Novel derivatives of ISO-1 as potent inhibitors of MIF biological function.

A series of novel 1,2,4-oxadiazole, phthalimide, amide and other derivatives of ISO-1 were synthesized and probed for inhibition of macrophage migration inhibitory factor (MIF) activity. Several compounds inhibited MIF enzymatic activity at levels better than ISO-1. Of note, compounds 7, 22, 23, 24, 25 and 27 inhibited the spontaneous secretion/release/recognition of MIF from freshly isolated human peripheral blood mononuclear cells and, more importantly, inhibited the MIF-induced production of interleukin-6 (IL-6) and/or interleukin-1beta (IL-1beta) significantly better than ISO-1.