Enzymatic oxidation of veratryl alcohol yielded a new ring cleavage product (δ-lactone) in addition to the two known γ-lactone products. The experiment with 18O-enriched water and dioxygen clearly showed that one oxygen atom each from water and dioxygen is specifically incorporated into the cleavage product at the original C3 or C4 position of 3,4-dimethoxybenzyl alcohol. A new type of reaction mechanism proposed for the ring cleavage of this compound is rationally explained in good accord with the one-electron transfer mechanism.
