Synthesis of imidazo[1,2-a]pyridine derivatives as antiviral agents.

The synthesis and antiviral activity of original dibromoimidazo[1,2-a]pyridines bearing a thioether side chain are reported. Molecular modeling was used to identify biophoric structural patterns that are common to 16 compounds. Structure-activity relationship (SAR) studies identified hydrophobicity (logP) as the most important factor for activity. From these SAR studies, the antiviral activity could be predicted.

Reactivity of 3-iodoimidazo[1,2-a]pyridines using a Suzuki-type cross-coupling reaction.

The influence of base and solvent in Suzuki cross-coupling reaction on various 2-substituted-3-iodoimidazo[1,2-a]pyridines was reported. The reactivity was largely influenced by nature of the substituent. Optimized yields and shortened times of reaction were obtained using strong bases in DME.

Synthesis of diaryl-substituted imidazo[l,2-a]pyridines designed as potential aromatase inhibitors.

From a pharmacophore model of bicyclic heterocycles as aromatase inhibitors we have designed three series of imidazo[1,2-a]pyridine derivatives. The synthesis and the spectroscopy determination of various compounds are reported. The crystal data of one of these compounds (10b) was obtained. The aromatase inhibition potency was evaluated in vitro and no activity was found.

Differing substomatal and chloroplastic CO2 concentrations in water-stressed wheat.

Gas exchanges of wheat (Triticum aestivum L. cv. Courtot) shoots were measured before and during a water stress. While photosynthesis, transpiration and dark respiration decreased because of the stress, photorespiration increased initially, up to a maximum of 50% above its initial value. The CO2 concentration in the intercellular space was calculated from gas-diffusion resistances, and remained approximately constant before and during the stress. On the other hand, the CO2 concentration in the chloroplast, in the vicinity of Ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco), was evaluated from the ratio of CO2 to O2 uptake, using the known kinetic constants of the oxygenation and carboxylation reactions which compete for Rubisco. In the well-watered plants, the calculated chloroplastic concentration was slightly smaller than the substomatal concentration. During water stress, this concentration decreased while the substomatal CO2 concentration remained constant. Hypotheses to explain this difference between substomatal and chloroplastic CO2 concentrations are discussed.

The C23A: first step to a monitoring system of CELSS in flight.

Studies for every level of CELSS: Waste processing, food production, photosynthesis system, and so on ..., imply an automatic system to control, command and quantify gases, water and chemical compounds. Used for many years in plant physiology studies, the C23A system monitors the analysis and quantifies gases (O2, CO2. N2, ...), physical parameters (temperature, humidity, ...) and chemical compounds (NH4+, N03-, ...) on numerous experiments. In the new version, the architecture of the computing system is near of the space requirements. We have chosen a structure with three independent levels: acquisition, monitoring and supervision. Moreover, we use multiplexed analysers: IRGA, mass spectrometer and cheminal analyser. The multiplexing increases the accuracy of the measurements and could facilitate the spatialization. Thus the whole structure anticipates the entire separation between automation in space and control-command on ground.