Randainins A–D, Based on Unique Diterpenoid Architectures, from Callicarpa randaiensis

Abstract

Four new compounds, randainins A-D (1-4), were isolated from the leaves and twigs of Callicarpa randaiensis, which is an endemic species in Taiwan. Compounds 1 and 2 are diterpenoids with an unusual trans-7/5 ring system, whereas compounds 3 and 4 are diterpenoids possessing a trans-5/7 ring scaffold. The structures of the new compounds were established based on NMR and MS data analyses. Anti-inflammatory activities and cytotoxicity were tested and evaluated for these compounds. Compound 4 exhibited moderate inhibition of superoxide-anion generation with an IC50 value of 21.5 ± 2.5 μM.

Clerodane Diterpenoids from Callicarpa hypoleucophylla and Their Anti-Inflammatory Activity

“…Because the phytochemical profile of the Taiwanese endemic plant Callicarpa hypoleucophylla has never been analyzed, we carried out an investigation of the constituents and bioactivity of C. hypoleucophylla. A meticulous separation of an ethanolic extract of C. hypoleucophylla led to the isolation of two new clerodane-type diterpenoids that we named callihypolins A and B (1 and 2), together with seven known analogues (3)(4)(5)(6)(7)(8)(9). The anti-inflammatory evaluation of these isolates is also presented in this paper.…”

“…The phytochemical investigation of this genus has resulted in the identification of diterpenoids, phenylethanoids, phenypropanoids, and flavonoids. These components display various biological effects, such as anti-inflammatory [4][5][6], anti-platelet aggregation [7], hemostatic [8], antioxidative [9][10], cytotoxic [6,[11][12], and neuroprotective [13], antitubercular [14], hepatoprotective [15][16], antimicrobial [17], anti-arthritic [18], as well as analgesic properties [19]. From the above-mentioned phytochemical and biological studies, we know this genus may offer a rich supply of bioactive phytochemicals.…”

Biological Activity of Selected Natural and Synthetic Terpenoid Lactones

“…It can downregulate the expressions of the COX-1, COX-2, and iNOS genes [ 57 ]. Randainin D, a new diterpenoid found in Callicarpa randaiensis , exhibited mild inhibition of elastase release and moderate superoxide anion generation inhibitory activity of 35.9% at a concentration of 28.6 μM and an IC 50 value of 21.5 μM [ 58 ]. New inositol lactones with anti-inflammatory potential isolated from Inula montana showed an impact on the release of NO on RAW 264.7 macrophages with IC 50 values below 30 μM [ 59 ].…”

Natural Products Research in China From 2015 to 2016

“…Four new iridals with an α-terpineol moiety resulting from cyclization of the homofarnesylside chain, polycycloiridals A–D ( 650 - 653 ), were from the rhizomes of Iris tectorum (Zhang et al, 2015a ). Diterpenoid randainins A–D ( 654 - 657 ) with a trans -fused 7/5 or 5/7 ring system were isolated from leaves and twigs of Callicarpa randaiensis (Nantou, Taiwan, China) (Cheng et al, 2015 ). Research into Abies chensiensis led to the discovery of triterpenoid spirochensilides A ( 658 ) (Figure 11 ) and B ( 659 ) possessing a 8,10-cyclo-9,10-seco skeleton (Zhao et al, 2015b ).…”