The Hydrolysis of Alkyl-3'Uridyl Phosphate or Acetate Esters Can be Used to Estimate the pKa of Neopentyl Alcohol


  • Mohamed S. Sasi Department of Chemistry, Education Faculty, Misurata University, Misurata, Libya
  • Abdulfattah M. Alkherraz Department of Chemistry, Education Faculty, Misurata University, Misurata, Libya
  • Mohamed A. Elsirkasi Laboratory Department, Faculty of Medical Technology, Misurata, Libya


Phosphate and Acetate Hydrolysis, Neopentanol


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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