应该是一种生物大分子!
http://www.journalarchive.jst.go ... en&from=jnlabstract
PAPULACANDINS - SYNTHESIS AND BIOLOGICAL ACTIVITY
OF PAPULACANDIN B DERIVATIVES
Peter Traxler, Werner Tosgh and Oto Zak
Research Department, Pharmaceuticals Division, CIBA-GEIGYLimited,