1021298-90-7Relevant articles and documents
Fused pyrazino[2,3-b]indolizine and indolizino[2,3-b]quinoxaline derivatives; synthesis, structures, and properties
Bloch, Witold M.,Derwent-Smith, Stephanie M.,Issa, Fatiah,Morris, Jonathan C.,Rendina, Louis M.,Sumby, Christopher J.
, p. 9368 - 9375 (2011)
The synthesis of six new compounds incorporating either a pyrazino[2,3-b]indolizine or indolizino[2,3-b]quinoxaline core are reported in good yield (58-87%). The intermediates for the key cyclization reaction for one set of compounds (5a-c), with a sterically demanding 3,5-dimethylpyrazole group in the 5-position of the core, were found to be mono-substituted. These intermediates could be isolated and cyclized by heating under acid-catalyzed conditions. To further demonstrate the versatility of the chemistry, compounds 6a-c were synthesized in 58-68% yields. Compounds 5a-c are non-planar in solution and the solid-state, while 6a-c have close to planar conformations, pointing to weak hydrogen bonds between the acidic C-Hs and the adjacent azine nitrogen atoms. The cytotoxicity of the six newly synthesized and three previously prepared compounds was assessed against a human glioblastoma multiforme cell line.
