Tetrathiafulvalene hydrazone: efficient synthon for the synthesis of novel bidentate redox active ligands

The synthesis and the ability of TTF-hydrazone to act as a versatile precursor for the design of electroactive ligands are reported together with the chelating ability of these ligands through their M(CO)₄ complexes, (M = Mo, W).     

Deduction as Reduction, from a Categorical Point of View

Deduction systems and graph transformation systems are compared within a common categorical framework. This comparison results in a proposal for a new deduction method in diagrammatic logics, allowing the deletion of intermediate lemmas.     

Categorical (binary) difference terms and protomodularity

In this paper we obtain an intrinsic syntactical characterization of protomodularity, via so-called categorical difference terms, similar to the one known in the case of varieties involving binary terms d satisfying d(x, x) = d(y, y). We also show that purely categorical modifications of the condition in the characterization give characterizations of Mal’tsev and additive categories, thus revealing a new conceptual link between these three classes of categories, and hence, also between the corresponding classes of varieties.     

Synthesis of Protein Conjugates of 2-Carboxy-L-Arabinitol 5-Phosphate and 2-Carboxy-L-Ribitol 5-Phosphate

Abstract

The synthesis of 5-O-[5-(pentanoic acid)]-phosphono-L-erythro-pent-2-ulose 2 was successfully achieved by coupling benzyl 5-hydroxypentanoate 9b and 1-O-benzyl-L-erythro-pent-2-ulose ethane- 1,2-diyl dithioacetal 13 with the enediol pyrophosphate 18. Compound 2 was coupled to carrier proteins, porcine thyroglobuline and bovine serum albumin and the conjugates were treated with KCN to give conjugates of the hapten 1, designed to raise catalytic antibodies.     

Induced Chiroptical Changes of a Water‐Soluble Cryptophane by Encapsulation of Guest Molecules and Counterion Effects

We report the synthesis of the water‐soluble cryptophanol derivative 1 and the study of the chiroptical properties of its two enantiomers (>99 % ee) by polarimetry, electronic circular dichroism (ECD), and vibrational circular dichroism (VCD). We show that cryptophanol 1 exhibits unusual chiroptical properties in water under basic conditions (pH>12). For instance, the shapes of the ECD and VCD spectra of 1 in water were strongly dependent on the nature of the alkali metal ions (Li⁺, Na⁺, K⁺, Cs⁺) surrounding the cryptophane and whether or not a guest molecule is present inside the cavity of the host. To the best of our knowledge, this is the first example in which the nature of these counterions governs the chiroptical properties of a host molecule. Moreover, specific ECD spectra were obtained depending on the size of the guest molecules. This makes 1 a good sensor for small neutral molecules in aqueous solvent. Finally, VCD experiments associated with DFT calculations show that the chiroptical changes can be directly correlated to the presence of charges close to the aromatic rings and with a conformational change of the alkyl chains upon encapsulation.     

Design and synthesis of novel ionic liquid/liquid crystals (ILCs) with axial chirality

As the first examples of axially chiral ionic liquids, new pyridinium salts having a 1,3-dioxan ring in their central core were synthesized. Enantioselective dehydrohalogenation using chiral alkoxides provided a simple and practical approach for their synthesis. Some structures exhibit both low melting point and liquid crystalline behaviour.     

Further results on the euler and Genocchi numbers

Summary We characterize the ordinary generating functions of the Genocchi and median Genocchi numbers as unique solutions of some functional equations and give a direct algebraic proof of several continued fraction expansions for these functions. New relations between these numbers are also obtained.     

A Java-based control system for the Orsay tandem accelerator

A new control system was designed for the tandem MP-9 at Orsay. Because of the existing devices located on high voltage platforms and the lack of space inside the accelerator, in-house electronic cards based on micro-controllers and an optical fieldbus were developed to collect data. VME processors under VxWorks, a real time operating system, manage the fieldbus, concentrate the accelerator information and transmit it to the supervisory software through the ethernet network. This software consists of a collection of Java virtual machines (JVM) running on several Unix work-stations and PCs under Windows. Some of the Java virtual machines manage apparatus, instruments, local display and connections to an object database and VME concentrators. Other manage general synoptics. JVMs communicate between themselves with RMI protocol and JRPC with VME concentrators. So the supervisory software can be spread over several control stations throughout the network.