163163-23-3 293B Cpd 6-cyano-4-(N-ethylsulfonyl-N-methylamino)-3-hydroxy-2,2-dimethylchromane Chromanol 293B Ethanesulfonamide, N-((3R,4S)-6-cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl)-N-methyl-, rel-