(2R)-2,3-dihydroxy-3-methylbutanoate + NADP(+) => 3-hydroxy-3-methyl-2-oxobutanoate + NADPH + H(+)
(2r)-2,3-dihydroxy-3-methylbutanoate + nadp(+) => 3-hydroxy-3-methyl-2-oxobutanoate + nadph + h(+)
(2R)-2,3-dihydroxy-3-methylbutanoate + NADP(+) => 3-hydroxy-3-methyl-2-oxobutanoate + NADPH + H(+)
(2r)-2,3-dihydroxy-3-methylbutanoate + nadp(+) => 3-hydroxy-3-methyl-2-oxobutanoate + nadph + h(+)