**4. Conclusions**

The first phytochemical investigation of the leaves and twigs of the Taiwanese endemic plant *Callicarpa hypoleucophylla* has resulted in the isolation of nine clerodane-type diterpenoids, compounds **1**–**9**, including two new compounds designated callihypolins A and B (compounds **1** and **2**). All isolates from *C. hypoleucophylla* possess a TC *ent*-clerodane skeleton, which is different from that of the phyllocladane and labdane diterpenoids that were identified as major components of the other well-studied species *Callicarpa macrophylla* Vahl, which is recorded in the Pharmacopoeia of the People's Republic of China. These results reflect the unique properties of *C. hypoleucophylla* from the perspective of chemotaxonomy. Moreover, the anti-inflammatory activity of the isolated compounds highlights the potential of clerodane-type diterpenoids for further pharmaceutic development.

**Supplementary Materials:** The NMR spectra of compounds **1** and **2** are available online.

**Author Contributions:** Y.-B.C., C.-Y.C. and C.-H.W. conceived and designed the experiments; Y.-C.L. and J.-J.L. carried out the plant extraction and isolation of the compounds; T.-L.H., S.-Y.F., and M.K. conducted the biological studies; M.-H.Y. collected and identified the material; C.-Y.C., Y.-S.L., and T.-Y.W. assisted with the interpretation of various data; Y.-C.L., S.-R.C., Y.-B.C. contributed to the writing of the manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was funded by grants from the Ministry of Science and Technology of Taiwan (MOST-107-2628-B-037-001 and MOST-108-2320-B-037-013-MY3 awarded to Prof. Yuan-Bin Cheng; MOST 106-2320-B-255-003-MY3 and MOST 108-2320-B-255-003-MY3 awarded to Prof. Tsong-Long Hwang). This work was also supported by grants from Zuoying Branch of Kaohsiung Armed Forces General Hospital (KAFGH-ZY-A-109030).

**Conflicts of Interest:** The authors declare no conflict of interest.

### **References**


**Sample Availability:** Samples of the compounds are available from the authors.

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