1 2 insecticidal component of pyrethrum flower heads, b it would be unique among natural product structures in having an isopropylidenecyclopropane nucleus and in being a cyclopropanol ester. 6 The isolation of this attractant was an extremely arduous task, requiring nine months' continuous “milking” of 10,000 virgin females to obtain only 12.2 mg. of inaterial. 2 It is not surprising, therefore, that only a limited amount of classical structural ...
