Bi2O3/FAp,a sustainable catalyst for synthesis of dihydro-[1,2,4]triazolo[1,5-a]pyrimidine derivatives through green strategy

The bismuth loaded on fluorapatite (Bi₂O₃/FAp) proved to be an excellent catalyst for the synthesis of novel dihydro-[1,2,4]triazolo[1,5-a]pyrimidine derivatives via a three-component reaction involving the mixture of 1H-1,2,4-triazol-5-amine, ethyl cyanoacetate or ethyl acetoacetate, and different benzaldehydes in ethanol at room temperature. The catalyst material was characterized by X-ray diffraction, Brunauer–Emmett–Teller surface area analysis, Fourier-transform infrared, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy techniques. The efficacy of Bi₂O₃/FAp as a heterogeneous catalyst was evaluated with the loading of different wt% of bismuth on FAp. The 2.5% bismuth on FAp performed extremely well as a catalyst with a high yield of products (92%–96%) in a short reaction time (25–35 min). The catalyst was recovered by simple filtration. It showed undiminished activity up to five runs. Simple work-up, room temperature reaction, short reaction time, high yields, no column chromatography, and good reusability of catalyst are the merits of the proposed protocol. In addition, this process offers 100% carbon efficiency and 98% atom economy with noteworthy fiscal and environmental benefits.     

One-pot green synthesis of novel 5,10-dihydro-1H-pyrazolo[1,2-b]phthalazine derivatives with eco-friendly biodegradable eggshell powder as efficacious catalyst

Research on Chemical Intermediates - An eco-friendly and efficient green protocol is developed for the synthesis of sixteen pyrazolo-phthalazine derivatives (5a–p) by using...     

Recent Progress in the Multicomponent Synthesis of Pyran Derivatives by Sustainable Catalysts under Green Conditions

Pyrans are one of the most significant skeletons of oxygen-containing heterocyclic molecules, which exhibit a broad spectrum of medicinal applications and are constituents of diverse natural product analogues. Various biological applications of these pyran analogues contributed to the growth advances in these oxygen-containing molecules. Green one-pot methodologies for synthesising these heterocyclic molecules have received significant attention. This review focuses on the recent developments in synthesising pyran ring derivatives using reusable catalysts and emphasises the multicomponent reaction strategies using green protocols. The advantages of the catalysts in terms of yields, reaction conditions, and recyclability are discussed.     

Synthesis of novel pyrazole‐based triazolidin‐3‐one derivatives by using ZnO/ZrO2 as a reusable catalyst under green conditions

An efficient approach for the synthesis of 10 novel pyrazole‐based 1,2,4‐triazolidin‐3‐one derivatives catalyzed by ZnO‐loaded ZrO₂ as heterogeneous catalyst with ethanol as solvent is described. The structure of the mixed metal oxide catalyst was characterized by various instrumental techniques (scanning electron microscopy, transmission electron microscopy, X‐ray diffraction and Brunauer–Emmett–Teller). In smooth reactions, products were accomplished in excellent yields (90–94%) with short reaction times (≈ 45 min). ZnO/ZrO₂ catalyst exhibited good recyclability. The catalyst is reused six times without any noticeable loss of activity. The major advantages of this method are operational simplicity, mild conditions, simple work‐up procedure and broad functional group tolerance.     

A viable and efficacious catalyst,CeO2/HAp,for green synthesis of novel pyrido[2,3-d]pyrimidine derivatives

Research on Chemical Intermediates - A facile one-pot green protocol at room temperature has been devised for the synthesis of novel pyrido[2,3-d]-pyrimidine derivatives catalyzed by CeO2-doped...     

Facile one-pot green synthesis of tetrahydrobiphenylene-1,3-dicarbonitriles in aqueous media under ultrasound irradiation

Research on Chemical Intermediates - An efficient and rapid procedure for the synthesis of 16 novel tetrahydrobiphenylene-1,3-dicarbonitrile derivatives (4a–p) is described, employing the...     

Reusable Ce‐V Loaded Alumina Catalyst for Multicomponent Synthesis of Substituted Pyridines in Green Media

Ce‐V/Al2O3 as an effective heterogeneous catalyst is synthesized by a simple technique. The catalyst was identified by powder X‐ray diffraction, SEM, TEM, and BET surface area analysis. The catalyst is fully recyclable and reusable for several runs preserving its high activity. The catalytic activity of Ce‐V/Al2O3 is described by synthesis of a series of multisubstituted pyridines in good to excellent yields via a facile one‐pot multicomponent reaction within shorter reaction time.     

Synthesis,Biological Activity of Pyrimidine Linked with Morpholinophenyl Derivatives

A new series of 5‐fluoro‐N⁴‐(3‐(4‐substitutedbenzylamino)phenyl)‐N²‐(4‐morpholinophenyl)pyrimidine‐2,4‐diamine derivatives ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j ) are prepared from using an intermediate compound 5‐fluoro‐N⁴‐(3‐(aminophenyl)‐N²‐(4‐morpholinophenyl)pyrimidine‐2,4‐diamine ( 5 ). The structures of the newly synthesized products are established from their spectral ¹H‐NMR, ¹³C‐NMR, ¹⁹F‐NMR, ESI‐MS, and analytical data. Here we report the synthesized compounds and larvicidal activity. All the compounds are screened for their significant larvicidal activity against third instar larvae at 24, 48, and 78‐h time exposure, and values were compared with standard drug Malathion. The Compounds 7i , 7a , 7c , 7f , and 7j exhibited significant activity. However the compounds 7b , 7e , 7d , and 7h showed excellent activity when compared to the above compounds and to standard drug malathion too because of the presence of mild electron withdrawing groups such as trifluoro, fluorine, hydroxy, nitro, and methoxy derivatives which are attached to the benzyl ring.     

Cholesterol Sequestration from Caveolae/Lipid Rafts Enhances Cationic Liposome-Mediated Nucleic Acid Delivery into Endothelial Cells

Delivering nucleic acids into the endothelium has great potential in treating vascular diseases. However, endothelial cells, which line the vasculature, are considered as sensitive in nature and hard to transfect. Low transfection efficacies in endothelial cells limit their potential therapeutic applications. Towards improving the transfection efficiency, we made an effort to understand the internalization of lipoplexes into the cells, which is the first and most critical step in nucleic acid transfections. In this study, we demonstrated that the transient modulation of caveolae/lipid rafts mediated endocytosis with the cholesterol-sequestrating agents, nystatin, filipin III, and siRNA against Cav-1, which significantly increased the transfection properties of cationic lipid-(2-hydroxy-N-methyl-N,N-bis(2-tetradecanamidoethyl)ethanaminium chloride), namely, amide liposomes in combination with 1,2-Dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) (AD Liposomes) in liver sinusoidal endothelial cells (SK-Hep1). In particular, nystatin was found to be highly effective with 2–3-fold enhanced transfection efficacy when compared with amide liposomes in combination with Cholesterol (AC), by switching lipoplex internalization predominantly through clathrin-mediated endocytosis and macropinocytosis.