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 Couroupita guianesis 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.
The solubility of isatin in different solvents was studied by a gravimetrical method from (298.15 to 318.15) K under atmospheric pressure and the solubility data were correlated against temperature. The solvents selected for the present study are: water, methanol, ethanol, 1-butanol, dichloromethane, dichloroethane, chloroform and carbon tetra chloride. Among chlorinated solvents, solubility is observed to be maximum in 1, 2-dichloroethane and minimum in dichloromethane whereas in alcohols, maximum solubility is observed in methanol. In water, solubility is found to be minimum. Further, some thermodynamic parameters such as Gibb’s energy (ΔGsol), heat of solution (ΔHsol) and entropy of solution (ΔSsol) have also been evaluated.
3
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
An efficient method for the preparation of 6,7-dimethoxyisatin and its derivatives was developed with good yield by using Preyssler-type heteropolyacid (HPA) as acid catalyst under green conditions. The comparison between Keggin type heteropolyacids, H3[PW12O40], H4[SiW12O40] and H4[SiMo12O40], H3[PMo12O40] and mineral acids with Preyssler's anion shows that the latter possess better catalytical activity than the other heteropolyacids and no degradation of the structure was observed.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.