Perisomalien A,a new cytotoxic scalarane sesterterpene from the fruits of Periploca somaliensis

Abstract

The CHCl₃ fraction of MeOH extract of Periploca somaliensis (family Asclepiadaceae) fruits afforded a new scalarane sesterterpene, namely perisomalien A (1), along with lupeol acetate (2), β-amyrin (3), cycloart-23Z-ene-3β,25-diol (4), and β-sitosterol-3-O-β-D-glucopyranoside (5). Their chemical structures were established by various spectroscopic analyses, in addition to comparison with the formerly reported data. Moreover, the cytotoxic activity of these metabolites was assessed towards MCF-7, HepG2, and HCT-116 tumour cell lines using sulforhodamine B (SRB) assay. Compound 4 showed the most potent cytotoxic profile with IC₅₀ 9.0?µM towards MCF-7, compared to doxorubicin (IC₅₀ 0.18?µM). Also, 1 and 4 possessed the most potent effect towards HepG2 with IC₅₀s 26.7 and 25.9?μM, respectively. In addition, all tested compounds showed cytotoxic effects with IC₅₀ values ranging from 19.9 to 39.3?µM against HCT-116.     

A New Pregnane and a New Diphenylmethane from the Root Barks of Periploca sepium

A new polyoxygenated pregnane genin and a new diphenylmethane, along with five known pregnane derivatives, were isolated from the root barks of Periploca sepium. The structures of the new compounds were elucidated as (3β,14β)‐3,14‐dihydroxy‐21‐methoxypregn‐5‐en‐20‐one ( 1 ) and 2‐hydroxy‐5‐(2‐hydroxy‐4‐methoxybenzyl)‐4‐methoxybenzaldehyde ( 2 ) on the basis of spectroscopic methods, especially 2D‐NMR and MS analyses. The known compounds were identified by comparing their physical and spectroscopic data with those reported in the literature.     

A New Cardenolide and Two New Pregnane Glycosides from the Root Barks of Periploca sepium

A new cardenolide and two new pregnane glycosides, periplogenin 3‐[O‐β‐glucopyranosyl‐(1→4)‐β‐sarmentopyranoside] ( 1 ), (3β,20S)‐pregn‐5‐ene‐3,17,20‐triol 20‐[O‐β‐glucopyranosyl‐(1→6)‐O‐glucopyranosyl‐(1→4)‐β‐canaropyranoside] ( 2 ), and (3β,14β,17α)‐3,14,17‐trihydroxy‐21‐methoxypregn‐5‐en‐20‐one 3‐[O‐β‐oleandropyranosyl‐(1→4)‐O‐β‐cymaropyranosyl‐(1→4)‐β‐cymaropyranoside] ( 3 ), were isolated from the root barks of Periploca sepium Bge , together with seven related known compounds, periplogenin, xysmalogenin, (3β,20S)‐pregn‐5‐ene‐3,17,20‐triol, (3β,14β,17α)‐3,14,17‐trihydroxy‐21‐methoxypregn‐5‐en‐20‐one, (3β,20S)‐pregn‐5‐ene‐3,20‐diol 3‐β‐glucopyranoside 20‐β‐glucopyranoside, (3β,20S)‐pregn‐5‐ene‐3,20‐diol 3‐[O‐2‐O‐acetyl‐β‐digitalopyranosyl‐(1→4)‐β‐cymaropyranoside] 20‐[O‐β‐glucopyranosyl‐(1→6)‐O‐β‐glucopyranosyl‐(1→2)‐β‐digitalopyranoside], and (3β,20S)‐ pregn‐5‐ene‐3,20‐diol 20‐[O‐β‐glucopyranosyl‐(1→6)‐β‐glucopyranoside]. Their structures were elucidated on the basis of spectroscopic analyses.     

Five New Pregnane Glycosides from the Root Barks of Periploca sepium

Five new pregnane glycosides, perisepiumosides A–E ( 1 – 5 , resp.), along with the seven known constituents 6 – 12 , were isolated from the root barks of Periploca sepium Bge . (Asclepiadaceae), a traditional Chinese medicine used for the treatment of rheumatoid arthritis and wounds. Their structures were characterized on the basis of spectroscopic analyses.     

