The Hydrolysis of Alkyl-3'Uridyl Phosphate or Acetate Esters Can be Used to Estimate the pKa of Neopentyl Alcohol
Keywords:
Phosphate and Acetate Hydrolysis, NeopentanolAbstract
The research project aim is to determine the pKa of neopentanol alcohol because it has been used in many biological models as a leaving group. The pKa of neopentanol alcohol can be obtained by measuring the observed rate for compound 1 under identical conditions to that reported for a similar series of alkyl uridyl phosphate diesters. The pKa of neopentyl alcohol was derived from the reported Brønsted plot for the hydroxide-catalyzed hydrolysis of alkyl uridyl phosphate diesters and the observed rate constant for uridine 3´-neopentyl phosphate 1. As a result, the best estimate for the pKa of neopentanol alcohol can established from this work. The corresponding pKa of neopentyl alcohol from the observed rate of the hydroxide-catalyzed hydrolysis of 1 is 17.3, which is significantly greater than the value of 15.5 used in earlier reports. This new value can be used now to estimate a better half- life for pH-independent DNA cleavage. This allows us to use correctly the neopentyl group as a mimicked model for biological systems such as that in DNA cleavage
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