Collection of Czechoslovak Chemical Communications · 1984 · 11 citations · 0 references
Natural SciencesChemistryMedicinal ChemistryBioorganic ChemistryOrganic ChemistrySynthetic Medicinal ChemistryHeterocycle SynthesisHeterocyclic ChemistryOrganic SynthesisFuran ChemistryIndole ChemistryIndole DerivativesIndole SynthesisMedicinal Chemistry ApplicationsPyrrole SynthesisTriazole ChemistryTriazole Synthesis
The new 1,2,4-triazolo[3''', 4''':6'', 1'']-1,2,4-triazino[4'', 5'':4,5]furo[3,2- b ]indoles V and 1-acetyl-9 H -pyrrolo[2',3':4,5]furo[3,2- b ]indole ( IX ) were prepared from 1,9-dihydropyrrolo[2',3':4,5]furo[3,2- b ]indole-2-carboxhydrazide I and 2-(2-nitrophenyl)-4 H -furo[3,2- b ]pyrrole-5-carboxylic acid, respectively. Compound I gave with triethyl orthoformate or with triethyl orthoacetate 1,2-dihydro-1,2,4-triazino[4'',5'':1',5']pyrrolo[2',3':4,5]furo[3,2- b ]indol-1-one or its methyl analogue II . Substances II afforded with phosphorus pentasulfide thiones III reacting with hydrazine to furnish IV . Cyclization of the latter with triethylorthoformate or orthoacetate led to V . Compounds II and III can also be obtained by a deoxygenative cyclization of VI and VII with triethyl phosphite.