Synthetic receptors for neutral nitro derivatives

Different arylurea-based receptors with similar substitution pattern and one guanidine-based receptor were synthesised and studied concerning their binding capability towards the title functional group; specific binding of neutral nitro groups is revealed with relatively high binding constants in DMSO ranging from 470 to 1370 M−1 for urea and 730–990 M−1 for guanidine-based binding partners.