Leucine Motifs Stabilize Residual Helical Structure in Disordered Proteins.

Many examples are known of regions of intrinsically disordered proteins that fold into α-helices upon binding to their targets. These helical binding motifs (HBMs) can be partially helical also in the unbound state, and this so-called residual structure can affect binding affinity and kinetics. To investigate the underlying mechanisms governing the formation of residual helical structure, we assembled a dataset of experimental helix contents of 65 peptides containing HBM that fold-upon-binding.

Regioselective Synthesis of 5- and 3-Hydroxy--Aryl-1-Pyrazole-4-Carboxylates and Their Evaluation as Inhibitors of Dihydroorotate Dehydrogenase.

In silico evaluation of various regioisomeric 5- and 3-hydroxy-substituted alkyl 1-aryl-1-pyrazole-4-carboxylates and their acyclic precursors yielded promising results with respect to their binding in the active site of dihydroorotate dehydrogenase of (DHODH). Consequently, four ethyl 1-aryl-5-hydroxy-1-pyrazole-4-carboxylates and their 3-hydroxy regioisomers were prepared by two-step syntheses via enaminone-type reagents or key intermediates. The synthesis of 5-hydroxy-1-pyrazoles was carried out using the literature protocol comprising acid-catalyzed transamination of diethyl [(dimethylamino)methylene]malonate with arylhydrazines followed by base-catalyzed cyclization of the intermediate hydrazones.