Adenosine 5'-monophosphate activated protein kinase (AMPK) has emerged as a major potential target for novel antidiabetic drugs. We studied the structure of 2-chloro-5-((Z)-((E)-5-((5-(4,5-dimethyl-2-nitrophenyl)furan-2-yl)methylene)-4-oxothiazolidin-2-ylidene)amino)benzoic acid (PT-1), which attenuates the autoinhibition of the enzyme AMPK, for the design and synthesis of different benzothiazoles with potential antidiabetic activity. We synthesized several structurally related benzothiazole derivatives that increased the rate of glucose uptake in L6 myotubes in an AMPK-dependent manner. One compound, 2-(benzo[d]thiazol-2-ylmethylthio)-6-ethoxybenzo[d]thiazole (34), augmented the rate of glucose uptake up to 2.5-fold compared with vehicle-treated cells and up to 1.1-fold compared to PT-1. Concomitantly, it elevated the abundance of GLUT4 in the plasma membrane of the myotubes and activated AMPK. Subcutaneous administration of 34 to hyperglycemic Kuo Kondo rats carrying the Ay-yellow obese gene (KKAy) mice lowered blood glucose levels toward the normoglycemic range. In accord with its activity, compound 34 showed a high fit value to a pharmacophore model derived from the PT-1.

The production of fermentable sugars from renewable sources is a challenge. An attempt was made to exploit glycogen as a potential feedstock for the production of glucose. The microwave-assisted acidic hydrolysis was applied for glycogen decomposition for the first time. The optimal conditions for the hydrolysis reaction (yield of glucose -62 wt.%) were identified: microwave irradiation time -10 min and concentration of acid -1 M HCl. Microwave irradiation has dramatically reduced the reaction time from more than 6 h (at 80 uC under an oil bath) to 10 min. 13 C NMR spectroscopy was employed to monitor the progress of the hydrolysis reaction. HPLC analysis was employed to evaluate the yield of glucose. Thus, the viability of the use of glycogen as an economically and environmentally benign precursor to the production of glucose has been demonstrated.

Adenosine monophosphate-activated protein kinase (AMPK) has been identified as one of the major targets for antidiabetic drugs. This study describes two AMPK-activating agents 2-(benzo[d]thiazol-2-ylmethylthio)-6-ethoxybenzo[d]thiazole and 2-(propylthio)benzo[d]thiazol-6-ol, that increase the rate of glucose uptake in L6 myotubes and also augment glucose-stimulated insulin secretion in INS-1E β-cells and rat islets. We believe that such unique bi-functional compounds can be further used for the development of a new class of antidiabetic drugs.