preferred_name: a (2S)-2-methylacyl-CoA => a (2R)-2-methylacyl-CoA
preferred_name_lc: a (2s)-2-methylacyl-coa => a (2r)-2-methylacyl-coa
label: a (2S)-2-methylacyl-CoA => a (2R)-2-methylacyl-CoA
label_lc: a (2s)-2-methylacyl-coa => a (2r)-2-methylacyl-coa