594859-32-2Relevant academic research and scientific papers
Synthesis of some new pyridothienopyrimidines and related [1,2,4]triazolopyridothienopyrimidines
Bakhite, E.A.,Abdel-Rahman, A.E.,Mohamed, O.S.,Thabet, E.A.
, p. 236 - 247 (2007/10/03)
3-Amino-4-phenyl-6-(2-thienyl)thieno[2,3-b]pyridine-2-carboxamide (3a) reacted with triethyl orthoformate to give the pyrimidinone derivative 4. Reaction of 4 with phosphorus oxychloride produced the corresponding 4-chloropyrimidine derivative 5 which underwent some nucleophilic displacements upon treatment with thiourea, morpholine or aniline to give the pyridothienopyrimidine derivatives 6, 8 and 9 respectively. Similarly, the reaction of 5 with hydrazine hydrate afforded 4-hydrazino-9-phenyl-7-(2-thienyl)pyrido[3',2':4,5]thieno[3,2-d]pyrimidine (10). The condensation of 3-amino-4-phenyl-6-(2-thienyl)thieno[2,3-b]pyridine-2-carbonitrile (3b) with triethyl orthoformate led to the methanimidate derivative 18 which upon treatment with hydrazine hydrate furnished 3-amino-3,4-dihydro-4-imino-9-phenyl-7-(2-thienyl)pyrido[3',2':4,5]thieno[3,2-d]pyrimidine (19). The compounds 10 and 19 were used as precursors for synthesizing the isomeric [1,2,4]triazolopyridothienopyrimidines via Dimroth rearrangements.
