N4-Substituted derivatives of HPMPC were synthesized in four-step synthesis which included treatment of 4-methoxypyrimidin-2(1H)-one (1) with (S)-[(trityloxy)methyl]oxirane in DMF. Condensation of intermediary 1-[2-hydroxy-3-(trityloxy)propyl]-4-methoxypyrimidin-2(1H)-one (2) with (diisopropoxyphosphoryl)methyl tosylate in the presence of sodium hydride resulted in fully protected 4-methoxypyrimidin-2(1H)-one derivative 3 which gave on reaction with an appropriate primary amine in dioxane N4-substituted products 4a-4i. The reaction with bromotrimethylsilane simultaneously cleaved the trityl group and deprotected the phosphonate residue and gave the title HPMP analogues substituted at the cytosine amino group in position N4 5a-5i. Compound 4j was prepared from 4-methoxypyrimidin-2(1H)-one (1) by reaction with cyclopropylamine in dioxane. The intermediary 4-(cyclopropylamino)pyrimidin-2(1H)-one (6) then reacts with (S)-[(trityloxy)methyl]oxirane in DMF. Fully protected phosphonate 4j and its deprotected counterpart 5j was obtained by the same sequence of reactions as in the case of compounds 5a-5i.
HPMPC的N^4-取代衍生物通过四步合成制备,包括在DMF中用(S)-[(三苯甲氧基)甲基]环氧乙烷处理4-甲氧基嘧啶-2(1H)-酮(1)。中间体1-[2-羟基-3-(三苯甲氧基)丙基]-4-甲氧基嘧啶-2(1H)-酮(2)与(diisopropoxyphosphoryl)甲基对甲苯磺酸酯在氢化钠存在下缩合,得到全保护的4-甲氧基嘧啶-2(1H)-酮衍生物3,与适当的一级胺在二氧六环中反应得到N^4-取代产物4a-4i。与溴三甲基硅烷反应同时裂解三苯甲基基团和去保护磷酸酯残基,得到在胞嘧啶氨基N^4位置取代的标题HPMP类似物5a-5i。化合物4j由4-甲氧基嘧啶-2(1H)-酮(1)与环丙胺在二氧六环中反应制备。中间体4-(环丙胺基)嘧啶-2(1H)-酮(6)然后与(S)-[(三苯甲氧基)甲基]环氧乙烷在DMF中反应。全保护磷酸酯4j及其去保护对应物5j通过与化合物5a-5i相同的反应序列获得。