view, this compound, which includes a cyclobutane basic core, should be considered as a [2+2] dimerization product of (E)-10-(4-hydroxycinnamoyloxy)loganin, which is the major iridoid isolated from the plant.

Two new friedelane-type triterpenes named 12α-hydroxyfriedelane-3,15-dione and 3β-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.

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

An efficient methodology for the preparation of a series of 2,3-disubstituted-quinazolin-4(3 H )-ones is described via a three step reaction from anthranilic acid. The obtained results also reveal that microwave-assisted rapid decomposition of formamide under controlled conditions of power, temperature and time is a very convenient source of ammonia for the synthesis of 2-substituted-quinazolin-4(3 H )-ones and other rings.

International audience; The influence of chemical neighbouring on oxidation of substituted 2,2‐dimethylchromenes derivatives 5‐8 by a biomimetic catalytic system was first studied. It was then applied to acronycine an anti‐cancer drug in order to obtain in one single step oxidized products resulting from the reactivity of the 1,2‐double bond in the pyranic D‐ring. These 2,2‐dimethylchromenes constitute the structural moiety responsible for the activity of acronycine. This oxidation showed the sensitivity of the ethylenic bond, leading to the formation of the corresponding epoxides, diols and/or ketoalcohol. In the case of 5‐dimethylamino‐2,2‐dimethylchromene 8 , the double bond was not sensitive to oxidation, but the N ‐methyl groups reacted to lead to the formamide derivative 16 and an imino‐alcohol 17 . This methodology applied to acronycine molecule 1 , allowed to obtain in one step, two oxidized compounds, a trans ‐diol 3 and a ketoalcohol 4 under preparative conditions.

Two novel furoquinolines, named sarcodifurine A (1) and B (2) were isolated from the leaves of Sarcomelicope follicularis (Rutaceae). The structures were elucidated on the basis of spectroscopical data, especially 2D-HMBCand HMQC NMR experiments. The relative configurations were unambiguously determined by single-crystal X-Ray diffraction analyses.

Partial Synthesis and Oncostatic Properties of Pseudotubulosines, Analogues of Emetine and Tubulosine Pseudotubulosines, structural analogues of emetine and tubulosine, have been synthesized by either Pictet-Spengler or Bischler-Napieralski condensation from dihydrocorynantheal or corynantheidal. Spectral data, cytotoxic and oncostatic properties of these new alkaloids are described.