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Although leishmaniasis has been studied for over a century, the fight against cutaneous, mucocutaneous and visceral forms of the disease remains a hot topic. This review refers to the parasitic cell wall and more particularly to the constitutive glycoconjugates. The structures of the main glycolipids and glycoproteins, which are species-dependent, are described. The focus is on the disturbance of the lipid membrane by existing drugs and possible new ones, in order to develop future therapeutic agents.

A stereospecific synthesis of trifluoromethylated codlemone is described. The key step is the treatment of 1,1-difluoro-1,4-dien-3-ol by DAST to give the corresponding (E,E)-1,1,1-trifluoro-2,4-dienic compound.

a stereospecific synthesis of (Z,E)-9,11,13-tetradecatrien-1-yl acetate and aldehyde is described. The key steps are two sequential palladium-catalyzed cross-coupling reactions between adequate organo-zinc reagents and 1,2-dibromo ethylene with stereoselective semi-hydrogenation of a dienynic intermediate.

A one-pot stereospecific synthesis of 1,5-dien-3-ynes (Z) or (E) is described, based upon a palladium-catalyzed cross-coupling reaction between butenynylzinc bromide, generated in situ from 1,1-difluoroethylene, and an adequate iodoalkene. These dienynes are converted into the corresponding trienic compounds by (Z) semi-hydrogenation.

Fluorinated analogs of the two geometrical isomers of the red bollworm moth sex pheromone were synthetized by palladium-catalyzed cross coupling reactions.

A highly regio- and stereo-selective introduction of a difluoromethylene group in allylic position is described. The key step is the treatment of 3-acetoxy-1,1-difluoro-1-propenes with Grignard reagents in the presence of copper and lithium salts.

The synthesis of a substituted mannopyranose-based amidine is described and its potential as glycosidase inhibitor evaluated. This new aminosugar derivative acts as a potent glycosidase inhibitor by virtue of its charge and shape similarities to the mannopyranosyl cation. The benzyl group of this pseudodisaccharide may also contribute to enzyme transition-state interactions.

A general C 2 vinylic homologation from carbonyl compounds (aldehydes or ketones) which leads to various α,β-insaturated acids, esters and amides, is described.

High regio- and stereo-selective introduction of a trifluoromethyl group in various unsaturatedsystems is described. The key step is the treatment of 1,1-difluoro-1-alken-3-olswith (diethylamino)sulphur trifluoride (DAST) to give 1,1,1-trifluoro-2-alkenes.

A highly regio- and stereo-selective method for the introduction of a bromo- (or chloro-) difluoromethylene group into various unsaturated systems is described. The key step is the treatment of 1,1-difluoro-1-alken-3-ols with thionyl bromide or chloride.

The reduction of 1,1-difluoro-1-alken-3-ols with lithium tetrahydroaluminate is described. 1-Fluoro-1-alken-3-ols obtained can be transformed to enals or difluoromethylated allylic derivatives.

A highly regio- and stereo-selective method for the introduction of a bromo- (or chloro-) difluoromethylene group into various unsaturated systems is described. The key step is the treatment of 1,1-difluoro-1-alken-3-ols with thionyl bromide (or chloride).

A new method for the synthesis of various 1,1-difluoroolefins is described. The key step is the treatment of 1-bromo-1,1-difluoro-2-alkenes with organo-metallic reagents in the presence of copper and lithium salts.

The four stereoisomers of 1-aminocyclopentane-1,3,4-tricarboxylic acid {ACPT-I (18) and -II (19), (3R, 4R)-III [(-)-20], and (3S,4S)-III [(+)-20]} have been synthesized and evaluated for their effects at glutamate receptors subtypes. ACPTs are ACPD analogues in which a third carboxylic group has been added at position 4 in the cyclopentane ring. None of the ACPT isomers showed a significant effect on ionotropic NMDA, KA, and AMPA receptors. On the other hand, ACPT-II (19) was found to be a general competitive antagonist for metabotropic receptors (mGluRs) and exhibited a similar affinity for mGluR1a (KB = 115 +/- 2 microM), mGluR2 (KB = 88 +/- 21 microM), and mGluR4a (KB = 77 +/- 9 microM), the representative members of group I, II and III mGluRs, respectively. Two other isomers, ACPT-I (18) and (+)-(3S,4S)-ACPT-III [(+)-20], were potent agonists at the group III receptor mGluR4a (EC50 = 7.2 +/- 2.3 and 8.8 +/- 3.2 microM) and competitive antagonists with low affinity for mGluR1a and mGluR2 (KB > 300 microM). Finally, (-)-(3R,4R)-ACPT-III [(-)-20] was a competitive antagonist with poor but significant affinity for mGluR4a (KB = 220 microM). These results demonstrate that the addition of a third carboxylic group to ACPD can change its activity (from agonist to antagonist) and either increase or decrease its selectivity and/or affinity for the various mGluR subtypes.

