6271-51-8Relevant academic research and scientific papers
A one-pot and three-component synthetic approach for the preparation of asymmetric and multi-substituted 1,4-dihydropyrazines
Peytam, Fariba,Adib, Mehdi,Shourgeshty, Reihaneh,Rahmanian-Jazi, Mahmoud,Jahani, Mehdi,Larijani, Bagher,Mahdavi, Mohammad
supporting information, (2019/11/11)
An efficient, one-pot and three-component synthesis of a new series of 2-acyl-3,4,6-triaryl-1,4-dihydropyrazines is described. This two-step strategy involves treatment of phenacyl bromides and anilines to give the nucleophilic substitution intermediate f
A new synthetic strategy towards 2,4,5-trisubstituted 1H-imidazoles and highly substituted pyrrolo[1,2-c]imidazoles by use of α-azidochalcones via Michael addition-cyclization followed by Wittig reaction
Adib, Mehdi,Peytam, Fariba,Rahmanian-Jazi, Mahmoud,Bijanzadeh, Hamid Reza,Amanlou, Massoud
, p. 6696 - 6705 (2017/10/25)
Efficient and facile protocols for the preparation of highly functionalized 1H-imidazoles and 5H-pyrrolo[1,2-c]imidazoles are described. Heating a mixture of an α-azidochalcones and N,N,N′,N′-tetramethyl guanidine under neat conditions gave the corresponding 2,4,5-trisubstituted 1H-imidazole via Michael addition-cyclization in excellent yields. Subsequently, the prepared 1H-imidazoles undergo addition-Wittig reaction with acetylenic esters in presence of triphenylphosphine in dichloromethane to afford 5H-pyrrolo[1,2-c]imidazoles in high yields.
I2O5-mediated bromohydroxylation and dibromination of olefins using KBr in water
Wang, Yajun,Wang, Jinxi,Xiong, Yun,Liu, Zhong-Quan
supporting information, p. 2734 - 2737 (2014/05/06)
An efficient and green bromohydroxylation and dibromination of various olefins mediated by I2O5 has been developed in this work. A series of olefins gave the corresponding α-bromo-alcohols and dibromides as the major products using KBr as the brominating reagent in aqueous medium at room temperature. The diastereo- and regio-selectivities are extremely high.
Ecofriendly bromination of chalcones and synthesis of flavones using grinding technique
Jakhar, Komal,Makrandi
, p. 141 - 145 (2013/02/23)
Selective bromination of chalcones and 2'-hydroxychalcones has been carried out with ammonium bromide and ammonium persulphate using grinding technique at RT under aqueous moist condition to give α,β-dibromochalcones and α,β-dibromo-2'- hydroxychalcones respectively. α,β- Dibromo-2'-hydroxychalcones have been cyclodehydrobrominated with barium hydroxide moist and ethanol at RT to give flavones using grinding technique.
Process for preparing vinyl substituted beta-diketones
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Page/Page column 8, (2008/06/13)
A process for preparing vinyl substituted beta-diketones includes reacting a halogen-containing beta-diketone with an olefin in a reaction zone under Heck coupling reaction conditions in the presence of a catalyst, a base, and an organic phosphine to provide a vinyl substituted beta-diketone product.
Imidazo[2,1-b]thiazole derivatives XII. Synthesis and immunoactivity in vitro on human T lymphocyte of several 3-aroylmethyl and 2-aroyl-3-methyl(aryl)-5,6-dihydroimidazo[2,1-b]thiazoles
Robert,Hassanine,Harraga,Seilles
, p. 261 - 271 (2007/10/02)
To estimate the influence of aryl group position on the immunostimulant properties of imidazo[2,1-b]thiazole derivatives, several compounds were obtained and tested, versus tetramisole hydrochloride, on the mobilisation of CD2 receptor by human T lymphocyte. The synthesis use the action of monobrominated β-diketones on the 2-mercaptoimidazoline. So, 1-aryl-4-bromobutane-1,3-diones lead to 3-aroylmethyl-5,6-dihydroimidazo[2,1-b]thiazoles 4. Same, 1-aryl-2-bromobutane-1,3-diones and 1,3-diaryl-2-bromopentane-1,3-diones give respectively 3-aroyl-2-methyl-5,6-dihydroimidazo[2,1-b]thiazoles 5 and 3-aroyl-2-aryl-5,6-dihydroimidazo[2,1-b]thiazoles 6. Better yields are obtained when the reaction presents two steps. The first one, realized in acetone at room temperature, leads to an intermediate S-substituted 4,5-dihydroimidazole which, in second step, is cyclized in imidazo[2,1-b]thiazole compound via an unisolated carbinolamine. This one explains the univocal formation of 5 derivatives and the feasible blending in case of 6. The immunoactivity of several imidazothiazoles 4, 5 and 6 is lower that them of 6-aryl substituted compounds and particularly that the levamisole which is the reference product in this series.
