4-Quinolinemethanesulfonic acid, 6,6'-methylenebis(1,2-dihydro-2,2-dimethyl- 6,6'-methylenebis(2,2-dimethyl-4-methanesulfonic acid-1,2-dihydroquinoline) 77228-64-9 90829-56-4 Mtdq-DA Mtdq-DS