Alain Carpy

1,5-D-anhydrofructose, the precursor of the pyrone microthecin in Morchella vulgaris

Abstract The carbohydrate which, in various Discomycetes, is enzymatically converted under plasmolytic conditions to the antibiotic pyrone microthecin was isolated from a strain of Morchella vulgaris and identified as 1,5- D -anhydrofructose from X-ray analysis of its oxime.

Synthesis and evaluation of pyrazolignans. A new class of cytotoxic agents.

A series of fused pyrazole derivatives of cyclolignans have been prepared through simple chemical routes and evaluated for their cytotoxic activities in culture cells of P-388 murine leukemia, A-549 lung carcinoma and HT-29 colon carcinoma. Despite the lack of the lactone moiety in their structures, they show IC50 values at microM levels.

Synthesis and antidepressant activity of 5-(1-aryl-4-piperazino)methyl-2-amino-2-oxazolines

Abstract The synthesis of 20 5-(1-aryl-4-piperazino)methyl-2-amino-2-oxazolines is described. Antidepressant activity was observed in mice using classical screening tests. Structure-activity relationships were studied and correlated with the nature of the aromatic substituent. Preliminary lipophilic and electronic properties of one lead compound (COR 3224) have been described.

Propriétés electriques et magnétiques des bronzes oxyfluorés de vanadium de formule α′-NaV2O5−xFx (0 ⩽ x ⩽ 1)

Abstract On the basis of the crystal structures, the distribution of the d electrons on the vanadium atoms is determined in NaV2O5 and NaV2O4F as well as in the intermediate NaV2O5−xFx solid solution (0

Synthesis and QSAR Studies in 2-(N-aryl-N-aroyl)amino-4,5-dihydrothiazole Derivatives as Potential Antithrombotic Agents ☆

A series of 2-(N-aryl-N-aroyl)amino-4,5-dihydrothiazole derivatives have been synthesized via cyclocondensation of N-aryl thioureas with 2-bromoethylamine hydrobromide followed by the reaction of the product thus obtained with aroyl chlorides. Title compounds were evaluated for their antithrombotic activity in vivo in mice where one of these compound 29 provided 65% protection as compared to 77% protection offered by the standard Indomethacin. Quantitative Structure-Activity Relationship (QSAR) studies were performed on these compounds using physicochemical (hydrophobic, electronic, steric) parameter as independent and antithrombic activity as dependent parameter, where antithrombotic activity correlated best (r > 0.8) with electronic parameters (F, sigma or mu) having high statistical significance > 99.9% (F(2,22)>15.0; F(2,22alpha:0.001)=11.0) suggesting that hydrophobic, steric and resonance factors are insignificant in this set of molecules for the activity.

Theoretical study of the thermal degradation pathways of abietane skeleton diterpenoids: aromatization to retene

The results of a theoretical study concerning the thermal degradation of abietane skeleton diterpenoids which results in the fully aromatized retene product are presented. The semi-empirical AM1/UHF method has been used to elaborate all reaction pathways that could be encountered during dehydrogenation, demethylation and decarboxylation processes. The topological study of these reaction pathways allows to propose the most probable reaction mechanisms involved in the aromatization of abietic acid to retene.

Etude par microscopie electronique de quelques termes de la serie (Na, Ca)n Nbn O3n+2

Abstract A regular stacking of perovskite type blocks has been observed by electron microscopy in the (NaCa)n Nbn O3n+2 phases, with n = 4, 5 and 6. Observation of ordered intergrowth with n = 4.5 has shown an alternation of blocks of different thickness n = 4 and n = 5. An other ordered intergrowth with n = 4.33 has been observed.

Keto/enol tautomerism in phenylpyruvic acids: structure of the o-nitrophenylpyruvic acid

Abstract The synthesis of a tautomeric keto/enol mixture of o-nitrophenylpyruvic acid followed the acid hydrolysis of the azlactone of o-nitrobenzaldehyde was carried out. The structures of the two tautomeric forms were assigned by NMR spectroscopy. X-ray diffraction of a single crystal revealed that the crystalline form corresponds to the keto tautomer. Quantum mechanics calculations in the gas phase confirmed the experimental findings in solution.

Ab initio calculations of tautomer equilibrium and protonation enthalpy of 2-amino-2-oxazoline in the gas phase: basis set and correlation effects

Abstract Ab initio calculations are performed to evaluate molecular properties of the two tautomeric forms of 2-amino-2-oxazoline and the protonated form with extended basis set at Hartree–Fock, Moller–Plesset perturbation (MP2) and density functional (BLYP, B3LYP) levels. Optimized geometries, atomic charge distributions, dipole moments, energies, tautomer equilibrium constant and protonation enthalpy are carefully analysed. The results obtained at different computational levels are compared to highlight the effects of basis set and correlation.

Defects and diffusion paths in perovskite-like structures ABO3+x

Abstract A new mechanism is proposed for the formation and the migration of planar defects in ABO3+x, perovskite-type compounds.