The discovery of a novel series of glucokinase activators based on a pyrazolopyrimidine scaffold.

Glucokinase is a key enzyme in glucose homeostasis since it phosphorylates glucose to give glucose-6-phosphate, which is the first step in glycolysis. GK activators have been proven to lower blood-glucose, and therefore have potential as treatments for type 2 diabetes. Here the discovery of pyrazolopyrimidine GKAs is reported. An original singleton hit from a high-throughput screen with micromolar levels of potency was optimised to give compounds with nanomolar activities. Key steps in this success were the introduction of an extra side-chain, which increased potency, and changing the linking functionality from a thioether to an ether, which led to improved potency and lipophilic ligand efficiency. This also led to more stable compounds with improved profiles in biological assays.

Novel structures derived from 2-[[(2-pyridyl)methyl]thio]-1H-benzimidazole as anti-Helicobacter pylori agents, Part 1.

2-[[(2-Pyridyl)methyl]thio]-1H-benzimidazoles (2, sulfides) exhibit antibacterial properties that are selective for Helicobacter spp., but they also have an inherent susceptibility to metabolic oxidation to furnish 2-[[(2-pyridyl)methyl]sulfinyl]-1H-benzimidazoles (1), which act as proton pump inhibitors (PPIs). We have discovered five compounds with retained antibacterial potency and selectivity in which the overall framework of the sulfides 2 could be kept intact while structural modifications were made to remove PPI activity. These compounds, 2-[((2-methyl-3-(2-(2-(2-methoxyethoxy)ethoxy)ethylthio)phenyl)methyl)thio]-1H-benzimidazole (79), 2-[((2-methyl-3-(2-(2-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)ethoxy)ethylthio)phenyl)methyl)thio]-1H-benzimidazole (80), 2-[((2-methyl-3-((2-morpholino)ethylthio)phenyl)methyl)thio]-1H-benzimidazole (86), 2-[[[2-methyl-3-[2-(2-methyl-5-nitroimidazol-1-yl)ethylthio]phenyl]methyl]thio]-1H-benzimidazole (88), and 2-[[[2-methyl-3-[2-(1,2,4-triazol-1-yl)ethylthio]phenyl]methyl]thio]-1H-benzimidazole (89), had minimum bactericidal concentrations (MBCs) of 0.5, 0.5, 1, 2, and 4 microg/mL, respectively. The reported compounds are bactericidal with MBCs within 1 order of magnitude of MBCs of clinically used antimicrobials such as clarithromycin (0.1 microg/mL) or metronidazole (2-4 microg/mL) but differ from these inasmuch that they have an extremely narrow spectrum activity and appear to be species specific.