Discovery, development, chemical diversity and design of isoxazoline-based insecticides.

Isoxazoline is a 5-membered heterocycle present in the active compounds of many commercial veterinary anti-ectoparasitic products. The molecular target of isoxazolines is the inhibition of GABA-gated chloride channels in insects. These facts have inspired the use of the isoxazoline scaffold in the design of novel insecticide compounds.

Insight into Out-of-Layer Fluctuations in the Smectic A Stability of 3,5-Diarylisoxazole Liquid Crystals.

Polar-terminated 3,5-diarylisoxazole liquid crystals (ILCs) were synthetized and characterized. ILCs are composed by rigid core 3,5-diarylisoxazol, alkyl chain and polar-terminated flexible spacer. Hydroxyl-, ketal- and 1,2-diol-terminated ILCs rendered smectic C and A mesophase, while bromine-terminated ILCs showed smectic A and B mesophase, for monosubstituted and linear ILCs.

The use of isoxazoline and isoxazole scaffolding in the design of novel thiourea and amide liquid-crystalline compounds.

A series of novel thiourea and amide liquid crystals containing 5-membered isoxazoline and isoxazole rings were synthetized and the liquid crystal properties studied. Thioureas were obtained using a condensation reaction of benzoyl chlorides, arylamines and ammonium thiocyanate. The amides, on the other hand, were the byproduct of a quantitative reaction which used potassium cyanate as the starting material.

Crystal structure of 5-(4--but-oxy-phen-yl)-3-(4--octyloxyphen-yl)-4,5-di-hydro-isoxazole.

The mol-ecule of the title compound, CHNO, was prepared by [3 + 2] 1,3-dipolar cyclo-addition of 4--octyl-phenyl-nitrile oxide and 4--but-oxy-styrene, the latter compound being a very useful inter-mediate to the synthesis of liquid-crystalline materials. In the mol-ecule, the benzene rings of the -octyloxyphenyl and -but-oxy-phenyl groups form dihedral angles of 2.83 (7) and 85.

Synthesis and thermal behavior of new N-heterotolan liquid crystals.

[reaction: see text] The synthesis of liquid crystal series 9a-d was achieved using the Buchwald protocol and Sonogashira reaction.