Glucose analogs

Nine other glucose analogs were systematically studied with yeast and mammalian brain hexoklnases (79). Five of these analogs exhibited substrate activity with the yeast isoenzyme, and two were found to be competitive inhibitors. Two of the alternate substrates were studied with the mammalian enzyme, but no significant differences were found. 

The x-ray structure for yeast hexokinase is also available. Thus, glucose analogs are now being used to elucidate minute details of the catalytic mechanism. Recently D- lose was used in crystallographic work to show that the 6-hydro ethyl group of the natural substrate is necessary for substrate-induced closure of the active-site cleft (81 ). This induced closure, which is observed with glucose binding (82), is believed to be a part of the induced fit mechanism postulated for hexokinase (83) ... 

T. Ido, C.N. Wan, V. Casella, J.S. Fowler, A.P. Wolf, M. Reivich, D.E. Kuhl, Labeled 2-deoxy-D-glucose analogs—F-18-labeled 2-deoxy-2-fluoro- o-glucose, 2-deoxy-2-fluoro- D-mannose and C-14-2-deoxy-2-fluoro- o-glucose, J. Label. Compds Radiopharm. 14 (1978) 175-183. 

The glucose analog, 3-deoxy-3-C-methylene-D-nfco-hexose (102) is a substrate of a D-xylose isomerase. The efficient synthesis from 3-deoxy-3-C-methylene-glucofuranose (101 prepared by the classical method according to [92]) was described recently (O Scheme 44) [93]. 

Ido, T., Wan, C. N., Casella, V., et al. (1978) Labeled 2-deoxy-D-glucose analogs. Fluorine-18-labeled 2-deoxy-2-fluoro-D-glucose, 2-deoxy-2-fluoro-D-mannose and 14C-2-deoxy-2-fluoro-D-glucose. J Labeled Com. Radiopharm. 14, 175-183. 

Autoradiographic Tracers for Neuronal Activation Studies Ex vivo autoradiography is also commonly used with the glucose analog [ C] 2-dcoxyglucose (2-DG) to provide maps of the metabolic demands of neurons (Sokoloff et al. 1977). [ C]2-DG is a substrate for facilitated glucose carriers in the blood-brain barrier... 

Keywords Glycogen phosphorylase Glucose Glucose analog inhibitors NIDDM Sugar-derived heterocycles... 

The recent advances, especially during last few years, in different heterocyclic glucose analog inhibitors (GAIs) and their precursors are briefly discussed in this chapter, including their biological activities against this very important enzyme GP, from different perspectives. 

Catalytic site, which binds substrates GIP and glycogen, and the inhibitor glucose and glucose analogs (GA)... 

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