Patent ID: 8765920

Claim:
A method of chemoselectively modifying a moiety containing the amino acid tyrosine, the method comprising the step of reacting a compound of Formula X with a compound of Formula XI to provide a compound of Formula XII, thereby modifying the moiety containing the amino acid tyrosine: wherein: W is independently a direct bond or is O; R 3 is independently hydrogen, halogen, carboxyl, cyano, nitro, amino, substituted or unsubstituted alkyl, substituted or unsubstituted thioalkyl, perfluoroalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroaryloxy; substituted or unsubstituted alkylaryl, or substituted or unsubstituted alkylheteroaryl, or two R 3 groups form a cyclic or heterocyclic ring, wherein each R 3 is optionally independently substituted with 1 to 3 groups selected from halogen, carboxyl, cyano, nitro, amino, alkyl, alkenyl, alkynyl, perfluoroalkyl, thioalkyl, alkoxy, aryloxy, aryl, alkylaryl, heteroaryl, and alkylheteroaryl; L is independently H, N 3 , CH 3 , C≡CH, C≡CN 3 , CH═CHN 3 , CH 2 CH 2 N 3 , O(CH 2 )N 3 , C 6 H 5 , COCH 3 , OCH 2 C≡CH, OCH 2 COCH 3 , OCOCF 3 , or X—[CH 2 CH 2 —Y] n —(CH 2 ) q —N 3 ; X and Y are each independently CH 2 , O, NH, S, NHCO or CONH; n and q are each independently an integer from 0 to 12; R 7 , R 8 and R 9 are each independently hydrogen, hydroxyl, amino, substituted or unsubstituted alkyl, substituted or unsubstituted thioalkyl, perfluoroalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkylaryl, substituted or unsubstituted alkylheteroaryl, or R 7 , R 8 and R 9 are in a tyrosine residue of a peptide or a protein.