preferred_name: a ribonucleoside + a 2'-deoxyribonucleoside 5'-phosphate => a 2'-deoxyribonucleoside + a ribonucleoside 5'-phosphate
preferred_name_lc: a ribonucleoside + a 2'-deoxyribonucleoside 5'-phosphate => a 2'-deoxyribonucleoside + a ribonucleoside 5'-phosphate
label: a ribonucleoside + a 2'-deoxyribonucleoside 5'-phosphate => a 2'-deoxyribonucleoside + a ribonucleoside 5'-phosphate
label_lc: a ribonucleoside + a 2'-deoxyribonucleoside 5'-phosphate => a 2'-deoxyribonucleoside + a ribonucleoside 5'-phosphate