Direct conversion to 2-phenyl-4-quinolones via a 4-alkoxyflavylium salt from a naturally occurring flavanone

✍ Scribed by Shingo Sato; Hironobu Kumagai; Shigeru Matsuba; Toshihiro Kumazawa; Jun-Ichi Onodera; Masanobu Suzuki

• Publisher: Journal of Heterocyclic Chemistry
• Year: 1999
• Tongue: English
• Weight: 201 KB
• Volume: 36
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570360539

✦ Synopsis

Abstract

A flavanone, in which a hydroxyl group at the 5‐position was protected with a methyl group, converted to the corresponding 5‐methoxy‐2‐phenyl‐4‐quinolone via flavylium salt under mild conditions. Flavanone‐O‐rhamnoglucoside, naringin, was also converted to 5‐methoxy‐2‐phenyl‐4‐quinolon‐7‐O‐rhamnoglucoside in the same way in an overall 25% yield.