Stereospecificity in allergic contact dermatitis to simple substituted methylene lactone derivatives

The enantiomers of beta,gamma-dimethyl- and beta-methyl-alpha-methylene-gamma-butyrolactones have been synthesized stereospecifically from glutamic acid and beta-hydroxy isobutyric acid, respectively. Guinea pigs have been sensitized (Freund complete adjuvant technique) and tested to them. Both enantiomers of beta-methyl lactone as well as (+)-beta,gamma-dimethyl lactone induced enantiospecific allergic contact dermatitis (ACD); in turn, (-)-beta,gamma-dimethyl lactone showed no specificity. An interpretation is proposed.