Stereochemistry of -Acyl-5-dibenzo[,]azepin-7(6)-ones.

The stereochemical properties of -acyl-5-dibenzo[,]azepin-7(6)-ones (-), which inhibit potassium channels in T cells, were examined by freezing their conformational change due to 4-methyl substitution. -Acyl-5-dibenzo[,]azepin-7(6)-ones exist as pairs of enantiomers [(a, a), (a, a)], and each atropisomer is separable at room temperature. An alternate procedure for preparing 5-dibenzo[,]azepin-7(6)-ones involves the intramolecular Friedel-Crafts cyclization of -benzyloxycarbonylated biaryl amino acids. Consequently, the -benzyloxy group was removed during the cyclization reaction to produce 5-dibenzo[,]azepin-7(6)-ones suitable for the subsequent -acylation reaction.