D-glucose 6-phosphate + D-glucose => alpha-maltose 6'-phosphate + H2O
d-glucose 6-phosphate + d-glucose => alpha-maltose 6'-phosphate + h2o
D-glucose 6-phosphate + D-glucose => alpha-maltose 6'-phosphate + H2O
d-glucose 6-phosphate + d-glucose => alpha-maltose 6'-phosphate + h2o