A New Eudesmanolide and a New Aromatic Derivative from Carpesium cernuun

Carpesium cernuun L. has long been used as chinese folk medicine for its anti-inflammatory, pain-relief, and detoxication properties1. Up to now, no phytochemical studies of Carpesium cernuun has been carried out. Here we report the structure elucidation of a new eudesmanolide 1 and a new aromatic derivative 2, which were obtained from this plant. Compound 1 was isolated as colorless gum, [(]+128.4 (c 0.43, CHCl3). Its EIMS revealed a molecular ion peak m/z 248. Together with the support …     

Three New Atisane Diterpenoids from Spiraea japonica

Three new atisane diterpenoids, spiratisanins A – C ( 1  –  3 , resp.), featuring a phenylacryloxyl substituted ent‐atisane skeleton, were isolated from Spiraea japonica together with two known atisine diterpene alkaloids, spiramine A ( 4 ) and spiradine F ( 5 ). The structures of these new compounds were elucidated as (5β,7α,8α,9β,10α,12α,16β)‐16‐hydroxyatisan‐7‐yl (2E)‐3‐phenylprop‐2‐enoate ( 1 ), (5β,7α,8α,9β,10α,12α,16α)‐16‐hydroxyatisan‐7‐yl (2E)‐3‐phenylprop‐2‐enoate ( 2 ), and (5β,8α,9β,10α,12α,16β)‐16‐hydroxyatisan‐20‐yl (2E)‐3‐phenylprop‐2‐enoate ( 3 ) on the basis of spectroscopic analysis.     

Three New Lycopodium Alkaloids from Phlegmariurus fargesii

Three new Lycopodium alkaloids, fargesiines A – C ( 1  –  3 , resp.), along with a known compound ( 4 ), were isolated from the whole plants of Phlegmariurus fargesii. Their structures were elucidated on the basis of spectroscopic data and chemical correlations. Compounds 1  –  4 were tested in an assay for acetylcholinesterase (AChE) inhibitory activity.     

Identification of Two New Phosphorylated Polyketides from a Brazilian Streptomyces sp. Through the Use of LC–SPE/NMR

Two new polyketide phosphate monoesters, phosdiecin A ( 1 ) and phosdiecin B ( 2 ), were isolated from a culture of the marine Streptomyces sp. SS99BA‐2 using the hyphenated technology LC–SPE/NMR. The compounds showed to be new representatives of an important class of antitumor antibiotic metabolites known as fostriecins. Their structures, including relative configuration attribution, were fully elucidated through extensive analyses of NMR and MALDI‐TOF/TOF HR‐MS data. Herein, the application of this system to isolate and identify the new compounds is described.     

A New Isoflavanol from the Fruits of Kotschya strigosa (Fabaceae)

The phytochemical investigation of the MeOH extract from fruits of Kotschya strigosa using repeated normal and reversed‐phase column chromatography and Sephadex LH‐20 chromatography led to the isolation and characterization of a new isoflavanol, named kotstrigoisoflavanol ( 1 ), together with three known compounds, diosmetin ( 2 ), β‐sitosterol ( 3 ), and the 3‐O‐β‐d‐glucopyranoside of β‐sitosterol ( 4 ). The antioxidant activity of crude extract, 1, and 2 was determined using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH˙) method. The crude extract (IC₅₀ 61.7 ± 0.2 μg/ml) and 2 (IC₅₀ 70.2 ± 0.1 μg/ml) showed moderate antioxidant activities, while 1 was weakly active (IC₅₀ 153.1 ± 0.1 μg/ml), as compared with the standard reference l ‐ascorbic acid (IC₅₀ 21.9 ± 0.0 μg/ml).     

