Photobiological properties of 1-(3'-hydroxypropyl)-4,6,8-trimethylfur

Discovery of furan and dihydrofuran-fused tricyclic benzo[d]imidazole derivatives as potent and orally efficacious microsomal prostaglandin E synthase-1 (mPGES-1) inhibitors: Part-1

This letter describes the synthesis and biological evaluation of furan and dihydrofuran-fused tricyclic benzo[d]imidazole derivatives as novel mPGES-1 inhibitors, capable of inhibiting an increased PGE₂ production in the disease state. Structure-activity optimization afforded many potent mPGES-1 inhibitors having <50 nM potencies in the A549 cellular assay and adequate metabolic stability in liver microsomes. Lead compounds 8l and 8m demonstrated reasonable in vitro pharmacology and pharmacokinetic properties over other compounds. In particular, 8m revealed satisfactory oral pharmacokinetics and bioavailability in multiple species like rat, guinea pig, dog and cynomolgus monkey. In addition, the representative compound 8m showed in vivo efficacy by inhibiting LPS-induced thermal hyperalgesia with an ED₅₀ of 14.3 mg/kg in guinea pig.

4-Hydroxymethyl-1,6,8-trimethylfuro[2,3-h]quinolin-2(1H)-one Induces Mitochondrial Dysfunction and Apoptosis upon Its Intracellular Oxidation

We investigated the mechanism of cell death induced by a furoquinolinone derivative, namely, 4-hydroxymethyl-1,6,8-trimethylfuro[2,3-h]quinolin-2(1H)-one (HOFQ), in the dark. Mitochondrial depolarization was found to be a causative event in HOFQ-induced apoptosis that was blunted either by replacing the 4-hydroxymethyl group with a methyl one, or by 4-methylpyrazole, an inhibitor of alcohol dehydrogenase (ADH). In vitro enzymatic assay demonstrated that HOFQ is a substrate of ADH. In isolated mitochondria HOFQ was without effect, whereas in the presence of ADH and NAD(+) it caused the opening of the permeability transition pore, indicating that HOFQ-oxidized products affect mitochondrial function directly. Finally, an analogue bearing the formyl group at the C-4 position mimicked all the effects exerted by HOFQ. In conclusion, these results suggest that the direct action on mitochondria of HOFQ-oxidized products are responsible for their cytotoxicity, which might be exacerbated, but hardly determined, by photodynamic action and/or binding to DNA.