A compound selected from the group consisting of: (3-chloro-4-[(5-chloro-2-[(2- chlorophenyl)methyl]oxy}phenyl)carbonyl]amino}phenyl)acetic acid; 4-[(5-chloro-2-[(phenylmethyl)oxy]phenyl}carbonyl)amino]phenyl}acetic acid; 3-chloro-4-[(5-chloro-2-[(phenylmethyl)oxy]phenyl}carbonyl)amino]phenyl}acetic acid; (3-chloro-4-[(5-chloro-2-[(3- chlorophenyl)methyl]oxy}phenyl)carbonyl]amino}phenyl)acetic acid; 4-[(2-[(phenylmethyl)oxy]phenyl}carbonyl)amino]phenyl}acetic acid; (4-[(5-chloro-2-[(3-chlorophenyl)methyl]oxy}phenyl)carbonyl]amino}-2- fluorophenyl)acetic acid; 3-chloro-4-[(2-[(phenylmethyl)oxy]phenyl}carbonyl)amino]phenyl}acetic acid; (3-chloro-4-[(2-[(3-chlorophenyl)methyl]oxy}phenyl)carbonyl]amino}phenyl)acetic acid; 4-[(2-chloro-6-[(phenylmethyl)oxy]phenyl}carbonyl)amino]phenyl}acetic acid; (4-[(2-chloro-6-[(3-chlorophenyl)methyl]oxy}phenyl)carbonyl]amino}phenyl)acetic acid; 4-[(5-chloro-2-[(phenylmethyl)amino]phenyl}carbonyl)amino]phenyl}acetic acid; (4-[(5-chloro-2-[(3-chlorophenyl)methyl]amino}phenyl)carbonyl]amino}phenyl)acetic acid; and (4-[(5-chloro-2-[(2-chlorophenyl)methyl]amino}phenyl)carbonyl]amino}phenyl)acetic acid, or pharmaceutically acceptable salts thereof, pharmaceutical compositions comprising such compounds and the use of such compounds in medicine.