General Synthesis of 1-Aryl-6-azaisocytosines and Their Utilization for the Preparation of Related Condensed 1,2,4-Triazines
oleh: František Zálešák, Jan Slouka, Jakub Stýskala
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2019-10-01 |
Deskripsi
A simple general synthesis of 1-aryl-6-azaisocytosine-5-carbonitriles <b>4</b> is described. This method is based on coupling diazonium salts with cyanoacetylcyanamide <b>2</b> and then cyclization of the formed 2-arylhydrazono-2-cyanoacetylcyanamides <b>3</b>. The 6-azaisocytosines <b>4</b> were studied with respect to tautomeric equilibrium and the transformation of functional groups, and used in the synthesis of the condensed heterocyclic compounds: Purine isosteric imidazo[2,1-<i>c</i>]-[1,2,4]triazine <b>8</b> and the 1,2,4-triazino[2,3-<i>a</i>]quinazolines <b>9</b>−<b>12</b>.