2H-oxocin, 6,7-didehydro-3,4,5,8-tetrahydro- 3,4-didehydro-5,6,7,8-tetrahydro-2H-oxocine InChI=1/C7H10O/c1-2-4-6-8-7-5-3-1/h1-2,4,6-7H