ChEBI: BNPS-skatole is a bromoindole that is 3H-indole in which the hydrogen at position 2 has been replaced by an (o-nitrophenyl)sulfanyl group and in which the hydrogens at position 3 have been replaced by a bromine and a methyl group. It is used particularly for the selective cleavage of tryptophanyl peptide bonds (cleavage occurs at peptide bonds after amino acids with available C(gamma)=C(delta) double bonds such as tryptophan, tyrosine, and histidine). It has a role as a reagent. It is an aryl sulfide, a C-nitro compound and a bromoindole.