preferred_name: a purine D-ribonucleoside + H2O => a purine nucleobase + D-ribose
preferred_name_lc: a purine d-ribonucleoside + h2o => a purine nucleobase + d-ribose
label: a purine D-ribonucleoside + H2O => a purine nucleobase + D-ribose
label_lc: a purine d-ribonucleoside + h2o => a purine nucleobase + d-ribose