Synthesis of New tert‐Butyl‐ and Bromo‐functionalized [1,2,4]Triazino [5,6‐b]indole‐3‐thiols and Indolo[2,3‐b]quinoxalines

In the present investigation, the synthesis of a series of structurally new and interesting tert‐butyl‐ and bromo‐functionalized 1,2,4]triazino5,6‐b ]indoles ( 6a – f ) and indolo2,3‐b ]quinoxalines ( 8a – f ) has been achieved, involving the condensation reaction of 7‐bromo‐5‐tert‐butylisatins ( 4a – f ) with thiosemicarbazide ( 5 ) and benzene‐1,2‐diamine ( 7 ). The substrates 4a – f were prepared through bromination reaction of 5‐tert‐butylisatin ( 3 ) with NBS in PEG‐400 followed by alkylation reaction. The molecular structures of these newly synthesized compounds were elucidated on the basis of their elemental analyses and spectral data.