(S)-5-carboxymethyl-tetronate + o-quinone methide => penilactone D + H(+)
(s)-5-carboxymethyl-tetronate + o-quinone methide => penilactone d + h(+)
(S)-5-carboxymethyl-tetronate + o-quinone methide => penilactone D + H(+)
(s)-5-carboxymethyl-tetronate + o-quinone methide => penilactone d + h(+)