Chemical studies on the Philippine crude drug calumbibit (seeds of Caesalpinia bonduc): the isolation of new cassane diterpenes fused with alpha,beta-butenolide

New cassane diterpenes named neocaesalpins C and D were isolated from the Philippine crude drug calumbibit botanically originating from the seeds of Caesalpinia bonduc (Fabaceae), and their structures were elucidated on the basis of the spectroscopic evidence. These compounds are characterized by the presence of the alpha,beta-butenolide moiety. Although a number of cassane furanoditerpenes have been known to occur in the same plant species, such constituents could not be isolated from the crude drug of Philippine origin in this study. It is presumed that the chemical difference resulted from chemical differentiation of the species.     

Further Diterpenes from the Seeds of Caesalpinia minax Hance

Three new cassane‐type diterpenes, neocaesalpin AF ( 1 ), neocaesalpin AG ( 2 ), and neocaesalpin AH ( 3 ), were isolated from the seeds of Caesalpinia minax Hance . Their structures were elucidated on the basis of extensive spectroscopic analyses. The partially hydrogenated lactone unit in a tetracyclic cassane diterpene in 2 is rarely encountered in the cassane diterpenes isolated from the genus Caesalpinia. All compounds were evaluated for their in vitro cytotoxic activities against HCT‐8 and MCF‐7 human cancer cell lines.     

Cassane‐Type Diterpenes from the Seeds of Caesalpinia crista

A new dimer 1 and two new cassane‐type diterpenes 2 and 3 , designated taepeenin J–L, were isolated from the seeds of Caesalpinia crista L. Compound 1 possesses a dimeric vouacapane skeleton. Their structures were elucidated on the basis of spectroscopic analysis.     

Antioxidative Cassane Diterpenoids from the Seeds of Caesalpinia minax

Five new cassane diterpenoids, caesalmins I–M ( 1 – 5 ), and 23 known analogs were isolated from the seeds of Caesalpinia minax. Their structures were elucidated by spectroscopic methods and comparison with reported data. The antioxidant properties of 1 – 28 were determined by the method of oxygen radical absorbance capacity of fluorescein (ORAC‐FL), and 14 compounds exhibited good antioxidant activities with ORAC‐FL values of 2.24–4.89 Trolox equivalents. The structure? activity relationship of the active compounds was also discussed.     

Caesaldecan, a cassane diterpenoid from the leaves of Caesalpinia decapetala

A new cassane diterpenoid, caesaldecan, was isolated from Caesalpinia decapetala with eight known compounds, spathulenol, 4,5-epoxy-8(14)-caryophyllene, squalene, lupeol, trans-resveratrol, quercetin, astragalin, and stigmasterol. The (1)H- and (13)C-NMR spectra of the new compound were completely assigned by using a combination of 2D NMR techniques, namely, (1)H-(1)H COSY, HMQC, HMBC, and ROESY.     

Three New Cassane‐Type Diterpenes from Caesalpinia minax

Three new cassane‐type diterpenes, 14‐dehydroxy‐12,16‐dihydrocaesaldekarin L ( 1 ), 1‐deacetyl‐12‐ethoxyneocaesalpin N ( 2 ), and 1‐deacetylneocaesalpin N ( 3 ), together with two known cassane‐type diterpenes, neocaesalpin A and neocaesalpin L, were isolated from the EtOH extract of the twigs and leaves of Caesalpinia minax. Their structures were elucidated by spectroscopic methods, as well as by comparison of their spectral data with those of related compounds.     

Structure Revision of Caesalpinistas A and B and Isolation of a New Furanoditerpenoid from the Cotyledons of Caesalpinia decapetala var. japonica

A known cassane‐type furanoditerpenoid, caesalpinista B ( 1 ), and a new diterpenoid, deoxycaesaljaponin A ( 2 ), were isolated from the cotyledons of Caesalpinia decapetala var. japonica. The previously reported configurational assignments of 1 and the related diterpenoid caesalpinista A ( 3 ) were revised on the basis of X‐ray crystallography and chemical conversion. The structure of 2 was elucidated by spectroscopic data and chemical conversion into 3 .     

