androsta-1,4-diene-3,17-dione + AH2 => androst-4-ene-3,17-dione + A
androsta-1,4-diene-3,17-dione + ah2 => androst-4-ene-3,17-dione + a
androsta-1,4-diene-3,17-dione + AH2 => androst-4-ene-3,17-dione + A
androsta-1,4-diene-3,17-dione + ah2 => androst-4-ene-3,17-dione + a