16-epoxy-17-hydroxykaura-19-oic acid, ent-kaura-17,19-dioic acid, ent-kaur-16-en-19-oic acid, grandifloric acid, angeloyloxygrandifloric acid, as well as a new sesquiterpene lactone, ladibranolide, were isolated from Viguiera ladibractate. The stereochemistry of the sesquiterpene lactone was established by NOE experiments.
摘要 八种已知的二萜酸,ent-12-oxokaur-9(11),16-dien-19-oic acid, ent-12β-hydroxykaur-9(11),16-dien-19-oic acid, ent-isokaur- 15(16)-en-17,19-dioic acid, ent-15α,16-epoxy-17-hydroxykaura-19-oic acid, ent-kaura-17,19-dioic acid, ent-kaur-16-en-从 Viguiera ladibractate 中分离出 19-oic 酸、grandifloric 酸、Angeloyloxygrandifloric 酸以及新的
倍半萜内酯 ladibranolide。
倍半萜内酯的立体
化学是通过 NOE 实验建立的。