Four 14(13→12)‑Abeolanostane Triterpenoids with 6/6/5/6‑Fused Ring System from the Roots of Kadsura coccinea

Four new rearranged 6/6/5/6-fused lanostane-type triterpenoids,kadcoccitanes A-D(1-4),were isolated from the roots of Kadsura coccinea,and their structures were mainly elucidated by comprehensive analysis of their spectroscopic data.Additionally,the structure of 1 was ambiguously verifed by single-crystal X-ray difraction,while the structure of 2,which features a novel 8,16-epoxy motif,was validated by quantum chemical calculation of NMR parameters and ECD spectrum.Moreover,1 and 4 were found to exhibited anticoagulant activity,while 3 and 4 were found to possess anti-platelet aggregation activity.

Two New Compounds from Schisandra propinqua var.propinqua

Schisanpropinoic acid(1),a new bergamotane sesquiterpenoid,and schisanpropinin(2),a new tetrahydrofuran lignan with a rare epoxyethane unit,were identified from the stems and leaves of Schisandra propinqua var.propinqua.Their structures were determined based on comprehensive spectroscopic and mass spectrometric analysis.The absolute configuration of 1 was determined by X-ray analysis.Compounds 1 and 2 were tested for their cytotoxic activity against five human tumor cell lines.

Four new indole alkaloids from Plantago asiatica

Four new indole alkaloids,plasiaticines A-D(1-4),together with two known ones,were isolated from the seeds of Plantago asiatica.The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data.All compounds were tested for their cytotoxic activity,and all compounds except 4 were tested for their acetylcholinesterase(AChE)inhibitory activities.

Two Natural ent-kauranoids as Novel Wnt Signaling Inhibitors

Constitutively active Wnt signaling frequently occurs in most colon cancers.Therefore,inhibitors of Wnt signaling pathway could provide rational therapeutic effects for colorectal malignancy.Within this paper,we identified two inhibitors of Wnt signaling pathway,rabdoternin B and maoecrystal I from a natural ent-kauranoid library by a dualluciferase reporter gene assay.The two compounds inhibited Wnt signaling pathway in a concentration-dependent manner and exhibited selective cytotoxicity toward a number of colon carcinoma cell lines SW480,HCT116,and HT29,with only weak cytotoxicity towards the normal colonic epithelial cell line CCD-841-CoN.Rabdoternin B and maoecrystal I treatment induced G2/M phase arrest efficiently in SW480 cells as revealed by flow cytometry analysis.A further study found that maoecrystal I decreased the expression of Wnt signaling target genes,including c-myc,cyclin D1,survivin and Axin2 in colon cancer cells.Collectively our data suggests that rabdoternin B and maoecrystal I are novel inhibitors of canonical Wnt signaling pathway and may possess potentials for colon cancer therapy.

Secondary Metabolites from the Endophytic Fungus Xylaria sp.hg1009

A detailed chemical investigation of the secondary metabolites produced by the endophytic fungus Xylaria sp.isolated from the stems of Isodon sculponeatus afforded six new compounds,xylariahgins A-F(1-6),two new natural products(7 and 8),along with two known compounds(9 and 10)(Fig.1).The structures of all compounds were unambiguously established by analyzing their spectroscopic data or referring to pertinent literature.Compounds 1-8 were tested for their cytotoxic activity against five human tumor cell lines.

Four new diterpenoids from Isodon eriocalyx var.laxiflora

Four new diterpenoids,laxiflorins S-V(1-4),bearing four different types,and one known compound,laxiflorin O(5),were isolated from Isodon eriocalyx var.laxiflora.Compound 1 was the first example of ent-kauranoids bearing a unique C_(24) carbon framework and compound 4 was the first example of 3,4-seco-ent-abietane diterpenoids from the Isodon genus.Their structures were determined by spectroscopic methods(UV,IR,MS,NMR).

Tangutidines A-C,Three Amphoteric Diterpene Alkaloids from Aconitum tanguticum

Three new diterpene alkaloids,tangutidines A-C(1-3),and four known alkaloids(4-7)were isolated from the whole plant of Aconitum tanguticum,from which amphoteric diterpene alkaloids(1-3)were obtained for the first time.The structures of 1-3 were elucidated by detailed interpretation of spectroscopic data,including MS and NMR data.All of them were evaluated for their cytotoxic activities.

Four new lignans from the leaves and stems of Schisandra propinqua var.sinensis

Four new tetrahydrofuran lignans,schpropinrins A-D(1-4),together with five known ones,were isolated from the leaves and stems of Schisandra propinqua var.sinensis.Their structures,including absolute configurations,were characterized by means of spectroscopic analysis and ECD calculation.Compounds 1-4 featured a ketal or hemiketal substructure at C-7 and all of the isolates were tested for their anti-HIV integrase activity.

Three new nortriterpenoids from Schisandra wilsoniana and their anti-HIV-1 activities

Three new highly oxygenated nortriterpenoids,wilsonianadilactones D-F(1-3),were isolated from the leaves and stems of Schisandra wilsoniana.Their structures were established by means of spectroscopic analysis.Compounds 1-3 showed weak anti-HIV-1 activity with the therapeutic index(TI)values(CC50/EC50)greater than 8.16,14.7,and 17.5,respectively.

