CONCLUSION Use of DBU (an organocatalyst) as a base, operational simplicity, high yield of products and short reaction time are some of the significant advantages associated with the proposed strategy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.INTRODUCTION An effective Cu-complex, [Cu(NH3)4SO4 • H2O] was prepared conveniently from the inexpensive and easily available starting reagents in a simple route. MATERIALS AND METHODS Excellent reactivity of the catalyst was observed towards two competent clickcycloadditions (a) oxidative cycloaddition of azides with electron-poor olefins and (b) one-pot cycloaddition of alkynes with boronic acid and sodium azide under "click-appropriate" conditions.  https://www.selleckchem.com/products/gsk2879552-2hcl.html  RESULTS No external oxidant, short reaction time, high product yield, wide substrate scope, and aqueous solvent media make the azide-olefin cycloaddition approach a greener route in contrast to the reported methods. CONCLUSION The newly developed mild, green, and rapid three-component strategy shows product diversity with superb yields at room temperature by reducing the synthetic process time and using only 1 mol % of the synthesized copper complex. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.BACKGROUND A novel series of pyridine containing 1,3,4-oxa/thiadiazol derivatives 4a,b, pyrazole derivatives 5-7, thiazole derivatives 9a,b and 17a-c, urea derivatives 12a-c, imidiazole derivative 16, imidazo[1,2-a]pyridine derivatives 18a, b, tetrazole 19, pyrane 20 and pyridine derivatives 21 has been synthesized. OBJECTIVE This research aims to synthesize 6-(Trifluoromethyl)-2-[3-(trifluoromethyl)phenyl] amino nicotinohydrazide 2 and 6-(trifluoromethyl)-2-[3-(trifluoromethyl)phenyl]amino pyridin-3-carboaldhyde 15 as key intermediate for the synthesis of novel pyridine derivatives bearing different heterocyclic rings in order to study the additive effect of this ring toward tumor cell lines. METHODS 6-(Trifluoromethyl)-2-[3-(trifluoromethyl)phenyl]amino nicotinohydrazide 2 was synthesized in a series of synthetic steps and was used as key intermediate for the synthesis of compounds 3-(1,3,4- oxa/thiadiazol-2-yl)-6-(trifluoromethyl)-N-(3- trifluoromethyl) phenyl) pyridin-2-amine 4a,b, (3,5-dimethyl- 1Hhe molecules and the nature of the heterocyclic ring attached to the pyridine moiety. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.BACKGROUND A wide variety of dihydropyrimidins (DHPMs) exhibit pharmacological and biological activities. Herein, an efficient one-pot synthesis of some 3, 4-dihydropyrimidin-2(1H)-one derivatives is reported using Fe3O4 @SiO2-Pr-INH. OBJECTIVE Recently, several catalysts have been used to improve the Biginellis-reaction. However, some of these catalysts have imperfections. Herein, a convenient method for the synthesis of 3, 4-dihydropyrimidin- 2(1H)-ones and their sulfur derivatives using Fe3O4 @SiO2-Pr-INH is reported. MATERIALS AND METHODS Firstly, the catalyst was synthesized through a simple four-step method. The Fe3O4 MNPs were synthesized using the chemical co-precipitation method, coated with a layer of silica using TEOS, and then functionalized with CPTMS. Subsequently, a nucleophilic substitution of Cl by isoniazid resulted in the formation of the magnetic Fe3O4@SiO2-Pr-INH. After the preparation and characterization of Fe3O4@SiO2-Pr-INH, its catalytic activity was studied in the synthesis of 3, 4-d efficient catalyst for Biginelli-type synthesis of 3, 4-dihydropyrimidin-2(1H)-ones and 3, 4-dihydropyrimidin- 2(1H)-thiones in good to excellent yields and short reaction times. It is noteworthy that this method has several advantages such as simple experimental procedures, the absence of solvent, environmentally benign process, stability and reusability of the catalyst. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.AIMS AND OBJECTIVES A one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives by threecomponent cyclo-condensation of isatoic anhydride, aldehydes and amine or ammonium acetate has been developed using 3,5-Bis(trifluoromethyl) phenylammonium triflate (BFPAT) as a new organocatalyst. MATERIALS AND METHODS All of the obtained products are known compounds and identified by IR, 1HNMR, 13CNMR and melting points. RESULTS A wide variety of structurally different aldehydes reacted easily and rapidly to result in the relating 2,3-dihydroquinazolin-4(1H)-ones in good to excellent yield. CONCLUSION We have demonstrated an extremely effective and new process for synthesizing 2,3- dihydroquinazolin-4(1H)-ones employing BFPAT as a novel organocatalyst in one-pot fashion. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.BACKGROUND Quinoxaline 1,4-dioxides have a broad range of biological activity that causes a growing interest in their derivatives for drug discovery. Recent studies demonstrated that quinoxaline 1,4- dioxides have a promising anticancer activity and good hypoxia-selectivity. OBJECTIVE The preparation, isolation, structure characterization, and screening for anticancer activity of the first representatives of 6-substituted quinoxaline-2-carbonitrile 1,4-dioxides have been described. MATERIALS AND METHODS A series of 7- and 6-halogeno-3-phenylquinoxaline-2-carbonitrile 1,4-dioxides was synthesized by the Beirut reaction. The cytotoxicity was assessed by MTT test (72 h incubation) in normoxia (21% O2) and hypoxia (1% O2) conditions. RESULTS We found that during the Beirut reaction between a benzofuroxan bearing an electron withdrawing group and benzoylacetonitrile in the presence of triethylamine, in addition to well-known 7-substituted quinoxaline-2-carbonitrile 1,4-dioxides 7-11a, the 6-isomers 7-11b are formed. Moreover, the yield of the 6- isomers increased with the increase in the electron-withdrawing character of the substituent. For benzofuroxans with CO2Me and CF3 groups, 6-substituted quinoxaline-2-carbonitrile 1,4-dioxides 10-11b were the major products. Despite similarities in physicochemical and spectroscopic properties, the obtained isomers exhibit considerable differences in their anticancer activity and hypoxia selectivity. CONCLUSION Substituents and their electronic effects play a key role in the formation of 7- and 6-substituted quinoxaline-2-carbonitrile 1,4-dioxides in the Beirut reaction and in the cytotoxicity properties of the obtained isomers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.