The treatment of 1-bromo-1,1-difluoro-2-alkenes with organometallic reagents in the presence of copper and lithium salts leads to 1,1-difluoroolefins.

A one pot synthesis of α-trifluoromethyl unsaturated acids and derivatives via a [3,3]-sigmatropic rearrangement of allyl (or propargyl) fluorovinyl ethers is described.

A one pot synthesis of α-trifluoromethyl unsaturated acids via a [3,3]-sigmatropic rearrangement of allyl (or propargyl) fluorovinyl ethers is described. By proto- and iodolactonization, these acids lead to the corresponding trifluoromethylated lactones.

This paper presents the crystal structure and the phase transitions of K x Na 1− x NbO 3 (0.4 ≤ x ≤ 0.6). X-ray diffraction measurements were used to follow the change of the unit-cell parameters and the symmetry in the temperature range 100–800 K. At room temperature all the compositions exhibited a monoclinic metric of the unit cell with a small monoclinic distortion (90.32° ≤ β ≤ 90.34°). No major change of symmetry was evidenced in the investigated compositional range, which should be characteristic of the morphotropic phase-boundary region. With increasing temperature, the samples underwent first-order monoclinic–tetragonal and tetragonal–cubic transitions. Only the potassium-rich phases were rhombohedral at 100 K.

The crystal structure of the 1 + 2 mixed-layer Aurivillius phase Bi5Ti1.5W1.5O15 (SG I2cm no 46: − c b a , Z = 4 , a = 5.4092 ( 3 ) A , b = 5.3843 ( 3 ) A and c = 41.529 ( 3 ) A ) consisting of the ordered intergrowth of one and two octahedra thick perovskite-type blocks separated by [Bi2O2]2+ slabs is reported. Supported by an electron diffraction investigation and, using the Rietveld analysis, it is shown that this compound should be described using a I-centering lattice in agreement with the generalised structural model of the Aurivillius type compounds recently presented by the authors. The structure of this Bi5Ti1.5W1.5O15 phase is analyzed in comparison with the related simple members (Bi2WO6 and Bi3Ti1.5W0.5O9). The crystal structure of Bi3Ti1.5W0.5O9 is also reported.

The synthesis of carbasugars and various aminocyclitols, related to voglibose and acarbose used in the treatment of non-insulino-dependant diabetes, is described from C 2 -symmetrical bis-epoxides derived from d -mannitol. The methodology involves two key steps: a domino alkylation–cyclization with 2-lithio-1,3-dithiane derivatives, and reduction or reductive amination with a primary amine. These compounds have been evaluated as inhibitors of several glycosidases, and this study indicates notably that the l - ido or d - manno 1-aminocycloheptane-3,4,5,6-tetrol are inhibitors of α- d -glucosidase with K i in the micromolar range.

A one-pot synthesis of α-bromo β-substituted γ-unsaturated acids via a diastereoselective Claisen rearrangement of allyl bromofluorovinyl ethers is described.

A simple stereospecific synthesis of (E)-11, 13-hexadecenyn-1-yl acetate, alcohol and aldehyde is described, based upon hydroalumination of a ω -terbutoxy alkyne, followed by palladium-catalysed cross coupling reaction.

A convenient preparation of (Z, E) 9, 11-and (Z, Z) 9, 11-tetradecadien-1-yl and (9Z) 9, 11-tetradecenyn-1-yl acetate, alcohol and aldehyde with 99.5 % stereoisomeric purity is described. The key step of this synthesis is the carbocupration of acetylene followed by palladium catalyzed cross coupling reaction with the appropriate zinc reagent.