Production of new amilorides as potent inhibitors of mitochondrial respiratory complex I.
Amilorides, well-known inhibitors of Na(+)/H(+) antiporters, have also shown to inhibit bacterial and mitochondrial NADH-quinone oxidoreductase (complex I). Since the membrane subunits ND2, ND4, and ND5 of bovine mitochondrial complex I are homologous to Na(+)/H(+) antiporters, amilorides have been thought to bind to any or all of the antiporter-like subunits; however, there is no direct experimental evidence in support of this notion. Photoaffinity labeling is a powerful technique to identify the binding site of amilorides in bovine complex I. Commercially available amilorides such as 5-(N-ethyl-N-isopropyl)amiloride are not suitable as design templates to synthesize photoreactive amilorides because of their low binding affinities to bovine complex I. Thereby, we attempted to modify the structures of commercially available amilorides in order to obtain more potent derivatives. We successfully produced two photoreactive amilorides (PRA1 and PRA2) with a photolabile azido group at opposite ends of the molecule.
a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kyoto , Japan.
Masatoshi
M
Murai
Sayako
S
Habu
Sonomi
S
Murakami
Takeshi
T
Ito
Hideto
H
Miyoshi
D000584:Amiloride / Q000031:analogs & derivatives / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D060326:Chemistry Techniques, Synthetic; D042967:Electron Transport Complex I / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D019920:Photoaffinity Labels; D013329:Structure-Activity Relationship
D004791:Enzyme Inhibitors; D019920:Photoaffinity Labels; C013407:benzamil; D000584:Amiloride; D042967:Electron Transport Complex I
NADH-quinone oxidoreductase (complex I); amilorides; mitochondria; structure–activity relationship