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Aza-Michael addition of sulfonamides to Į,ȕ-unsaturated esters efficiently proceeds in the presence of catalytic amount of sodium hydroxide (NaOH) and tetrabutylammonium bromide (TBAB) as a phase-transfer catalyst (PTC) under microwave irradiation to afford N,N-dialkyl sulfonamides as biologically interesting compounds in good to excellent yields and short reaction times.

A novel Pd−NHC functionalized metal–organic framework (MOF) based on MIL‐101(Cr) was synthesized and used as an efficient heterogeneous catalyst in the C‐C bond formation reactions. Using this heterogeneous Pd catalyst system, the Suzuki−Miyaura coupling reaction was accomplished well in water, and coupling products were obtained in good to excellent yields in short reaction time. The Pd−NHC−MIL‐101(Cr) was characterized using some different techniques, including Fourier transform‐infrared, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy, inductively coupled plasma and elemental analysis. The microscopic techniques showed the discrete octahedron structure of MIL‐101(Cr), which is also stable after chemical modification process to prepare the catalyst system. The TEM images of the catalyst showed the existence of palladium nanoparticles immobilized in the structure of the catalyst, while no reducing agent was used. It seems that the NHC groups and imidazolium moieties in the structure of the MOF can reduce Pd (II) to Pd (0) species. This modified MOF substrate can also prevent aggregation of Pd nanoparticles, resulting in high stability of them in organic transformation. The Pd−NHC−MIL‐101(Cr) catalyst system could be simply extracted from the reaction mixture, providing an efficient synthetic method for the synthesis of biaryls derivatives using the aforementioned coupling reaction. The Pd−NHC−MIL‐101(Cr) catalyst could be recycled in this organic reaction with almost consistent catalytic efficiency.

Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels and instability in carbohydrate metabolism. For treating diabetes, one important therapeutic approach is reducing the postprandial hyperglycemia which can be managed by delaying the absorption of glucose through inhibition of the carbohydrate-hydrolyzing enzymes, α-amylase (α-Amy) and αglucosidase (α-Gls) in the digestive tract. In this work, a new class of curcumin derivatives incorporating pyrano[2,3-d]pyrimidine heterocycles was synthesized using a multicomponent reaction between curcumin, aldehydes, and barbituric acid. Using UV-Vis spectroscopic method, the synthetic compounds were assessed for their inhibitory properties against α-Amy and α-Gls enzymes. Also, the antioxidant potential of these compounds was measured spectroscopically and compared with Trolox which is known as a gold standard to measure antioxidant capacity. The results of present study suggest that the curcumin derivatives were able to efficiently inhibit both yeast and mammalian α-Gls. In comparison with the antidiabetic medicine acarbose, the synthetic curcumin derivatives were also capable to inhibit more effectively the yeast α-Gls. The partial inhibitory effects of these compounds against pancreatic α-Amy were also important in the terms of avoiding development of the possible gastrointestinal side effects. Moreover, some of the curcumin derivatives indicated stronger antioxidant activity than Trolox. Overall, these synthetic curcumin analogues might be considered as novel molecular templates for development of efficient antidiabetic compounds with promising inhibitory activities against α-Amy and α-Gls enzymes.

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An efficient, simple and solvent-free method for highly regioselective N-alkylation of benzotriazole in the presence of SiO 2 , K 2 CO 3 and tetrabutylammonium bromide (TBAB) under thermal and microwave conditions has been described. In this method, 1-alkyl benzotriazoles were obtained regioselectively in moderate to high yields and short reaction times.