1	TGH	6-{[(S)-carboxy(hydroxy)methyl]amino}-7-hydroxy-L-tryptophan	1.000
2	TNQ	6-[(carboxymethyl)amino]-7-hydroxy-L-tryptophan	0.955
3	1TQ	6-(formylamino)-7-hydroxy-L-tryptophan	0.864
4	0AF	7-hydroxy-L-tryptophan	0.727