(4R)-hydroxy-(6R)-2,2,6-trimethylcyclohexanone + NAD(+) => (6R)-2,2,6-trimethyl-1,4-cyclohexanedione + NADH + H(+)
(4r)-hydroxy-(6r)-2,2,6-trimethylcyclohexanone + nad(+) => (6r)-2,2,6-trimethyl-1,4-cyclohexanedione + nadh + h(+)