Fluorescent bioprobes for visualization of puromycin-sensitive aminopeptidase in living cells.

Non-peptide, small-molecular, non-competitive inhibitors of puromycin-sensitive aminopeptidase (PSA), that is, 3-(2,6-diethylphenyl)-2,4(1H,3H)-quinazolinedione (PAQ-22, 3) and its 1N-methyl analogue (MPAQ-22 4), were structurally modified to afford fluorescent bioprobes, ANTAQ (5) and DAMPAQ-22 (6). The cellular localization of PSA could be visualized by the use of these fluorescent bioprobes.

Synthesis and mechanism of action of novel pyrimidinyl pyrazole derivatives possessing antiproliferative activity.

Pyrimidinyl pyrazole derivatives 1-4, prepared as a new scaffold of an anti-tumor agent, showed antiproliferative activity against human lung cancer cell lines and inhibited tubulin polymerization. Furthermore, it was found that compound 2 bound at the colchicine site on tubulin, but the tubulin binding pattern was different from that of colchicine. Here, we describe the synthesis of the derivatives and the differences of the action mechanism on tubulin polymerization inhibition between compound 2 and colchicine.

Novel non-steroidal/non-anilide type androgen antagonists with an isoxazolone moiety.

3-Substituted (Z)-4-(4-N,N-dialkylaminophenylmethylene)-5(4H)-isoxazolones and related compounds were designed and prepared as candidates for structurally novel androgen antagonists. Several compounds showed potent anti-androgenic activity as assessed by nuclear androgen receptor binding assay and growth inhibition assay using androgen-dependent Shionogi carcinoma cells SC-3. They were approximately 10--220 times more potent than flutamide in these assay systems.