1,4-dihydroxy-6-naphthoate + all-trans-octaprenyl diphosphate + H(+) = 2-demethylmenaquinol-8 + CO2 + diphosphate
1,4-dihydroxy-6-naphthoate + all-trans-octaprenyl diphosphate + h(+) = 2-demethylmenaquinol-8 + co2 + diphosphate