| Abstract
| - The main objectives of the present work were thesynthesis of the two cis diastereomers of 5,6-dihydroxy-5,6-dihydro-5-methyl-2‘-deoxycytidine and the kinetic study oftheir hydrolytic deamination. The preparation of the two glycols, two main•OH-mediated oxidation products of5-methyl-2‘-deoxycytidine, was achieved in two steps. The first one involvedthe synthesis of the two trans-(5R,6S)- and(5S,6R)-5-bromo-6-hydroxy-5,6-dihydro-5-methyl-2‘-deoxycytidine.In a subsequentstep, the bromohydrins were specifically converted into thecis-(5S,6S) and(5R,6R) diastereomersof 5,6-dihydroxy-5,6-dihydro-5-methyl-2‘-deoxycytidine, respectively,under slightly alkaline conditions. The resulting glycols were purified by reverse phase highperformance liquid chromatographyand characterized by extensive spectroscopy measurements including13C- and 1H-NMR analyses.Exact mass determination was inferred from high resolution fastatom bombardment massspectrometry measurements. Circular dichroism spectroscopyconfirmed the diastereomericrelationship existing between the pair of glycols. Kinetic studyof the deamination of the aboveglycols was carried out in phosphate buffer solutions (pH 7) at twodifferent temperatures (37 °Cand 25 °C) in order to determine the thermodynamic and kineticparameters of the reaction.
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