Cartoon representation of the JAK3 (upper) with an overlay of 6-nitroquinoxaline derivatives (a) and quinoxalin-6-amine derivatives (b) and BTK (lower) with an overlay of 6-nitroquinoxaline derivatives (c) and quinoxalin-6-amine derivatives (d) in the binding cavity highlighting the interacting residues. Dotted lines show hydrogen bonding.