Synthesis of new thienotriazolopyrimidine and thienopyrimidotetrazine derivatives from bifunctional intermediates

Abstract

New compounds containing the thienotriazolopyrimidine and thienopyrimidotetrazine skeleton are prepared from the bifunctional intermediates 2,3-diamino-5,6-dimethylthieno [2,3-d]pyrimidin-4(3H)-one derivatives 13-17. The 2,pyrimidin-4(1H)-one derivatives 8-12 are also prepared.J. Heterocyclic Chem., 38, 973 (2001).For a long time, our research group has been interested in the synthesis of heterocyclic condensed derivatives, with the aim of evaluating their pharmacological activity, such as analgesic, anti-inflammatory [1-6] and anti-convulsive [7].In recent works, we described the preparation of 3-amino-2-thioxothieno[2,3-d]pyrimidinone [1,8] and of 3-amino-2-phenylaminothieno[2,3-d]pyrimidinone derivatives [7] which are versatile intermediates of bridgehead nitrogen polyheterocycles for the presence of two adjacent reactive functional groups. Through these intermediates, we obtained thiazolothienopyrimidines, thienopyrimidothiadiazoles, thienopyrimidothiadiazines, thienopyrimidotetrazines and thienotriazolopyrimidines [1][2][3][4][5][6][7][8][9].In this work, we report the synthesis of new N3-substituted-2-thioxothieno The reaction of the isothiocyanate 1 [10] in dichloromethane at room temperature with an ammonium hydroxide solution, with propylamine or methoxycarbonylhydrazine gave the derivatives 2, 5, and 7, respectively.The 2-thioxo derivatives 8-11 were obtained from compounds 2, 4 [11], 5, and 7, respectively, by refluxing in an ethanolic potassium hydroxide solution, followed by acidification of the aqueous suspension of the separated solids. Compounds 8 and 11 are identical with those obtained by other synthetic routes [12,13]. Compound 12 was obtained from the isothiocyanate 1 with ethylenediamine under the same experimental conditions adopted for the synthesis of derivatives 2, 5, and 7. By reaction of compounds 2 and 3 [13] with hydrazine hydrate were prepared the 2,3-diamino derivative 13 and the 2-methylamino derivative 15, respectively. The 2-amino-3-methylamino derivative 14 was 973

Synthesis of Certain New Thieno[2,3-d] pyrimidines as Potential Antitumor and Radioprotective Agents

“…The antitumor and radioprotective activities of some thiourea derivatives [31] led us to synthesize some thiophene derivatives containing thiourea moieties. Thus, reaction of 2-isothiocyanato derivative 3 with some nitrogen nucleophiles such as methylamine [32], butylamine, phenyl hydrazine and hydrazine hydrate [30] afforded the corresponding thiourea derivatives 7-10, respectively (Scheme 2). When compounds 3 and 4 were allowed to react with ethanolamine, the corres-…”

Polycyclic systems with the pyridopyrimidine and pteridine nuclei

“…Циклоконденсація гідразину 142і з ортоетерами 143 в оцтовій кислоті була використана для побудови конденсованої тетразинової системи 144 [78,83] (схема 40).…”