New p-tert-butyl thiacalix[4]arenes differently substituted at the lower rim with amide, hydroxyl and ester groups were synthesized. Binding properties of the compounds toward some tetrabutylammonium salts n-Bu(4)NX (X = F(-), Cl(-), Br(-), I(-), CH(3)CO(2)(-), H(2)PO(4)(-), NO(3)(-)) were studied by UV spectroscopy. It was found that the stoichiometry of the complexes, generally, is 1 : 1, and...

A green method for the synthesis of high-performance diketopyrrolopyrrole pigments using diethyl succinate in the presence of mixture of ionic liquids is reported. Although, alkaline condition is needed in the succinate ester route for synthesis of the pigments, in the present study, the replacement possibility of conventional organic base by mixture of BMIMOH and BMIMBF4 ionic liquids was inve...

α-Glucosidase inhibitors decrease the cleavage- and absorption rate of monosaccharides from complex dietary carbohydrates, and represent therefore an important class of drugs for management of type 2 diabetes. In this study, a defatted ethyl acetate extract of Eremanthus crotonoides leaves with an inhibitory concentration (IC50) of 34.5 μg/mL towards α-glucosidase was investigated by high-resol...

The rate constants for exchange of hydrogen for deuterium at the α-CH(2) positions of 8-(N,N-dimethylaminonaphthalen-1-yl)acetic acid tert-butyl ester 1 and naphthalen-1-ylacetic acid tert-butyl ester 2 have been determined in potassium deuteroxide solutions in 1 : 1 D(2)O : CD(3)CN, in order to quantify the effect of the neighbouring peri-dimethylamino substituent on α-deprotonation. Intramole...

The Michael addition of dibenzylamine to (+)-tert-butyl perillate (3) and to (+)-tert-butyl phellandrate (6), derived from (S)-(-)-perillaldehyde (1), resulted in diastereomeric β-amino esters 7A-D in a moderately stereospecific reaction in a ratio of 76:17:6:1. After separation of the diastereoisomers, the major product, cis isomer 7A, was quantitatively isomerized to the minor component, tran...

Synthesis of optically pure a-tert-butyl 0-methyl (2S,3R)-3-ethylhexahydroquinolinate (18) in 54-59% yield from L-aspartic acid was the foundation for a practical synthesis of (+)-vincamine. Conversion of L-aspartic acid to 18 was accomplished via two routes. In the first route, esterification was followed by mono-N-alkylation to attach the three-carbon residue. Nitrogen protection and intramol...

The objective of this study was to evaluate the immobilization of lipase on a chitosan support by physical adsorption, aiming at its application in hydrolytic and synthetic reactions. Two types of chitosan (flakes and porous) were used for immobilizing lipase from a microbial source (Candida rugosa) and animal cells (porcine pancreas). The best results for recovery of total activity after immob...

A versatile automated synthesis apparatus, equipped with a chemical artificial intelligence, was developed to prepare and isolate a wide variety of compounds. The apparatus was to the synthesis of substituted N-(carboxyalkyl)amino-acids. The apparatus [1,2] is composed of units for performing various tasks,for example reagent supply, reaction, purification and separation, each linked to a contr...

Thermoplastic starch/butyl glycol ester copolymer/polylactic acid (TPS/PBSA/PLA) biodegradable composites were prepared by melt-mixing. The structure, microstructure, mechanical properties and heat resistance of the TPS/PBSA/PLA studied Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), tensile test thermogravimetry tests, respectively. results showed that PBSA ...

The article presents the herbicidal, defoliating, fungicidal properties of synthesized derivatives benzoxazolinones and benzoxazolinethions. It was shown that 3-alkylbenzoxazolinones, 3-alkyl-6-halobenzoxazolinones 2-alkylthiobenzoxazoles exhibit herbicidal action during growing season plants, they also cause cotton leaves to drop up 70%. found 3-alkylbenzoxazolinones exhibited activity against...