Synthesis of certain 3-alkoxy-1-β-D-ribofuranosylpyrazolo[3,4-<i>d</i>]pyrimidines structurally related to adenosine, inosine and guanosine
作者:Jack D. Anderson、N. Kent Dalley、Ganapathi R. Revankar、Roland K. Robins
DOI:10.1002/jhet.5570230651
日期:1986.11
Several 3-alkoxysubstituted pyrazolo[3,4-d]pyrimidine ribonucleosides structurally related to adenosine, inosine and guanosine have been prepared by the direct glycosylation of preformed aglycon precursor containing a 3-alkoxy substituent. Ring closure of 5(3)-amino-3(5)-ethoxypyrazole-4-carboxamide (6b) with either formamide or potassium ethyl xanthate gave 3-ethoxyallopurinol (7b) and 3-ethoxy-6-thioxopyrazolo[3
在结构上与腺苷,肌苷和鸟苷相关的几种3-烷氧基取代的吡唑并[3,4- d ]嘧啶核糖核苷已经通过预先形成的含有3-烷氧基取代基的糖苷配基前体的直接糖基化作用而制备。5(3)-氨基-3(5)-乙氧基吡唑-4-羧酰胺(6b)与甲酰胺或乙基黄原酸钾的闭环得到3-乙氧基铝嘌呤醇(7b)和3-乙氧基-6-thioxopyrazolo [3,4- d ]-嘧啶-4(5 H,7 H)-一(10)。10的甲基化得到相应的6-甲硫基衍生物15。5(3)-甲氧基吡唑-4-羧酰胺(6a)与甲酰胺一起得到3-甲氧基铝嘌呤醇(7a)。用乙酸甲form提供的4-氨基-3-甲氧基吡唑并[3,4- d ]嘧啶(4)处理5(3)-氨基-3(5)-甲氧基吡唑-4-腈(5a)。在三氟化硼醚化物的存在下,7b与1 - O-乙酰基-2,3,5-三-O-苯甲酰基-D-呋喃呋喃糖进行高温糖基化反应,得到N-1和N-2糖基的2:1混合物