preferred_name: a cis-alkene + CO2 => a cis-3-alkyl-4-alkyloxetan-2-one
preferred_name_lc: a cis-alkene + co2 => a cis-3-alkyl-4-alkyloxetan-2-one
label: a cis-alkene + CO2 => a cis-3-alkyl-4-alkyloxetan-2-one
label_lc: a cis-alkene + co2 => a cis-3-alkyl-4-alkyloxetan-2-one