Metabolism of 1-(4-hydroxy-3-methoxyphenyl)-2-propanone, a smoke flavour ketone, in rat.

1. Metabolites of 1-(4-hydroxy-3-methoxyphenyl)-2-propanone (HMP-one), a smoke flavour compound, were isolated from rat urine using hydrolysis, ether extraction, t.l.c. and g.l.c. 2. Three metabolites were identified by mass spectrometry and independent synthesis, namely: 1-(3, 4-dihydroxyphenyl)-2-propanone (Met I), 1-(3, 4-dihydroxyphenyl)-2-propanol (Met II), and 1-(4-hydroxy-3-methoxyphenyl)-2-propanol (Met III). 3. A g.l.c. method for the quantitative determination of the parent compound and metabolites in urine was devised. Unchanged HMP-one accounted for about 74% dose, with Met I 11%, Met II 5%, and Met III 9%. All compounds were excreted both as sulphate and glucuronide conjugates.