Reactions of 2H??3, 1??benzoxazine??2, 4??(1H) dione (isatoic anhydride) with anions of 1, 4??dihydro??5H??pyrazol??5??ones: Synthesis of pyrazolo [5, 1??b] quinazolin??9?? …

JC Sircar, T Capiris, SJ Kesten

Index: Sircar, Jagadish C.; Capiris, Thomas; Kesten, Stephen J. Journal of Heterocyclic Chemistry, 1981 , vol. 18, p. 117 - 121

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Citation Number: 10

Abstract

Abstract Reactions of 2H-3, 1-benzoxazine-2, 4-(1H) dione (isatoic anhydride)(1) with anions of 1, 4-dihydro-5H-pyrazol-5-ones (2) gave pyrazolo [5, 1-6] quinazolin-9-ones (3) via the nucleophilic attack of the anion 2b rather than 2a. However, in the case of 5- methoxyisatoic anhydride (10c), both products 3e and 11c were obtained. A new synthetic method of preparation of 5-(alkylthio)-2-aminobenzoic acids (18) was described. These ...