نتایج جستجو برای: Amines
تعداد نتایج: 20593 فیلتر نتایج به سال:
حفاظت از گروههای عاملی از مراحل اجتناب ناپذیر در سنتز آلی است، در این بین محافظت از گروههای آمینی بسیار حائز اهمیت است. روشهای متعددی از قبیل فرمیله کردن، استیله کردن، محافظت بصورت boc و موارد زیاد دیگری جهت محافظت از گروههای آمینی تاکنون گزارش شده است. از طرف دیگر توسعه و کاربرد کاتالیست ها و حلالهای دوستدار محیط زیست و مزایای واکنشهای بدون حلال همچون سرعت بالای واکنش، خالص سازی آسان، کاهش آلو...
Biomimetic aerobic oxidation of primary benzylic amines has been achieved by using a quinone catalyst. Excellent selectivity is observed for primary, unbranched benzylic amines relative to secondary/tertiary amines, branched benzylic amines, and aliphatic amines. The exquisite selectivity for benzylic amines enables oxidative self-sorting within dynamic mixtures of amines and imines to afford h...
2,6-diaminopyridine is extensively used as a pharmaceutical intermediate and a hair dye coupler as oxidation formulations. it is soluble in protic solvents. primary and secondary amines are n-methylated by various methods such as direct alkylation of amines with hofmann mechanism, but in many of these methods due to overalkylations, we earn a mixture of amino products. consequently, they aren't...
2,6-diaminopyridine is extensively used as a pharmaceutical intermediate and a hair dye coupler as oxidation formulations. It is soluble in protic solvents. Primary and secondary amines are N-methylated by various methods such as direct alkylation of amines with Hofmann mechanism, but in many of these methods due to overalkylations, we earn a mixture of amino products. Consequently, they aren't...
We have introduced a selective synthesis of tertiary amines using alkyl halide and ammonium salts as the amine sources in water. This green process has outstanding superiorities, such as being eco-friendly, possessing ammonium salts, and using water as a green solvent in the absence of organic ligands or catalysts. It is worth mentioning that the presence of t-Butyl alcohol and potassi...
Nitriles were found to be highly effective alkylating reagents for the selective N-alkylation of amines under catalytic hydrogenation conditions. For the aromatic primary amines, the corresponding secondary amines were selectively obtained under Pd/C-catalyzed hydrogenation conditions. Although the use of electron poor aromatic amines or bulky nitriles showed a lower reactivity toward the reduc...
The unicellular eukaryote Tetrahymena synthesize, store and secrete biogenic amines (histamine, serotonin, epinephrine, dopamine, melatonin) and also can take up amines from the milieu. It also has (G-protein-coupled) receptors (binding sites) for these amines as well, as second messengers. The factors infuencing the mentioned processes are shown. For certain amines the genes and the coded enzy...
Aromatic amines are an important group of industrial chemicals, which are widely used for manufacturing of dyes, pesticides, drugs, pigments, and other industrial products. These compounds have been considered highly toxic to human beings due to their carcinogenic nature. Three groups of aromatic amines have been recognized: monocyclic, polycyclic, and heterocyclic aromatic amines. Bacterial de...
یکی از مشتقات ترکیبات آلی کربنیل دار اکسیم (oxime) می باشد به علت اینکه اکسیمها به راحتی قابل تبدیل به گروههای عاملی دیگر هستند، در سنتز مواد دیگر به طور وسیع به کارگرفته می شوند. از جمله مواد سنتز شده از اکسیم: نایترونها (nitrones) و هیدرکسیل آمینها (hydroxyl amines) می باشند که در این پایان نامه بررسی شده است. از اکسیمها و نایترونها و هیدروکسیل آمینها مواد متعددی سنتز شده است که د...
biogenic amines (ba) are nitrogenous compounds that possess biological activity. the source of production is the microbial decarboxylation of amino acids. this compounds are found in various types of cheese. the aim of this work was to evaluate the ba content of some traditional cheeses in west azerbaijan province iran. for this purpose, 70 samples of koopeh, 10 samples of lighvan and 5 samples...
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