Synthesis and Structure Determination of Covalent Conjugates Formed from the Sulfury−Roasty-Smelling 2-Furfurylthiol and Di- or Trihydroxybenzenes and Their Identification in Coffee Brew
products is responsible for the rapid aroma staling of coffee beverages. To get a clear understanding of the molecular mechanisms underlying this aroma staling, the existence of putative phenol/thiol conjugates needs to be verified in coffee. The aim of the present study was therefore to synthesize such conjugates for use as reference substances for LC-MS screening of coffee. To achieve this, catechol, 3-methyl-