Arthrinins E-G, Three Botryane Sesquiterpenoids from the Plant Endophytic Fungus Arthrinium sp. HS66

Arthrinins E-G(1-3),three new sesquiterpenoids possessing non-isoprenoid botryane skeleton,were isolated from the fermentation of an endophytic fungus named Arthrinium sp.HS66 which colonized in the stems of Isodon xerophilus.Their structures were determined by extensive spectroscopic methods.Furthermore,the structure of 1 was unambiguously confirmed by X-ray diffraction,while those of 2 and 3 were verified through quantum chemical calculation of NMR data and ECD spectra.

Two new neolignans from Manglietia insignis

Two new neolignans,manneoinsigins A(1)and B(2),together with four known lignans,were isolated from the leaves and stems of Manglietia insignis.The new compounds were established on the basis of extensive spectroscopic analyses.All compounds except 2 were tested for their cytotoxic activity.Compound 3 showed weak cytotoxic activity against the HL-60 human tumor cell line with the IC50 value of 23.5μM.

Lignans and sesquiterpenoids from the stems of Schisandra bicolor var. tuberculata

A pair of new tetrahydrofuran lignan enantiomers,(±)-schibiculatin A[(±)-1],a new enedione lignan,schibiculatin B(2),two new cadinane-type sesquiterpenoids,schibiculatins C(3)and D(4),along with two known seco-cadinane-type sesquiterpenoids(5 and 6)and seven known miscellaneous lignans(7-13)were isolated from the stems of Schisandra bicolor var.tuberculata.The structures of 1-4 were elucidated by comprehensive analysis of their spectro-scopic data,quantum chemical calculations,as well as single-crystal X-ray diffraction.A few isolated compounds were tested for their protective activities against corticosterone-induced apoptosis in PC12 cells.Among them,compounds 5 and 6 showed moderate activities.

Isorosthornins A-C,new ent-kaurane diterpenoids from Isodon rosthornii

Three new ent-kauranoids,isorosthornins A-C(1-3),and a new natural product,dihydroponicidin(4),together with five known ones were isolated from the aerial parts of Isodon rosthornii.The structures were determined by means of extensive spectroscopic analysis.All diterpenoids isolated were evaluated for their cytotoxicity against HL-60,SMMC-7721,A-549,MCF-7,and SW480 cell lines,and compounds 5 and 7 showed significant inhibitory effects on all cell lines.

Three minor new compounds from the aerial parts of Leonurus japonicus

Phytochemical investigation of the aerial parts of Leonurus japonicus led to the isolation of one new labdane diterpenoid, leojaponin D （1） and two new ionone derivatives, leojaponones A and B （2 and 3）, together with seven known diterpenoids （4-10）. Their structures were elucidated by extensive 1D and 2D NMR spectroscopic data and by comparison with data reported in the literature. Selected isolates were evaluated their effects on lurkat IL2 secretino.

Three new diterpenoids from Leonurus japonicus

Phytochemical investigation of the aerial parts of Leonurus japonicus led to the isolation of one unusual clerodane diterpenoid,leojaponin A（1）,characterized by a C4–C7oxa-bridge,and two new labdane diterpenoids,leojaponins B（2） and C（3）.The structures of these new compounds were determined based on extensive 1D and 2D NMR spectroscopic data.To the best of our knowledge,compound 1 is the first clerodane diterpenoid obtained from Leonurus.japonicus.All of them were evaluated for their cytotoxicity.

Two new guaianolide-type sesquiterpenoids from Kadsura interior

Received 22 November 2012 Received in revised form 25 December 2012 Accepted 2B December 2012 Available online 4 February 2013

Pestaloamides A and B,two spiro-heterocyclic alkaloid epimers from the plant endophytic fungus Pestalotiopsis sp.HS30

Pestaloamides A and B(1 and 2),two novel alkaloids featuring an unprecedented spiro[imidazothiazoledione-alkylidenecyclopentenone]scaffold,were obtained from the cultures of an endophytic fungus Pestalotiopsis sp.HS30 which inhabited the stems of Isodon xerophilus.Their planar structures and absolute configurations were fully determined by extensive spectroscopic analysis and X-ray crystallography.In addition,both compounds 1 and 2 showed the latent tumor immunotherapy activity through markedly promoting the cell surface engagement of NKG2 D ligands involving MICA/B and ULBP1 in HCT116 cells.

6,7-seco-ent-Kaurane diterpenoids from Isodon sculponeatus and their bioactivity

One new 6,7-seco-ent-kaurane diterpenoid, sculponin T （1）, was isolated from the aerial parts of lsodon sculponeatus, along with four known analogs, sculponeatin J （2）, sculponeatin K （3）, sculponeatin C （4）, and sculponeatin Q （5）. Their structures were elucidated by extensive spectroscopic analysis and by comparison with data reported in the literature. Significant cytotoxic activity was observed for compound 2 against five human tumor cell lines with IC50 values ranging from 1.8 μmol/L to 3.3 μmol/L, and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with IC50 value of 3.3 μmol/L.