Three new cassane diterpenes from the seeds of Caesalpinia minax Hance

Four fractions were prepared from the crude extract of Caesalpinia minax Hance and the inhibitory activity of nitric oxide (NO) production release of RAW 264.7 cells stimulated by lipopolysaccharide (LPS) was evaluated. The ethyl acetate (EtOAc) fraction showed obvious inhibitory effect. Bioassay-guided fractionation led to the isolation of three new cassane diterpenes, caesalmin X (1), caesalmin Y (2) and caesalmin Z (3), together with 19 known cassane diterpenoids (4–22). Their structures were mainly characterised on the basis of extensive spectroscopic analyses and comparison with reported data. Moreover, three compounds (20–22) which possessed furanditerpenoid 7,17-lactone structures, displayed moderate activities, with IC₅₀ value of 29.85, 27.38 and 25.40 μM, respectively.     

Simultaneous identification and analysis of cassane diterpenoids in Caesalpinia minax Hance by high‐performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry

Cassane diterpenoids were successfully and simultaneously identified in Caesalpinia minax Hance by high‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. A total of 59 peaks were detected, and among them 51 compounds, including 41 furanocassane diterpenoids, 10 furanolactone cassane diterpenoids were simultaneously identified and characterized on the basis of the protonated molecule, retention behavior, and fragments in MS². Ten compounds, including seven novel compounds, were identified or tentatively identified for the first time in C. minax. In a positive ion mode, the fragmentation pathways of cassane diterpenoids were also analyzed for the first time. The relative amounts of the five main diterpenoids (caesalpinin L, caesalpinin F₂, bondcellpin C, caesalpinin E, and ξ‐caesalmin) were simultaneously quantified by high‐performance liquid chromatography. Results showed that the newly discovered and known components of C. minax can be used to determine the material basis of bioactivity; this method can also be applied to analyze cassane diterpenoids in herbal medicines from the genus Caesalpinia belonging to the family Fabaceae.     

Caesaljaponins A and B: New Cassane‐Type Furanoditerpenoids from the Seeds of Caesalpinia decapetala var. japonica

Two new cassane‐type furanoditerpenoids, designated caesaljaponin A and caesaljaponin B ( 1 and 2 , resp.), were isolated from seeds of Caesalpinia decapetala var. japonica. The structures were elucidated by spectroscopic data, and the absolute configuration of 1 was determined by X‐ray crystallographic analysis using the anomalous scattering of CuK_α radiation.     

Cassane‐Type Diterpenoids from the Seeds of Caesalpinia magnifoliolata

Two novel cassane‐type diterpenes, named magnicaesalpin ( 1 ) and neocaesalpin O ( 2 ), together with three known compounds, caesalmin D ( 3 ), caesalmin E ( 4 ), and neocaesalpin L ( 5 ), were isolated from the MeOH extract of seeds of Caesalpinia magnifoliolata Metc . Their structures were determined by spectroscopic methods, (1D‐ and 2D‐NMR, HR‐EI‐MS) and X‐ray analysis, as well as by comparison of their spectral data with those of related compounds.     

Two new cassane diterpene lactams from the fruits of Caesalpinia mimosoides Lam

Two new cassane ditepenoid lactams, caesmimotam A (1) and B (2), along with eight known compounds (3–10) were isolated from the fruits of Caesalpinia mimosoides Lam. Their structures were identified by 1D and 2D NMR spectral data. Compounds 1 and 2 were evaluated for their cytotoxicity on HL-60, SMMC-7721, A-549, MCF-7 and SW-480 human cancer cell lines, but they were inactive.     

The genus Caesalpinia L. (Caesalpiniaceae): phytochemical and pharmacological characteristics

The genus Caesalpinia (Caesalpiniaceae) has more than 500 species, many of which have not yet been investigated for potential pharmacological activity. Several classes of chemical compounds, such as flavonoids, diterpenes, and steroids, have been isolated from various species of the genus Caesalpinia. It has been reported in the literature that these species exhibit a wide range of pharmacological properties, including antiulcer, anticancer, antidiabetic, anti-inflammatory, antimicrobial, and antirheumatic activities that have proven to be efficacious in ethnomedicinal practices. In this review we present chemical and pharmacological data from recent phytochemical studies on various plants of the genus Caesalpinia.     

