| abstract |
The invention relates to a process for preparing phosphonoformates of the general formula I by reacting Phosphorigsaeuredialkylestern or mixtures of Phosphorigsaeuredialkylestern and Phosphorigsaeuredialkyl-trimethylsilyl, (RO) 2P O SiMe3, in the presence of hexamethyldisilazane with chloroformates to Phosphonoameisensuretriestern in the reaction mixture in the presence of ammonium chloride , HMDZ and trimethylchlorosilane be partially or completely dealkylated to bis-trimethylsilyl-phosphonoameisensureestern. By subsequent alkaline hydrolysis, the compounds I are obtained. In formula I R is alkyl of C1 to C6, cycloalkyl, benzyl or an alkali metal R1, R2, identical or different radicals, alkyl, Me3Si-, hydrogen, alkali metal, ammonium or substituted ammonium radical. The compounds possess selective antiviral properties. |