title: Reinvestigation of the reaction between 2-furancarboxaldehyde and 4-hydroxy-5-methyl-3(2H)-furanone.
abstract: The reaction between 2-furancarboxaldehyde and 4-hydroxy-5-methyl-3(2H)-furanone was reinvestigated as a part of a systematic study on low molecular weight colored compounds from the Maillard reaction. In acetic acid/piperidine, besides 2-(2-furanylmethylene)-4-hydroxy-5-methyl-3(2H)-furanone (1) and 5-[2-(2-furanyl)ethenyl]-2-(2-furanylmethylene)-4-hydroxy-5-methyl -3( 2H)-furanone (2), four novel compounds, 15a, 15b, 16a, and 16b, were isolated and characterized. These compounds are produced from two molecules of furanone 1 and one molecule of 2-furancarboxaldehyde, and a mechanism is proposed for their formation. Compounds 1, 15a, 15b, 16a, and 16b are formed also by reacting 2-furancarboxaldehyde and 4-hydroxy-5-methyl-3(2H)-furanone in water at pH 3 and 2, whereas 2 was never detected. The formation of these compounds was studied also in xylose/lysine and xylose/glycine model systems.
authors.affiliation: Dipartimento di Scienze Molecolari Agroalimentari, Sezione di Chimica, Università di Milano, via Celoria 2, I-20133 Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Ravagli
authors.forename: G
authors.initials: G
authors.lastname: Boschin
authors.forename: L
authors.initials: L
authors.lastname: Scaglioni
authors.forename: A
authors.initials: A
authors.lastname: Arnoldi
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005662:Furaldehyde / Q000737:chemistry*; D005663:Furans / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015416:Maillard Reaction; D013058:Mass Spectrometry
chemical_list: D005663:Furans; D005662:Furaldehyde; C113254:4-hydroxy-5-methyl-3(2H)-furanone