New Volatile Sulfur-Containing Constituents in a Simultaneous Distillation-Extraction Extract of Red Bell Peppers (Capsicum annuum)

摘要

An extract of red bell peppers (Capsicum annuum) was prepared by simultaneous distillation-extraction (SDE,Likens-Nickerson).In addition to the already known (3E)-3-hepten-2-one (1),the unsaturated C9-ketones 1-nonen-4-one (2),(2E)-2-nonen-4-one (3),and (2E,5E)-2,5-nonadien-4-one (4),2-meth-oxy-3-isobutylpyrazine (5),and heptane-2-thiol (6),we identified 19 new thiols (the aliphatic saturated and unsaturated thiols 14-16,and 22-27,the mercapto-ketones 12 and 13,the mercapto-alcohols 17,18,and 30,the dithiols 19 and 28,the methylthio-thiols 20 and 21,and the thiophene-thiol 31) and the two new dithiolanes 10 and 29.All of them are structurally related to the unsaturated C7-and C9-ketones 1 -4.The free thiols were enriched using Affi-Gel 501 (p-aminophenyl-mercuric acetate grafted on an agarose gel).The new compounds were confirmed by syntheses and were organoleptically evaluated.