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991.
In this study, we have synthesized 1‐(4,6‐disubstitutedpyrimidin‐2‐yl)‐3‐(3,5‐dinitrobenzoyl)‐thiourea derivatives ( 1a , 1b , 1c , 1d , 1e , 1f , 1g , 1h ) and N‐[(2Z)‐3‐(4,6‐disubstitutedpyrimidin‐2‐yl)‐4‐phenyl‐1,3‐thiazol‐2(3H)‐ylidene]‐3, 5‐dinitrobenzamide ( 2a‐2h ) analogues and characterized by IR spectroscopy, NMR spectroscopy, elemental analysis, and single crystal X‐ray diffraction data. The compounds ( 2a‐2h ) were screened for antimicrobial activity against Gram positive, Gram negative, and fungal species. The results of antimicrobial study indicated that compounds showed most potential and appreciable antibacterial and antifungal activities. 相似文献
992.
A solvent‐free reaction between urea/thiourea, dimedone and aromatic aldehydes in the presence of catalytic amounts of zirconium (IV) oxychloride octahydrate (ZrOCl2.8H2O) as a powerfull Lewis acid leads to octahydroquinazolinone/thione derivatives in good yields. This method has advantages such as avoidance of the organic solvents, production of pure products without any by‐product, short reaction times and simple operation. 相似文献
993.
The article describes ionic liquids [bmim][NO3] in the presence of 30% mol CuI as efficient media for the domino Knoevenagel–hetero–Diels–Alder reaction of o-propargyloxy benzaldehydes as unactivated terminal alkynes with some active methylene compounds. Short reaction time, easy workup, good to excellent yields, and mild conditions are advantages of this new media. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
994.
An efficient synthesis of some novel 2-aroylimino-3-aryl-4-phenyl-1,3-thiazolines was carried out by base-catalyzed cyclization of 1-aroyl-3-arylthioureas with acetophenone in the presence of bromine. The structures were confirmed by spectroscopic data, elemental analyses, and in one case (2t) by single-crystal X-ray diffraction data. 相似文献
995.
Ali Sharifi M. Saeed Abaee Azam Tavakkoli Mojtaba Mirzaei Alireza Zolfaghari 《合成通讯》2013,43(17):2958-2966
Microwave-assisted and thermal condensations of aromatic and aliphatic aldehydes with β-naphthol adsorbed onto montmorillonite K-10 were conducted in a one-pot procedure leading to the formation of a variety of xanthene derivatives. Under microwave irradiation, reactions completed within 4–6 min. The procedure is applicable to both aromatic and aliphatic aldehydes, and the catalyst was recycled and reused efficiently in later reactions. 相似文献
996.
M. Saeed Abaee Mohammad M. Mojtahedi M. Mehdi Zahedi S. Mohammad Bolourtchian 《合成通讯》2013,43(2):199-206
A remarkably efficient double‐crossed aldol condensation of tetrahydropyran‐4‐one with a variety of aromatic aldehydes is described at room temperature in the presence of (trimethylsilyl)diethylamine and lithium perchlorate under solvent‐free conditions. Excellent yields of 3,5‐bis(arylmethylidene)pyranones are achieved in a facile one‐pot general procedure. 相似文献
997.
A series of 2-, 3-, and 4-substituted (fluorobenzoylimino)-3-aryl-4-methyl-1,3-thiazolines (2a–j) were synthesized in good yields by the base-catalyzed cyclization of corresponding 1-(fluorobenzoyl)-3-(fluorophenyl)thioureas (1a–j) with α-bromoacetone in water. Compared to the reactions in conventional nonaqueous solvents under inert anhydrous conditions, the aqueous medium provides a much cleaner, more efficient, and simpler method for synthesis. 相似文献
998.
One-pot, three-component reaction of 2-naphthol, aromatic aldehyde, and heteroaryl amine in water at room temperature leads to the formation of the corresponding aminonaphthols (Betti bases). Reaction details and study of enantiomeric resolution of 1-(p-methylphenyl (2-pyrazinylamino) methyl) naphthalene-2-ol with the aid of 1H NMR spectroscopy using chiral europium shift reagent is presented. 相似文献
999.
The Darzens condensation of α‐chloroacetophenone with various aromatic aldehydes mediated by potassium fluoride on alumina at room temperature resulted in formation of good to excellent yields of trans‐α,β‐epoxy ketones in short time periods. 相似文献
1000.
Tetra‐n‐butylammonium hydroxide (TBAH) has been utilized as a novel and efficient catalyst for the Knoevenagel condensation of aldehydes with acidic methylene compounds such as methyl‐ and ethylcyanoacetate, malononitrile, and cyanoacetamide to afford substituted olefins. 相似文献