Patent ID: 7625838

Claim:
A method for affinity chromatography, comprising the step of selectively adsorbing IgG, fragments thereof and/or complexes involving IgG or fragments thereof on a chromatographic adsorbent, using a compound comprising the following formula and its corresponding enol-form, wherein X represents O, S, or NH; R 1 represents H, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl, Ar, —C(O)NHR 3 , —C(O)—R 3 or halo; R 2 represents H, C 1-3 alkyl or halo; R 3 represents H, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkoxy-C 1-6 alkyl or Ar; n represents 0, 1, 2 or 3; Y represents a carrier; Ar represents a C 6-10 aryl group, which group is optionally substituted by one or more substituents selected from —OH, cyano, halo, nitro, C 1-6 alkyl and alkoxy.