Oxygen chiral phosphate

II. Methods for Syntheses and Configurational Analyses of Oxygen Chiral Phosphate and... 

Methods based on the effects of the quadrupolar O nucleus (/ = f) and the 0 nucleus (7 = 0) on the P NMR spectral properties of the isotopically labeled P nucleus are now the only methods used to ascertain the configurations of tetrahedral phosphorus atoms in oxygen chiral phosphate esters. The chemical... 

The first application of this 0 effect for determining the configuration of an oxygen chiral phosphate ester was the author s determination of the configuration of diastereomeric samples of cyclic [, 0]dAMP, the chiral substrate for studying the stereochemical consequences of the reverse reaction catalyzed by adenylate cyclase (formation of cyclic AMP from ATP), and of the hydrolysis reaction catalyzed by 3, 5 -cyclic nucleotide phosphodiesterase (25) (see Fig. 

Whereas the 0 effect on P NMR chemical shifts is sufficient for determining the configurations of chirally labeled samples of prochiral phosphorus atoms in a diastereomeric environment, additional use of the quadrupolar effect of O on P NMR resonances is required for configurational analyses of oxygen chiral phosphate monoesters. The basic strategy for the configurational analyses of phosphate monoesters is the same, i.e., the enantiomeric center in the monoester must be converted to a diastereomeric center in a cyclic phosphodiester so that... 

The first account of the synthesis of an oxygen chiral phosphate monoester was reported in 1978 by Knowles and co-workers (Abbott et ai, 1978, 1979). This ester, a diastereomer of l-phospho-(5)-1,2-propanediol, was selected as the synthetic target because the general method of configurational analysis that Knowles devised for monoesters was based on the ability to assign the configuration of the diastereomers at phosphorus of this particular phosphate monoester. The chemical steps in this synthesis are shown in Fig. 1. Briefly, [ OJPOCls, prepared in hi yield from and... 

Stereochemical Studies Using Oxygen Chiral Phosphate Esters and P-NMR Methods of... 

Methods have been developed for the synthesis of essentially any oxygen chiral phosphate ester of biological importance, and the P-NMR methods described and illustrated in this chapter provide a convenient method for determining their configurations and elucidating the stereochemical consequences of enzyme-catalyzed phosphoryl and nucleotidyl transfer reactions. 

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