Identification of novel benzimidazole derivatives as highly potent AMPK activators with anti-diabetic profiles.

Diabetes is a global healthcare problem that affects more than 400 million people worldwide. Treatment for type 1 and 2 diabetes is expected by targeting adenosine monophosphate activated protein kinase, AMPK, a well-known master regulator of glucose. Many pharmaceutical companies have tried to identify AMPK activators but few direct AMPK activators with high potency for the ß2-AMPK isoform, which is important for glucose homeostasis, have been found. In addition, their chemical structure is limited to benzimidazole or indole derivatives bearing an aromatic substituent at the C5 position of the core structure. We describe herein our efforts to identify novel benzimidazole derivatives that directly activate the ß2-AMPK isoform. Our newly designed activator 14d bearing a 1-amino indanyl moiety at the C5 position of the core exhibited high in vitro potency and good pharmacokinetic profiles. A single oral dosing of 14d showed dose-dependent activation of AMPK and blood-glucose-lowering effects was observed in a diabetic animal model. In addition, chronic AMPK activation with 14d led to dose-dependent reduction in HbA1c of the animal model.

Identification of a novel benzimidazole derivative as a highly potent NPY Y5 receptor antagonist with an anti-obesity profile.

Optimization of HTS hit 1 for NPY Y5 receptor binding affinity, CYP450 inhibition, solubility and metabolic stability led to the identification of some orally available oxygen-linker derivatives for in vivo study. Among them, derivative 4i inhibited food intake induced by the NPY Y5 selective agonist, and chronic oral administration of 4i in DIO mice caused a dose-dependent reduction of body weight gain.

Subtleties in GPCR drug discovery: a medicinal chemistry perspective.

Therapeutic effects through G protein-coupled receptors (GPCRs) are promoted by a full agonist, partial agonist, neutral antagonist or inverse agonist. Dramatic change of function such as from a neutral antagonist to a full agonist with minimal variation of ligand structure is a phenomenon that medicinal chemists often encounter. This is also influenced by a change of assay format. The subtle nature of structure-function relationships is difficult to grasp unless carefully considered from both chemistry and assay perspectives. In this article we discuss the subtle aspects of GPCR drug discovery from the medicinal chemistry perspective.

Rh(I)-catalyzed asymmetric synthesis of 3-substituted isoindolinones through CO gas-free aminocarbonylation.

A highly efficient and accessible synthesis of chiral 3-substituted isoindolinone frameworks is described. The synthesis involved the Rh(I)-catalyzed asymmetric arylation of boronic acids to 2-halobenzaldimines and the subsequent Rh(I)-catalyzed intramolecular aminocarbonylation of the resulting 2-halobenzylamines using an aldehyde as the carbonyl source. The method tolerates a variety of functional groups, yielding isoindolinone derivatives in moderate to high yields with high ee-values. In addition, two Rh(I)-catalyzed transformations could be efficiently accomplished in a one-pot sequence to give chiral isoindolinones by the simple addition of a ligand and an aldehyde after the Rh(I)-catalyzed asymmetric arylation.

Swallow syncope, a case report and review of the literature.

Swallow syncope is a relatively rare syndrome that is treatable when diagnosed. A 66-year-old woman was referred to the department of cardiology because she had been suffering from recurrent syncopal attacks associated with swallowing. An ambulatory electrocardiogram revealed atrial and ventricular asystoles immediately after swallowing soup or tea that were reproducible (max. RR 3.5 s). An electrophysiological study did not detect sinus nodal or atrioventricular nodal dysfunction. The patient had no underlying esophageal disease or cardiac disorder. The patient's symptoms resolved after permanent pacemaker implantation. This report reviews the diagnosis, mechanism and management of swallow syncope.