8-methyl-2,3,5,6,7,8-hexahydronaphtho[2,3-b]furan

2,3,7,8-tetrahydronaphtho<2,3-b>furan-5(6H)-one

2,3-dihydronaphtho[2,3-b]furan

2,3,6,7-tetrahydro-5H-naphtho[2,3-b]furan-8-one oxime