POTENT RETINOID SYNERGISTS WITH A DIPHENYLAMINE SKELETON

Abstract

4-[N-(5, 6, 7, 8-Tetrahydro-5, 5, 8, 8-tetramethyl-2-naphthyl)amino]benzoic acid (5) exhibited weak retinoidal and retinoid synergistic activities in HL-60 cell differentiation assay. N-Alkylation of 5 caused decrease or loss or differentiation-inducing activity, but enhanced the synergistic activity with a synthetic retinoid Am80 (2), as reflected in the potent synergistic EC₅₀ (SEC₅₀) values of DA023 (11, 1.6×10^-10 M) and DA113 (14, 1.4×10^-10 M) in the presence of 1.0×10^-10 M Am80 (2).