Reactivity of 4a,5-epoxy-5-deazaflavins

Reactions of 4a,5-epoxy-5-deazaflavins with aqueous potassium carbonate, Vilsmeier reagent (dimethylformamide-phosphorus oxychloride), acetic anhydride-acetic acid, pyridine and triethanolamine gave the corresponding oxazolonoquinolines, 5-chloro-5-deazaflavins, 4a,5-diacetoxy-5-deazaflavins, 1,5-dihydro-5-deazaflavin-5-ones, and deoxygenated 5-deazaflavins, respectively.