Rahul R. Tripathi, Ratnamala P. Sonawane, An Extraction of the Isatin from the Couroupita guianesis (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, ILCPA Volume 15, International Letters of Chemistry, Physics and Astronomy (Volume 15)
https://www.scipress.com/ILCPA.15.119
Abstract:
    Isatins are synthetically versatile substrates, where they can be used for the synthesis of a large variety of Isatins and heterocyclic compounds. In this, the isatin were extracted from the floral material of<i> Couroupita guianesis</i> commonly known as an Cannon ball tree. After that, a novel heterocyclic spiro derivative having an IUPAC name N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesized , which may be used as raw material for drug synthesis. A spiro compound N,N’-(2-oxo-3’H-spiro[indoline-3,2’-[1,3,4] thiadiazole]-3’5’-diyl)diacetamide were synthesise by refluxing Isatin and thiosemicarbazone in ethanol and then on heating with acetic anhydride underwent to cyclization into intermediate that on acetylation of the NH and NH2 groups afforded the spiro compound.
Keywords:
    <i>Couroupita guianesis</i>, Isatin, Thiosemicabazone