What does N-TLCK stand for?

N-TLCK stands for N, alpha-tosyl-L-lysine chloromethyl ketone

This definition appears rarely

affinity of Chtr1 to inhibitors containing Arg at P1 position. N-alpha-tosyl-L-lysine chloromethyl ketone (TLCK), Chtr1 in 0. 1 M Tris-HCl, pH 7.