Two new derivatives of patulin (1), the dimer (2) arising from cycloadditio
n at the 3,4-double bond, and 3, 4-dihydroxypatulin acetonide (4), from att
empted epoxidation with dimethyldioxirane, have been characterized. The str
ucture of (2) was established by a single-crystal low-temperature X-ray stu
dy, while that of (4) was deduced from spectroscopic studies.