a pyrimidine nucleobase + D-ribose 5-phosphate => a pyrimidine ribonucleoside 5'-phosphate + H2O
a pyrimidine nucleobase + d-ribose 5-phosphate => a pyrimidine ribonucleoside 5'-phosphate + h2o
a pyrimidine nucleobase + D-ribose 5-phosphate => a pyrimidine ribonucleoside 5'-phosphate + H2O
a pyrimidine nucleobase + d-ribose 5-phosphate => a pyrimidine ribonucleoside 5'-phosphate + h2o