| 摘要 |
<p>A process for converting a xanthine derivative represented by general formula (I) [compound (I)], (wherein R?1 and R2¿ are the same or different from each other and each represents hydrogen or hydroxy-, oxo- or unsubstituted lower alkyl) into another xanthine derivative represented by general formula (II) [compound (II)], (wherein R?3 and R4¿ are the same or different from each other and each represents hydrogen or hydroxy-, oxo- or unsubstituted lower alkyl; R?5 and R6¿ are the same or different from each other and each represents hydrogen, hydroxy or oxo, provided when both of R?5 and R6¿ are hydrogen, at least one of R?3 and R4¿ is hydroxy- or oxo-substituted lower alkyl; and X and Y represent both hydrogen or they are combined together to represent a single bond) in the presence of an enzyme source which catalyzes the hydroxylation or carbonylation of compound (I) into compound (II).</p> |
