An Extraction of the Isatin from the &lt;i&gt;Couroupita guianesis&lt;/i&gt; (Cannon Ball Tree) and a Novel Synthesis of the N,N'-(2-oxo-3'H-spiro[indoline-3,2'-[1,3,4]thiadiazole]-3',5'-diyl]diacetamidefrom the Isatin
International letters of chemistry, physics and astronomy