Changes in xanthophyll esterification degree during pepper fruit ripening have been studied in five cultivars (Numex, Mana, Belrubi, Delfin, and Negral). Esterification of xanthophylls with fatty acids is seen to be a process that is contemporary with and directly linked to the transformation of chloroplast (present in the green fruit) into chromoplast (present in the red fruit). Changes in the...

making impression to obtain an accurate working cast needs to use accurate impression materials such as polyether. on the other hand, polyether cannot be used easily in places with undercut such as excessive interproximal spaces and under the pontics of fixed partial dentures as it may be locked in these free spaces. in this article, a method is presented to blockout interproximal spaces in ord...

Some 3, 5-diacyl or 3,5-diester 1,4-dihydropyridines were oxidized to the corresponding pyridine derivatives using hydrogen peroxide in aqueous ethanol in the presence of potassium bromide and acetic acid as the catalysts. The reaction was carried out in ethanol and products were isolated in high to excellent yields. However, oxidation of 3,5-diacetyl 1,4-dihydropyridines is slower than 3,5-die...

(Carbo)nucleoside derivatives constitute an important class of pharmaceuticals, yet there are only few convergent methods to access new analogues. Here, we report the first synthesis of thymine-, uracil-, and 5-fluorouracil-substituted diester donor-acceptor cyclopropanes and their use in the indium- and tin-catalyzed [3+2] annulations with aldehydes, ketones, and enol ethers. The obtained dies...

Perovskite thin films with various functional properties have been synthesized through the Metal Organic Chemical Vapour Deposition (MOCVD). The MOCVD processes, used for the fabrication of a variety of advanced materials in thin film form, rely upon application of a molten multi-element source. The challenging in-situ strategy involves the use of a molten source consisting of a second-generati...

The chemical composition of plant polyphenols Plantago major L. and lanceolata growing in Uzbekistan was studied. More than 20 compounds, including 7 flavonoids, 9 phenolic acids, 8 hydrolysable tannins, the ages which have been determined using physicochemical methods research isolated from plants. From P. L., along with well-known such as gallic acid, rutin, luteolin, isorhamnetin, hyperoside...

3-Methylindole, a ruminal fermentation product of tryptophan, induces acute pulmonary edema and emphysema in cattle, and 3-methylindole is present in the ruminal fluid and blood of cows with a natually occurring form of this disease. Monensin, a polyether antibiotic and widely used feed additive for beef cattle, prevented tryptophan-induced acute bovine pulmonary edema and emphysema. Monensin a...

A series of chalcone-based macrocyclic ethers have been synthesized. These macrocyclic ethers contain polyether as well as extended conjugation to the benzene ring to function as fluorescent sensor for cations. The modeling studies show that the chalcone part of the receptors remains partially out of plane from the polyether part and the keto moiety of the receptors always directed outwardly in...

Tetronomycin, C34H50O8, isolated from a strain of Streptomyces sp. nov. represents a novel polycyclic ionophore polyether. The crystal structure and absolute configuration were established by X-ray analysis of the mono-O-acetyltetronomycin silver salt. Tetronomycin is the first metabolic polyether which contains a tetronic acid moiety instead of the essential carboxylic acid function. A trisubs...