New cassane-type diterpenes of Caesalpinia crista from Myanmar

Seven new cassane-type diterpenes, caesalpinin MF-ML (1-7), and a new norcassane-type diterpene, norcaesalpinin MD (8), have been isolated from the CH2Cl2 extract of seed kernels of Caesalpinia crista from Myanmar, together with sixteen known cassane-type diterpenes, 7-acetoxybonducellpin C, caesaldekarin e, caesalmin C, caesalmin G, 2-acetoxycaesaldekarin e, zeta-caesalpin, caesalpinin D, caesalpinin E, caesalpinin F, caesalpinin H, caesalpinin I, caesalpinin J, caesalpinin K, caesalpinin M, caesalpinin N, and caesalpinin O. The structures of the isolated compounds were elucidated by the use of spectroscopic techniques.     

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.     

Glutathione S-transferase inhibiting chemical constituents of Caesalpinia bonduc

Glutathione S-transferase inhibition assay-guided fractionations on the ethanolic extract of the bark of Caesalpinia bonduc resulted in the isolation of a new sterol, 17-hydroxy-campesta-4,6-dien-3-one (1) along with four known compounds, 13,14-seco-stigmasta-5,14-dien-3alpha-ol (2), 13,14-seco-stigmasta-9(11),14-dien-3alpha-ol (3), caesaldekarin J (4) and pipataline (5) as active constituents. Structures of compounds 1-5 were established on the basis of extensive NMR spectroscopic studies. The compounds (1-5) were isolated on the basis of their inhibitory activity against glutathione S-transferase, an enzyme that has been implicated in resistances during treatment of cancer and parasitic infections. Efforts to study structure-activity relationships of compounds 2 and 3 were also made by modifying their structures. The IC50 values of these compounds and their derivatives ranged from 57-380 microM and were compared to the inhibitory effects due to sodium taurocholate, an isoprene-derived GST inhibitor (IC50=398 microM). A plausible biosynthesis of 13,14-seco-steroids has also been proposed.     

A new homoflavonoid from the seed of Caesalpinia minax Hance

<正>A new homoflavonoid was isolated from the seed of Caesalpinia minax Hance.On the basis of spectral evidences,its structure was established and named as minaxin.     

New cassane butenolide hemiketal diterpenes from the marine creeper Caesalpinia bonduc and their antiproliferative activity

Two new cassane butenolides, caesalpinolide A (1) and B (2), epimeric at the hemiketal position were isolated from the marine creeper Caesalpinia bonduc. The structures were elucidated by the analysis of spectroscopic data and relative stereochemistry was assigned on the basis of ROESY correlations. Compounds 1 and 2 were found to inhibit MCF-7 breast cancer cell lines with IC₅₀ values of (μM) 12.8 and 6.1, respectively, along with the inhibition of endometrial and cervical cancer cell lines.     

Rearranged diterpenoids from the seeds of Caesalpinia sappan

Two new rearranged diterpenoids, tomocinol C (1) and spirocaesalmin C (2) were isolated from the seeds of Caesalpinia sappan. Their structures were elucidated based on comprehensive analysis of spectroscopic data, and their absolute configurations were established by single crystal X-ray crystallography.     

The new cassane-type diterpenes from Caesalpinia minax

Four new cassane-type diterpenes, Neocaesalpin S (1), Neocaesalpin T (2), Neocaesalpin U (3), and Neocaesalpin V (4) were isolated from Caesalpinia minax HANCE together with seven known compounds Neocaesalpin A (5), Neocaesalpin K (6), Neocaesalpin L (7), Neocaesalpin M (8), Neocaesalpin O (9), Neocaesalpin MP (10), and Magnicaesalpin (11). Their structures were elucidated on the basis of 1D- and 2D-NMR, MS, and circular dichroism (CD) analysis. Compounds 1-4 were tested against liver cancer (HepG-2) and breast cancer (MCF-7), and showed mild antiproliferative activity.