A new cassane diterpenoid lactone from the seed of Caesalpinia minax

A new cassane diterpenoid lactone was isolated from the seed of Caesalpinia minax. On the basis of spectral evidences, its structure was established as 12α-methoxyl, 5α, 14β-dihydroxy-1α, 6α, 7β-triacetoxycass-13（15）-en-16, 12-olide.

Distinctive Cassane Diterpenoids Corroborated Biogenetic Evolutionary Process from Caesalpinia mimosoides with Anti-renal Fibrosis Activity

Eighteen diterpenoids were isolated from the seeds of Caesalpinia mimosoides,including four extremely infrequent cassane diterpenes,together with nine new and five known structures.Compounds 7 and 8 represent the first examples of cassane diterpenoids fused with a ketone carbonyl and a ternary oxygen ring at C-4,respectively.Compounds 9 and 10 possess a rare five-member ring in cassane diterpenes.Intriguingly,these isolated components are a clue to the fact that there are lower and higher levels in the plant secondary metabolites,demonstrating the evolution of secondary metabolism of C.mimosoides.All the isolated compounds were tested for their anti-renal fibrosis activity against TGF-β1 induced NRK-52E cell model.The mRNA levels of fibrosis markerα-SMA,E-cadherin,Collagen I were tested by qRT-PCR.The data showed compounds 6 and 9 exhibited the best anti-renal fibrosis activity and provided preliminary structure−activity relationships.

New Cassane Diterpenoids from the Seed Kernels of Caesalpinia cucullata, Exhibit Anti-inflammatory Effect in vitro by Inhibiting iNOS Enzymatic Activity

Inflammation is a complex biological response to stimulation.Natural cassane diterpenoids from Caesalpinia genus exhibit significant anti-inflammation activity.Eight new cassane diterpenoids(1-8)along with seven known ones(9-15)were obtained from the seed kernels of Caesalpinia cucullata Roxb.This is the first report on chemical investigation of the seed kernels of C.cucullata,and the cassane diterpenes were found in this plant for the first time.Their structures were elucidated based on the extensive spectroscopic analyses,and the absolute configurations were identified by ECD calculation and X-ray crystallography.All compounds were evaluated for their anti-inflammation activity by inhibiting NO production in LPS-induced RAW 264.7 cells.Compounds 1-2 and 9-11 exhibited effective inhibitory activity with inhibition rate more than 50%.The iNOS enzyme activity and molecular docking experiments were performed to explore the preliminary mechanism.Eventually,a potential anti-inflammatory mechanism revealed that the bioactive cassane inhibited overproduction of NO by targeting key residues in the iNOS active cavity to reduce iNOS enzymatic activation.

Cytotoxic cassane diterpenoids from the seeds of Caesalpinia sappan

Phytochemical investigation on the seeds of Caesalpinia sappan led to the isolation of five new cassanetype diterpenoids, named 11-oxo-phanginin A（1）, caesalsappanins O–Q（2–4） and phanginin U（5）,together with five known compounds. The structures of the new compounds were elucidated by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. All the new compounds showed moderate cytotoxic effects on human breast cancer MCF-7 and human colon cancer HCT116 cell lines.

Biscaesalmins A and B from Caesalpinia minax,highly oxidized dimeric cassane diterpenoids as interleukin-1β inhibitors

To search naturally occurring interleukin-1β(IL-1β) inhibitors,biscaesalmins A(1) and B(2),two highly oxidized dimeric cassane diterpenoids with a newly formed alicyclic skeleton,have been isolated from the traditional Chinese medicine Kushilian(Caesalpinia minax).Their full structures were determined by comprehensive spectroscopic analysis and quantum chemical TD-DFT(time-dependent density functional theory) calculation.Biosynthetically,1 and 2 were formed via an intermolecular [4+2]Diels-Alder cycloaddition of two monomers,affording an additional six-membered carbon ring linkage.Compounds 1 and 2 inhibited nitric oxide production on lipopolysaccharide-stimulated THP-1 macrophages,with IC_(50) values being at 1.20±0.23 and 2.30±0.15 μmol/L,respectively.Furthermore,compound 1 inhibited NLRP3(NOD-,LRR-and pyrin domain-containing protein 3) inflammasomemediated IL-1β production and blocked the migration of macrophages towards adipocyte conditioned medium.Biscaesalmins A and B might be candidates for treating inflammation-related metabolic diseases.