A phosphonate nucleotide compound having antiviral activity and is useful for an orally available and highly safe antiviral agent, which is represented by the following formula (I): ##STR1## wherein R.sup.1 represents hydrogen, a C.sub.1 -C.sub.6 alkoxy, a halogen-substituted C.sub.1 -C.sub.4 alkoxy, halogen, amino, or nitro; R.sup.2 and R.sup.3 independently represent hydrogen, a C.sub.1 -C.sub.22 alkyl, an acyloxymethy, an acylthioethyl, or a halogen-substituted ethyl; R.sup.4 represents hydrogen, a C.sub.1 -C.sub.4 alkyl, a C.sub.1 -C.sub.4 hydroxyalkyl, or a halogen-substituted C.sub.1 -C.sub.4 alkyl; and X represents carbon or nitrogen.
一种具有抗病毒活性并且适用于口服的高安全性抗病毒剂的
膦酸核苷化合物,其
化学式如下(I):其中R.sup.1代表氢、C.sub.1-C.sub.6烷氧基、卤素取代的C.sub.1-C.sub.4烷氧基、卤素、
氨基或硝基;R.sup.2和R.sup.3独立地代表氢、C.sub.1-C.sub.22烷基、酰氧甲基、酰
硫乙基或卤素取代的乙基;R.sup.4代表氢、C.sub.1-C.sub.4烷基、C.sub.1-C.sub.4羟基烷基或卤素取代的C.sub.1-C.sub.4烷基;X代表碳或氮。