Chirality Effects on Repellent Properties of 4-Alkoxycoumarins Against Asian Tiger Mosquito (Diptera: Culicidae).

The use of semiochemicals as repellents and attractants has been proposed to complement insecticides used for the control of vector mosquito populations. In several studies, the optical purities of the molecules tested have been described as having little or no effect on repellent activity. However, these observations seem difficult to explain because of the chirality effect of molecules on the olfactory system of insects and humans.

Development of Sustainable Chemistry in Madagascar: Example of the Valuation of CNSL and the Use of Chromones as an Attractant for Mosquitoes.

This article describes a part of the results obtained from the cooperation between the University of Lyon1 (France) and the University of Antananarivo (Madagascar). It shows (among others) that useful research can be carried out in developing countries of the tropics if their social, technical, and economic conditions are taken into account. The concepts and methods associated with so-called "green chemistry" are particularly appropriated for this purpose.

Effect of the Stereoselectivity of -Menthane-3,8-diol Isomers on Repulsion toward .

Vector-borne diseases cause around 700,000 deaths every year. Insect repellents are one of the strategies to limit them. -menthane-3,8-diol (PMD), a natural compound, is one of the most promising alternatives to conventional synthetic repellents.

Small-scale land-use variability affects Anopheles spp. distribution and concomitant Plasmodium infection in humans and mosquito vectors in southeastern Madagascar.

Background: Deforestation and land-use change have the potential to alter human exposure to malaria. A large percentage of Madagascar's original forest cover has been lost to slash-and-burn agriculture, and malaria is one of the top causes of mortality on the island. In this study, the influence of land-use on the distribution of Plasmodium vectors and concomitant Plasmodium infection in humans and mosquito vectors was examined in the southeastern rainforests of Madagascar.

Field evaluation of synthetic lure (3-methyl-1-butanol) when compared to non odor-baited control in capturing Anopheles mosquitoes in varying land-use sites in Madagascar.

Background: Malaria is the 4(th) largest cause of mortality in Madagascar. To better understand malaria transmission dynamics, it is crucial to map the distribution of the malaria vectors, mosquitoes belonging to the genus Anopheles. To do so, it is important to have a strong Anopheles-specific lure to ensure the maximum number of captures.

Euphane triterpenoids of Cassipourea lanceolata from the Madagascar rainforest.

Fractionation of an ethanol extract of a Madagascar collection of the leaves and fruit of Cassipourea lanceolata Tul. led to the isolation of three euphane triterpenoids 1-3. The (1)H and (13)C NMR spectra of all compounds were fully assigned using a combination of 2D NMR experiments, including COSY, TOCSY, HSQC (HMQC), HMBC and ROESY sequences.

Survival and growth of seedlings of 19 native tree and shrub species planted in degraded forest as part of a forest restoration project in Madagascar's highlands.

Percentage survival and mean percentage change in height were compared for 19 native tree and shrub species planted at Ankafobe Forest, a degraded fragment of highland forest, at ten months after planting. The species varied considerably in both, survival and growth. Best performers included Macaranga alnifolia (Euphorbiaceae), Harungana madagascariensis (Clusiaceae), Filicium decipiens (Sapindaceae) and Dodonaea madagascariensis (Sapindaceae).

Antiplasmodial activity of compounds from Sloanea rhodantha (Baker) Capuron var. rhodantha from the Madagascar rain forest.

Bioassay-directed separation of the butanol-soluble portion of an extract of Sloanea rhodantha (Baker) Capuron var. Rhodantha (Elaeocarpaceae) active against the drug-sensitive HB3 strain of Plasmodium falciparum led to the isolation of seven phenolic compounds, gallic acid (1), 3,5-di-O-galloylquinic acid (2), 1,6-di-O-galloyl glucopyranoside (3), 3,4,5-tri-O-galloylquinic acid (4), 1-O-eudesmoylquinic acid (5), 1,2,3,6-tetra-O-galloyl glucopyranoside (6), and 3,4,5-trimethoxyphenyl-(6'-O-galloyl)-O-b-D-glucopyranoside (7). The structure of the new compound 5 was established on the basis of interpretation of its 1D and 2D NMR spectroscopic data.