Four new terpenes from the pericarp of Platycladus orientalis

Diverse diterpenoids from Callicarpa rubella Lindl. As natural inhibitors of macrophage foam cell formation

Ten undescribed diterpenoids namely rubellawus E-N of structural types pimarane (1, 3-4), nor-abietane (2), nor-pimarane (5-6), isopimarane (7-9), and nor-isopimarane (10), along with eleven known compounds, were isolated and identified from the aerial parts of Callicarpa rubella Lindl. The structures of the isolated compounds were confirmed by comprehensive spectroscopic analyses and quantum chemical computations. Pharmacologically, almost all the compounds exhibited a potential inhibitory effect on oxidized low-density lipoprotein-induced macrophage foam cell formation, which suggests that these compounds may be promising candidates in the treatment of atherosclerosis.

Diterpenoids from Callicarpa rubella and their in vitro anti-NLRP3 inflammasome activity

Nine new diterpenoids, Rubellacrns A - I (1-9), including five isopimaranes (1-4, 9), four pimaranes (5-8), together with five known isopimarane analogues (10-14), were isolated from Callicarpa rubella. The structures of these compounds were unambiguously established by HR-ESIMS and NMR spectroscopic data, the absolute configurations of compounds 5 and 9 were determined by ECD. All the isolated compounds were tested for their anti-inflammatory effects and compounds 2 and 11-14 showed NLRP3-inflammasome inhibitory activity with IC₅₀ values ranging from 7.02 to 14.38 μM.

Rubellawus A-D, Four New Diterpenoids Isolated from Callicarpa rubella and Their Anti-NLRP3 Inflammasome Effects

Four new diterpenoids, rubellawus A-D (1-4), along with three known compounds, were isolated and identified from the flowers of Callicarpa rubella. Their structures were elucidated by various spectroscopic analysis. All the compounds were screened for their anti-inflammatory activity and 14α-hydroxyisopimaric acid and isopimaric acid showed significant NLRP3 inflammasome inhibitory activity with IC₅₀ values of 7.02 and 3.99 μM.

Caryopincaolide M, a rearranged abietane diterpenoid with new skeleton and a new iridoid from Caryopteris incana

Caryopincaolide M (1), a new rearranged abietane diterpenoid with an unusual pent-4-enoic acid group on a 6/6/5 tricyclic ring system, and 7-epi-8-dehydroxypatriscabrol (3), a new iridoid, together with 17 known compounds, have been isolated from the whole plant of Caryopteris incana (Thunb.) Miq. Their structures were elucidated on the basis of 1-D and 2-D NMR, IR, and mass spectroscopic data. Compounds 1-5 were evaluated for their inhibitory activities against enzyme α-glucosidase, and the results showed that only 1 has moderate inhibitory activity against enzyme α-glucosidase with IC₅₀ at 528.3 ± 12.37 mg/L.

Platycladus orientalis leaves: a systemic review on botany, phytochemistry and pharmacology

Platycladus orientalis leaves (Cebaiye) have been used for thousands of years as traditional Chinese medicine (TCM). According to the theory of TCM, they are categorized as a blood-cooling and hematostatic herb. In clinical practice, they were usually prescribed with heat-clearing herbs to reinforce the efficacy of hemostasis. The review provides the up-to-date information from 1980 to present that is available on the botany, processing research, phytochemistry, pharmacology and toxicology of the leaves. The information is collected from scientific journals, books, theses and reports via library and electronic search (Google Scholar, Pubmed and CNKI). Through literature reports, we can find that the leaves show a wide spectrum of pharmacological activities, such as anti-inflammatory, antioxidant, antimicrobial, disinsection, anticancer, diuretic, hair growth-promoting, neuroprotective and antifibrotic activities. Diterpene and flavonoids would be active constituents in P. orientalis leaves. Many studies have provided evidence for various traditional uses. However, there is a great need for additional studies to elucidate the mechanism of blood-cooling and hematostatic activity of the leaves. Therefore, the present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies of this herb.

A New Labdane Diterpene from Rauvolfia Tetraphylla Linn. (Apocynaceae)

The air-dried stems and branches of Rauvolfia tetraphylla afforded a new labdane diterpene characterised as 3β-hydroxy-labda-8(17),13(14)-dien-12(15)-olide on the basis of spectroscopic studies including UV, IR, MS and NMR (1H, 13C and HMQC); this is the first report of a new terpenoid constituent from R. tetraphylla, an important medicinal plant widely known for the source of a variety of alkaloids.

Diterpenoids from the pericarp of Platycladus orientalis

Eight labdane-type diterpenes, 7beta,13S-dihydroxylabda-8(17),14-dien-19-oic acid (1), 12R,15-dihydroxylabda-8(17),13E-dien-19-oic acid (3c), 12R,15-dihydroxylabda-8(17),13Z-dien-19-oic acid (3d), 12R,13R,14S-trihydroxylabda-12,15-epoxy-8(17)-en-19-oic acid (4a), 12S,13S,14R-trihydroxylabda-12,15-epoxy-8(17)-en-19-oic acid (4b), 15-hydroxy-12-oxolabda-8(17),13E-dien-19-oic acid (5), 14R,15-dihydroxylabda-8(17),12Z-dien-19-oic acid (7a) and 14S,15-dihydroxylabda-8(17),12Z-dien-19-oic acid (7b), along with 20 known diterpenoids, were isolated from the pericarp of Platycladus orientalis. Their structures were unambiguously elucidated by NMR spectroscopic and single crystal X-ray diffraction analyses, as well as via chemical correlation conversion. NMR spectroscopic data of known isomers 8c and 8d were reported as a supplement to existing data.

Labdane diterpenes from the seeds of Platycladus orientalis

Two new labdane diterpenes, 14(R),15-dihydroxy-8(17),12(E)-labdadien-19-oic acid (1) and 16-methyl-12,15-epoxy-8(17),13-labdadien-19-oic acid (2), together with four known compounds, were isolated from the seeds of Platycladus orientalis. Their structures were established by spectroscopic methods. The stereochemistry of compound 1 was defined by X-ray crystallographic analysis.