label: [(3R)-hydroxybutanoate](n-2) + (3R)-hydroxybutanoate dimer + H(+) => [(3R)-hydroxybutanoate](n) + H2O
label_lc: [(3r)-hydroxybutanoate](n-2) + (3r)-hydroxybutanoate dimer + h(+) => [(3r)-hydroxybutanoate](n) + h2o