Magnetically recoverable copper ferrite catalyzed cascade synthesis of 4-Aryl-1H-1,2,3-triazoles under microwave irradiation

Magnetically active CuFe₂O₄ catalyzed cascade synthesis of 4-Aryl-1H-1,2,3-triazoles under microwave irradiation starting from aromatic aldehydes, sodium azide and nitromethane has been developed and demonstrated here. The catalyst system needed for the purpose was prepared following a procedure by A. Dandiya et al. with a slight modification and was characterized using FT-IR, XRD, SEM-EDX and TEM analysis. The most notable advantage of the developed methodology is the excellent time economy to carry out the transformation. Other features include simple operating procedure, wide substrate coverage and easy recovery of the catalyst. Reusability of the catalyst has been tested and found to be very satisfactory up to sixth cycle without significant loss in efficiency. All the synthesized compounds have been characterized using FTIR, ¹H & ¹³CNMR spectroscopy, HRMS.     

A novel three-component one-pot synthesis of pyrano[2,3-d]pyrimidines and pyrido[2,3-d]pyrimidines using microwave heating in the solid state

Microwave-assisted three-component cyclocondensation of barbituric acids 1, benzaldehyde 2 and alkyl nitriles 3 proceeds in the absence or presence of triethylamine to afford pyrano[2,3-d]pyrimidines 4 and 6-aminouracils 5 or 6-hydroxyaminouracils 6 react with 2 and 3 under identical conditions to yield pyrido[2,3-d]pyrimidines 7, all in high yields.     

Synthesis of pectin-N,N-dimethyl acrylamide hydrogel by gamma radiation and application in drug delivery (in vitro)

The objective of the work is to synthesize pectin-N, N-Dimethylacrylamide (DMAA) hydrogel by gamma radiation without using any initiators and cross-linking agents. Effect of radiation doses on gel fraction and equilibrium swelling as a function of pH were studied, and 5 kGy radiation dose was found to be the optimum dose for hydrogel synthesis. The grafting /crosslinking was investigated by Fourier transform infrared spectroscopy. Thermal properties and surface morphology were studied by differential scanning calorimetry and scanning electron microscopy. To study the drug release kinetics, 5-fluorouracil was loaded into the hydrogel and in vitro release was carried out in simulated gastric and intestinal fluid. The release profile of drug showed that more than 90% of the loaded drugs were released after 4 hours at both gastric fluid and intestinal fluid pH. Drug release data was fitted into zero order, Higuchi and Korsmeyer-Peppas kinetic models. Higuchi model was found to be the best fitted and release exponent ‘n’ value of Korsmeyer-Peppas model indicated the non-Fickian transport.     

Construction of unsymmetrical bis-urea macrocyclic host for neutral molecule and chloride-ion binding

Construction of synthetic macrocyclic host that can bind with neutral molecules and anions has potential applications in supramolecular chemistry. Herein, we have designed and synthesized blue light emitting an unsymmetrical neutral bis-urea macrocyclic host. This macrocycle can bind with neutral DMF molecule (1:1) as well as Cl⁻ ion (1:1) through noncovalent interactions. X-Ray crystal structure, ¹H NMR titrations with Job's Plot, HRMS with isotropic distribution pattern, FT-IR, and density functional theory analysis revealed the binding of bis-urea macrocyclic host with the guest molecule.