Relationships between key functional traits of the waterlily and wetland nutrient content.

Little attention has been paid to how aquatic habitat characteristics affect the traits of plant species. (L.) Sm.

Occurrence and ecological determinants of the contamination of floodplain wetlands with Klebsiella pneumoniae and pathogenic or antibiotic-resistant Escherichia coli.

The survival and multiplication of human pathogenic and antibiotic-resistant bacteria in ecosystems is of increasing concern but has been little explored. Wetlands can be contaminated by water fluxes from rivers and may present environmental conditions leading to bacterial survival and multiplication. To test this hypothesis, we sampled 16 wetlands located along three rivers of the Jura Massif, France.

Photolysis and thermolysis of platinum(IV) 2,2'-bipyridine complexes lead to identical platinum(II)-DNA adducts.

Two Pt(IV) and two Pt(II) complexes containing a 2,2'-bipyridine ligand were treated with a short DNA oligonucleotide under light irradiation at 37°C or in the dark at 37 and 50°C. Photolysis and thermolysis of the Pt(IV) complexes led to spontaneous reduction of the Pt(IV) to the corresponding Pt(II) complexes and to binding of Pt(II) 2,2'-bipyridine complexes to N7 of guanine. When the reduction product was [Pt(bpy)Cl(2)], formation of bis-oligonucleotide adducts was observed, whereas [Pt(bpy)(MeNH(2))Cl](+) gave monoadducts, with chloride ligands substituted in both cases.

Trioxaquines and heme-artemisinin adducts inhibit the in vitro formation of hemozoin better than chloroquine.

Trioxaquines, potential antimalarial agents, and heme-artemisinin adducts, resulting from the alkylation of heme by artemisinin, were evaluated as inhibitors of beta-hematin formation in 10 M acetate medium at pH 5.

Trioxaquines are new antimalarial agents active on all erythrocytic forms, including gametocytes.

Malaria is the third most significant cause of infectious disease in the world. The search for new antimalarial chemotherapy has become increasingly urgent due to parasite resistance to classical drugs. Trioxaquines are synthetic hybrid molecules containing a trioxane motif (which is responsible for the antimalarial activity of artemisinin) linked to an aminoquinoline entity (which is responsible for the antiplasmodial properties of chloroquine).

Synthesis of new macrocyclic chiral manganese(III) Schiff bases as catalysts for asymmetric epoxidation.

We describe a general synthetic strategy for the preparation of a series of macrocyclic chiral manganese(III) salen complexes. The developed reaction pathway allows the modulation of the different key groups, namely, the chiral diimine, the bulky substituents in positions 3 and 3', and the linker used in the macrocyclization of the Schiff base. The different complexes presented here illustrate these readily available structural variations.

Heme alkylation by artesunic acid and trioxaquine DU1301, two antimalarial trioxanes.

The sesquiterpene Artemisinin, an antimalarial drug that is effective against multidrug-resistant Plasmodium falciparum strains, contains a 1,2,4-trioxane, and the endoperoxide function plays a key role in its biological activity. However, its poor solubility means that hemisynthetic derivatives, such as artesunic acid, are preferred for drugs. The reductive activation of the peroxide function of artemisinin by iron(II)-heme produces heme derivatives that are alkylated at meso positions by a C-centered radical derived from artemisinin.

Synthesis and antimalarial activity of trioxaquine derivatives.

Trioxaquines are dual molecules that contain a trioxane motif linked to an aminoquinoline entity. Among the different compounds of this series, trioxaquine cis-15 (DU1302 c), prepared from alpha-terpinene, a cheap natural product, showed efficient antimalarial activity in vitro on both sensitive and resistant strains of Plasmodium falciparum (IC(50)=5-19 nM). A stereochemical description of this stable, nontoxic, and non-genotoxic antimalarial agent is detailed.