CHEMBL5731884

DPP-IV Inhibitory Activity: 1. DPP-IV enzyme reaction buffer was prepared (50 mM HEPES (pH=7.8), 80 mM MgCl2, 150 mM NaCl, 1% BSA), and stored on ice for use; 2. The test compounds were diluted with DMSO from 10 mM to 1 mM (100-fold final concentration), and then diluted gradiently 3 folds in a 96-well plate to obtain 11 concentrations; DMSO was added to the twelfth well as a blank control, and then diluted 25 folds with the enzyme reaction buffer to 4-fold final concentration for use; 3. The DPP-IV enzyme reaction substrate H-Gly-Pro-AMC was thawed and diluted to 160 uM (4-fold final concentration) with the enzyme reaction buffer, and then stored on ice for use; 4. The rat plasma was thawed and diluted 100 folds (2-fold final concentration) with the enzyme reaction buffer, and then stored on ice for use; 5. 5 uL of the test compounds (4-fold final concentration) were added to a 384-well plate, and then L of the rat plasma (2-fold final concentration) was added, centrifuged and mixed well; 6. 5 uL of the enzyme reaction substrate H-Gly-Pro-AMC (4-fold final concentration) was added, centrifuged and mixed well, and then the 384-well plate was sealed with a film; 7. The resulting mixture was incubated in an incubator (22-23 C.) for 1 hour; 8. The fluorescence signal was determined using FlexStationI3 (Molecular devices) microplate reader (excited at 380 nm, and the emission spectrum was determined at 460 nm wavelength); 9. IC50 values of the test compounds in inhibiting DPP-IV activity were determined, i.e., calculating the IC50 values of the compounds using GraFit6 software.