The development of potent and selective bisarylmaleimide GSK3 inhibitors.

Many 3-aryl-4-(1,2,3,4-tetrahydro[1,4]diazepino[6,7,1-hi]indol-7-yl)maleimides exhibit potent GSK3 inhibitory activity (<100 nM IC(50)), although few show significant selectivity (>100x) versus CDK2, CDK4, or PKCbetaII. However, combining 3-(imidazo[1,2-a]pyridin-3-yl), 3-(pyrazolo[1,5-a]pyridin-3-yl) or aza-analogs with a 4-(2-acyl-(1,2,3,4-tetrahydro[1,4]diazepino[6,7,1-hi]indol-7-yl)) group on the maleimide resulted in very potent inhibitors of GSK3 (160 to >10,000-fold selectivity versus CDK2/4 and PKCbetaII. These compounds also inhibited tau phosphorylation in cells and were effective in lowering plasma glucose in a rat model of type 2 diabetes (ZDF rat).

Comparative analyses of a small molecule/enzyme interaction by multiple users of Biacore technology.

To gauge the experimental variability associated with Biacore analysis, 36 different investigators analyzed a small molecule/enzyme interaction under similar conditions. Acetazolamide (222 g/mol) binding to carbonic anhydrase II (CAII; 30000 Da) was chosen as a model system. Both reagents were stable and their interaction posed a challenge to measure because of the low molecular weight of the analyte and the fast association rate constant.