Alkylation of pyrimido[5′,4′:5,6]pyrido[3,2-b]indol-4-one derivatives

Article abstract of DOI:10.1007/s11172-008-0234-1

Alkylation of 11-benzyl-3,11-dihydro-4H-pyrimido[5′,4′:5,6] pyrido[3,2-b]indol-4-one with methyl iodide and methyl bromoacetate in DMF gave 3-alkylpyrimidopyridoindolones as the corresponding salts. The reaction in acetone in the presence of K₂CO₃ yielded 3,6-disubstitution products. Alkylation with DMF dimethyl acetal gave a mixture of the 3- and 6-alkylpyrimidopyridoindol-4-one bases. The structure of 4-oxo-4,6-dihydro-3H-pyrimido-[5′,4′:5,6]pyrido[3,2-b]indol-11-ium chloride (3b) was proved by X-ray diffraction analysis.