Efficient methodology for the synthesis of unrecorded series of heterocycles based indolo[2,3-b] quinoxaline sub-structure is reported. Indolo[2,3-b] quinoxaline heterocycles have been synthesized by employing ethyl 3-(6H-indolo[2,3-b]quinoxalin-6-yl)propanoate as starting material. The precursor -H-indolo[2,3-b]quinoxalin-6-yl)propanehydrazide 3 was synthesized by reaction of ethyl 3-(6H-indolo[2,3-b]quinoxalin-6-yl)propanoate  with hydrazine in refluxing ethanol.   

The structures of synthesized compounds were confirmed on the basis of their elemental analyses and spectral results (IR, MS, 1H and 13C NMR). 

Acknowledgements: We thank Assiut University, Assiut, Egypt for financial support.

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