Synthesis and evaluation of disubstituted N1- and N3-imidazolidin-2-ones acting as potential immunosuppressive agents.

New N1-mono and N1, N2-disubstituted imidazolidin-2-one with a significant immunosuppressive activity have been discovered. Among the 17 synthesized and tested compounds, five of them showed maximal inhibition of proliferation of concanavallin A (Con A)- stimulated splenocytes at 90 microM, identical to that obtained with cyclosporin A (CsA) at 5 microM, an optimal concentration.