Two New Flavonoids from Derris eriocarpa How

Two new flavonoids, 1 and 2 , together with two known flavonoids, tephrosin ( 3 ) and 12a‐hydroxy‐α‐toxicarol ( 4 ), were isolated from the whole herb of Derris eriocarpa How . The structures and absolute configurations of the new compounds were elucidated on the basis of their MS, NMR, and ECD data. The structures of the known compounds were established by extensive spectroscopic (MS, 1D‐ and 2D‐NMR) analyses and comparison with the literature data. All compounds were isolated from D. eriocarpa for the first time. Compound 3 showed modest inhibitory activities against the growth of human cancer cells HEL and A549 with the IC₅₀ values of 15.03 ± 0.62 and 13.27 ± 0.39 μm , respectively.     

Seven New Acyl Glycosides from Erycibe obtusifolia

Seven new acyl glycosides, benzyl 5‐O‐vanilloyl‐β‐d ‐apiofuranosyl‐(1→6)‐β‐d ‐glucopyranoside ( 1 ), 4‐hydroxy‐3‐methoxyphenyl 5‐O‐syringoyl‐β‐d ‐apiofuranosyl‐(1→6)‐β‐d ‐glucopyranoside ( 2 ), isopentyl 5‐O‐syringoyl‐β‐d ‐apiofuranosyl‐(1→6)‐β‐d ‐glucopyranoside ( 3 ), 3,4,5‐trimethoxyphenyl 5‐O‐sinapoyl‐β‐d ‐apiofuranosyl‐(1→6)‐β‐d ‐glucopyranoside ( 4 ), 6‐methoxy‐7‐[(6‐O‐sinapoyl‐β‐d ‐glucopyranosyl)oxy]coumarin ( 5 ), 6‐methoxy‐7‐[(2‐O‐sinapoyl‐β‐d ‐glucopyranosyl)oxy]coumarin ( 6 ), and isopentyl β‐d ‐apiofuranosyl‐(1→6)‐[5‐O‐syringoyl‐β‐d ‐apiofuranosyl‐(1→2)]‐β‐d ‐glucopyranoside ( 7 ), were isolated from Chinese folk herb Erycibe obtusifolia. Their structures were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, MS, and 1D‐ and 2D‐NMR techniques. Further, these compounds were evaluated against HCT‐8 (human colon carcinoma), Bel‐7402 (human liver carcinoma), BGC‐823 (human stomach carcinoma), A549 (human lung carcinoma), and A2780 (human ovarian carcinoma) cell lines, however, none of them exhibited a significant bioactivity (IC₅₀ > 10 μm ).     

A One Pot Synthesis of Dehydrohedione (DHH) from a Hedione® Precursor

Dehydrohedione (DHH) 1a was obtained via a one pot, three step, domino procedure in 54% overall yield from 2a , by treatment with CuBr₂, in MeOH at 65 °C. We demonstrated that the direct transformation of malonate derivative 2a into DHH 1a under CuX₂ Kochi's conditions goes preferentially through the pathway involving intermediates 2b / 2c and 7a , rather than 3a / 3b or 8a / 8b , essentially via α‐halogenation/dehydrohalogenation of the ketone moiety, both mediated by CuX₂, while in‐situ decarbomethoxylation is promoted by the resulting CuX in refluxing MeOH.     

Stachartins A – E,Phenylspirodrimanes from the Tin Mine Tailings‐Associated Fungus Stachybotrys chartarum

Eight phenylspirodrimane‐type analogues, including five new compounds, named stachartins A – E ( 1 , 3 , 6 – 8 ), were isolated from cultures of the tin mine tailings‐associated fungus Stachybotrys chartarum. Their structures were elucidated by spectroscopic methods including extensive 2D‐NMR techniques.     

Anti‐Inflammatory Activity of a Novel Acetylene Isolated from the Roots of Angelica tenuissima Nakai

Three polyacetylenes, one novel and two known, were isolated from the root of Angelica tenuissima. Using ¹H‐ and ¹³C‐NMR, COSY, HMBC, and HMQC, their structures were found to be (3R,8S)‐heptadeca‐1‐en‐4,6‐diyne‐3,8‐diol ( 1 ), falcarindiol ( 2 ), and oplopandiol ( 3 ). Absolute configurations of compound 1 were established using Mosher's esterification. In addition, the polyacetylenes ( 1 – 3 ) were evaluated for their anti‐inflammatory activity. Compounds 1 and 3 showed potent inhibitory activity against lipopolysaccharide‐induced nitric oxide (NO) production in RAW267.7 macrophage cells with IC₅₀ values of 4.31 and 5.06 μm, respectively. Compound 1 strongly inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)‐2 in a concentration‐dependent manner.     

