| 摘要 |
<p>Cpds. (I) useful as analgesics, diuretics and uric acid inhibitors are prepd. in high yields by reacting (II) with R3SH then cyclising the product, without isolation, with ethyl ortho formate or esp. with formamide. (where R1 and R2 are H, alkyl, aryl, aralkyl, cycloalkyl, acyl, arylsulphonyl and heterocyclyl and R3 is H, alkyl, aryl, aralkyl, cycloalkyl or heterocyclyl).</p> |
