Send to

Choose Destination
Org Lett. 2016 Jan 4;18(1):120-3. doi: 10.1021/acs.orglett.5b03360. Epub 2015 Dec 18.

Callistrilones A and B, Triketone-Phloroglucinol-Monoterpene Hybrids with a New Skeleton from Callistemon rigidus.

Author information

Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy and ‡JNU-HKUST Joint Laboratory for Neuroscience & Innovative Drug Research, Jinan University , Guangzhou 510632, People's Republic of China.


The first triketone-phloroglucinol-monoterpene hybrids, callistrilones A and B (1 and 2), along with a postulated biosynthetic intermediate (3) were isolated from the leaves of Callistemon rigidus. Compounds 1 and 2 featured a new carbon skeleton with an unprecedented [1]benzofuro[2,3-a]xanthene or [1]benzofuro[3,2-b]xanthene pentacyclic ring system composed of three kinds of building blocks. Their structures and absolute configurations were elucidated by spectroscopic analysis, X-ray diffraction, and electronic circular dichroism (ECD) calculations. A plausible biogenetic pathway for the new compounds is also proposed. Compound 1 exhibited moderate antibacterial activity against Gram-positive bacteria including multiresistant strains.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center