1 LCE (1s,3s,4s,5s)-7,7-dichloro-3-methoxy-2-thiabicyclo[3.2.0]heptan-6-one-4-carboxylic acid 1.000 2 8TW (1~{S},4~{R},5~{S})-7,7-bis(chloranyl)-6,6-bis(oxidanyl)-2$L^{4}-thiabicyclo[3.2.0]hept-2-ene-4-carboxylic acid 0.812