Spiro[1,3-dithiolo[4,5-b]furan-2,3′(2′H)-furan], hexahydro-2′,3a-dimethyl-
Hexahydro-2′,3a-dimethylspiro[1,3-dithiolo[4,5-b]furan-2,3′(2′H)-furan]
2′,3-Dimethyl-3′,4-dioxa-2,8-dithiabicyclo[3.3.0]octanespirocyclopentane
2′,3a-Dimethyl-tetrahydrospiro[[1,3]dithiolo[4,5-b]furan-2,3′-oxolane]