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Conversion of carbohydrates into 5-hydroxymethylfurfural (HMF) is a valuable reaction for biomass efficient utilization. The silica-supported phosphotungstic acid (PTA) heterogeneous catalyst (SiO 2 -ATS-PTA) was prepared and characterized by XRD, FT-IR, pyridine-FTIR and SEM. The SiO 2 -ATS-PTA was used to catalyze the conversion of glucose, and it afforded 78.31% yield of HMF at 160 °C for 140 min. The SiO 2 -ATS-PTA could be reused for five runs without significant loss of catalytic activity. Furfural was the main byproduct. A kinetic analysis was carried out and the values of the activation energy and the pre-exponential factor for the reaction were 30.25 kJ mol −1 and 1.08 × 10 7  min −1 , respectively. [ABSTRACT FROM AUTHOR]

In order to develop novel long-acting GLP-1 derivatives, a peptide hybrid ( 1a ) from human GLP-1 and Xenopus GLP-1 discovered in our previous research was selected as the lead compound. Exendin-4 inspired modification resulted in peptide 1b with enhanced glucose-lowering activity. Cysteine mutated 1b derivatives with reserved bioactivity were further site-specifically connected with mPEG 2000 -MAL to provide conjugates 3a – h , among which 3d and 3e were found to have significantly improved hypoglycemic activity and insulinotropic ability than GLP-1. The hypoglycemic durations of 3d and 3e were remarkably prolonged to ∼20 h in type 2 diabetic db/db mice, compared with the 5.3 h of exendin-4 in the same test. Finally, chronic in vivo studies revealed that a once-daily treatment of 3d or 3e for five weeks resulted in recovered glucose-controlling ability of type 2 diabetic db/db mice, along with other benefits, such as reduced body weight gains, food intake amounts and HbA1c values. Collectively, our results suggest 3d and 3e as potential long-acting glucose-lowering agents for treating type 2 diabetes. [ABSTRACT FROM AUTHOR]