Synthesis of .alpha.-methylene-.gamma.-butyrolactones: a structure-activity relationship study of their allergenic power

Abstract
.alpha.-Methylene-.gamma.-butyrolactones (35) were prepared and their allergenic properties tested on the skin of guinea pigs experimentally sensitized to alantolactone, isoalantolactone and .alpha.-methylene-.gamma.-butyrolactone. The first 2 groups of animals cross-react to lactones containing 9-18 C atoms but not to smaller .alpha.-methylene-.gamma.-butyrolactones. Animals sensitized to .alpha.-methylene-.gamma.-butyrolactone react only with .alpha.-methylene-.gamma.-butyrolactones containing 6 and 7 C atoms. These results are discussed in relation to the allergic contact dermatitis mechanism.