preferred_name: an L-alpha-amino acid + a fatty acid => an N-fatty-acyl-L-alpha-amino acid + H2O
preferred_name_lc: an l-alpha-amino acid + a fatty acid => an n-fatty-acyl-l-alpha-amino acid + h2o
label: an L-alpha-amino acid + a fatty acid => an N-fatty-acyl-L-alpha-amino acid + H2O
label_lc: an l-alpha-amino acid + a fatty acid => an n-fatty-acyl-l-alpha-amino acid + h2o