Three New Pregnane Alkaloids from Pachysandra terminalis

Three new pregnane alkaloids, pachystermine C ( 1 ), pachysanamine A ( 2 ), and pachysanamine B ( 3 ), together with four known ones, pachystermine B ( 4 ), pachysamine A ( 5 ), (20S)‐20‐(dimethylamino)‐16α‐hydroxy‐3β‐(3′α‐isopropyl)lactam‐5α‐pregnan‐4‐one ( 6 ), and E‐salignone ( 7 ), were isolated from Pachysandra terminalis. The chemical structures of the new alkaloids were elucidated by spectroscopic methods. All the compounds were evaluated for their inhibitory activities against HL‐60, SMMC‐7721, A‐549, MCF‐7, and SW480 cell lines, some of the compounds showed stronger cytotoxicity for the test cell lines, especially compounds 2 , 3 , and 7 .     

Insignin A, A Novel C_21-Steroidal Aglycone from Biondia insignis

The genus Biondia having six species is exclusively distributed in China. But none of them was investigated in the aspect of phytochemistry before this work. From the view of plant taxonomy, the genus Biondia in the Trib. Asclepiadeae is close to the genus Cynanchum, and the plants of the latter mainly contain C21-steroids. In order to investigate whether the plants of the genus Biondia have C21-steroidal compounds and what kind of skeleton they may have, the whole plant of Biondia insigni…     

Clavulazols A and B,Two New Pyrazine Derivatives from Clavularia Viridis

Two new marine pyrazine derivatives, clavulazols A ( 4 ) and B ( 5 ), were isolated from ethyl acetate extract of the soft coral Clavularia viridis collected in Taiwan. The structures were determined on the basis of spectral analysis, especially 2D NMR as well as chemical conversion.     

Pseudonocardides A – G,New γ‐Butyrolactones from Marine‐derived Pseudonocardia sp. YIM M13669

Seven new γ‐butyrolactones, named pseudonocardides A – G ( 1  –  7 ), were isolated from the marine‐derived actinomycete strain Pseudonocardia sp. YIM M13669. Their structures were elucidated on the basis of spectroscopic data including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. The absolute configuration of 1 was determined by X‐ray crystallographic analysis of 1a (4‐bromobenzoate derivative of 1 ). The antibacterial activity against Mycobacterium smegmatis MC²155 and cytotoxicities of compounds 1  –  7 were evaluated in this study.     

Lyciumaside and Lyciumate: A New Diacylglycoside and Sesquiterpene Lactone from Lycium shawii

One new diacylglycoside named lyciumaside ( 1 ) and a new sesquiterpene lactone named lyciumate ( 2 ) were isolated from Lycium shawii Roem . & Schult . The structures of the two new compounds were elucidated based on 1D‐ (¹H‐ and ¹³C‐NMR and NOE) and 2D‐NMR (COSY, HSQC, and HMBC) spectroscopic techniques, and mass spectrometry (ESI‐MS). Preliminary evaluations demonstrated lyciumaside ( 1 ) possesses strong antioxidant activity with an IC₅₀ = 30 μg/ml (80% inhibition) while it was inactive in α‐glucosidase and urease enzymes assays.     

New Highly Oxidized Formamidobisabolene‐Derived Sesquiterpenes from a Hainan Sponge Axinyssa variabilis

Two new highly oxidized formamidobisabolene sesquiterpenes ( 1 and 2 ), together with seven known related analogues ( 3 – 9 ), were isolated from a Hainan sponge Axinyssa variabilis. Their structures were determined by extensive 1D‐ and 2D‐NMR and MS spectra analyses, and by comparison of their spectroscopic data with those of the related model compounds. The plausible biosynthetic relationship between compounds 1 – 9 has also been described.