preferred_name: (R)-S-adenosyl-L-methionine => (S)-S-adenosyl-L-methionine
preferred_name_lc: (r)-s-adenosyl-l-methionine => (s)-s-adenosyl-l-methionine
label: (R)-S-adenosyl-L-methionine => (S)-S-adenosyl-L-methionine
label_lc: (r)-s-adenosyl-l-methionine => (s)-s-adenosyl-l-methionine