Two new triterpenoids from the fungus Diplodia cupressi

Abstract

One new pentanortriterpenoid, 23,24,25,26,27-pentanorlanost-7,9(11)-dien-3β,22-diol (1), one new triterpenoid, lanost-8-en-3β,22S,23S-triol (2), together with the known triterpenoid, 23,24,25,26,27-pentanorlanost-8-en-3β,22-diol (3), were obtained from culture of the fungus Diplodia cupressi associated with the moss Polytrichum commune. The structures of the new compounds were elucidated by extensive spectroscopic techniques including HR-ESIMS and 1?D and 2?D NMR experiments. The cytotoxicity of these compounds against human cancer cell lines (A549, Hep G2, Hepa 1c1c7, and Hela) was evaluated and compound 2 exhibited weak inhibitory activity with IC₅₀ value of 35.0?±?2.3?μM against the proliferation of the Hepa 1c1c7 cells.     

Five New Triterpenoids from the Roots of Kadsura coccinea

A phytochemical investigation of an EtOH extract of the roots of Kadsura coccinea (Lem .) A. C. Sm . furnished five new lanostane‐type triterpenoids, coccinone A ( 1 ), coccinone B ( 2 ), coccinone C ( 3 ), coccinone D ( 4 ), and coccinilactone B ( 5 ). Their structures were determined based on spectroscopic analyses, including 2D‐NMR experiments and HR‐MS techniques.     

Bidesmosidic Oleanane Saponins from Xerospermum noronhianum

Three new oleanane‐type triterpenoid saponins, 3‐O‐(α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐fucopyranosyl)‐28‐O‐{[α‐L ‐rhamnopyranosyl(1→2)] [β‐D ‐fucopyranosyl(1→6)]‐β‐D ‐glucopyranosyl} oleanolic acid ( 1 ), 3‐O‐[α‐L ‐rhamnopyranosyl(1→3)‐β‐D ‐fucopyranosyl]‐28‐O‐[α‐L ‐rhamnopyranosyl(1→4)‐β‐D ‐glucopyranosyl] oleanolic acid ( 2 ), and 3‐O‐{α‐L ‐rhamnopyranosyl(1→2)‐[3′,4′‐diacetoxy‐β‐D ‐fucopyranosyl]}‐28‐O‐[α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐glucopyranosyl] oleanolic acid ( 3 ) have been isolated from the stems of Xerospermum noronhianum. The structures of the saponins were determined as a series of bidesmosidic oleanane saponins based on spectral evidence. The anticholinesterase activity of the saponins 1 – 3 was also evaluated.     

Euphatexols A and B,two unusual euphane triterpenoids from the latex of Euphorbia resinifera

Two unusual euphane triterpenoids, named euphatexols A (1) and B (2), were isolated from the latex of Euphorbia resinifera. Their structures were elucidated based on the extensive analysis of spectroscopic data (HRMS, 1D and 2D NMR). Compound 1 possesses a rare tetrahydrofuran ring formed via C-1 and C-11, which is firstly reported in euphane triterpenoids. Compound 2 represents an unusual 27-nor-euphane triterpenoid. Moreover, compounds 1 and 2 showed significant cytotoxic activities against HepG2 cells with 87.0% and 87.4% inhibition rate at 1 μM, respectively.     

Structure-activity relationship of Triterpenes and derived Glycosides against cancer cells and mechanism of apoptosis induction

Triterpenoids possess a wide range of biological effects. Here, the cytotoxic activities of 55 triterpenes and derived glycosides against BEL-7404 and SGC-7901 cells were assessed, and structure-activity relationships were analysed accordingly. Nine of them effectively inhibited the two cell lines. In particular, compounds 49 and 52 inhibited BEL-7404 cells as efficiently as 5’-fluorouracil (IC₅₀ values 0.46 and 1.48, respectively). Moreover, we found that compounds 49 and 52 induced apoptosis in BEL-7404 cells. Indeed, DNA fragmentation assay showed a time-dependent degradation of DNA after treatment of cells with compounds 49 and 52. In addition, Bax gene expression levels were increased after treatment with these compounds, in a concentration-dependent manner. Taken together, our findings suggested that compounds 49 and 52 induce apoptosis in BEL-7404 cells by upregulating the Bax gene without affecting Bcl-2 gene expression.     

Highly Acetylated Lanostane‐Type Triterpenoids from Coprinus cinereus 120

Two new highly acetylated lanostane‐type triterpenoids, coprinacin A ( 1 ) and coprinacin B ( 2 ), were isolated from the basidiomycetous strain Coprinus cinereus 120. The chemical structures of 1 and 2 were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments and FT‐ICR‐MS, and their in vitro cytotoxic activities against the human‐tumor cell line HeLa were established as modest.     

A New 30‐Noroleanane Saponin from Wedelia chinensis

A novel 30‐nortriterpenoid saponin, (3β)‐3‐hydroxy‐30‐noroleana‐12,20(29)‐dien‐28‐oic acid 3‐(β‐D ‐glucopyranosiduronic acid 6‐methyl ester) ( 1 ), and a known compound, (3β)‐oleanolic acid 3‐(β‐D ‐glucopyranosiduronic acid 6‐methyl ester) ( 2 ), were isolated from the aerial parts of Wedelia chinensis. The structures were established by their spectral data including ¹H‐ and ¹³C‐NMR, ¹H,¹H‐COSY, HMBC, HSQC, NOESY, and HR‐FAB‐MS data.     

Five New Tetranortriterpenoids from the Seeds of Toona ciliata

Five new tetranortriterpenoids, toonaciliatones B–F ( 1 – 5 , resp.), together with four known compounds, dihydrocedrelone ( 6 ), cedrelone ( 7 ), 6α‐acetoxyazadirone ( 8 ), and 6α‐acetoxy‐14β,15β‐epoxyazadirone ( 9 ), were isolated from the seeds of Toona ciliata. Their structures were elucidated by spectroscopic methods, including 1D‐ and 2D‐NMR spectroscopy.     

Pentacyclic Triterpenoid Saponins from Silene viscidula

Three new pentacyclic triterpenoid saponins, viscidulosides A and B ( 1 and 2 , resp.), and silenoviscoside D ( 3 ), were isolated from the roots of Silene viscidula, together with two known saponins, sinocrassulosides VIII and IX ( 4 and 5 , resp.). Their structures were elucidated by spectroscopic data and chemical methods. Compounds 1 / 2 and 4 / 5 were two inseparable mixtures, which are glycosides of quillaic acid whose fucose residue is acylated by (E)‐ or (Z)‐4‐methoxycinnamic acid.     

Triterpenoids from the Stems of Schisandra glaucescens

Two new lanostane triterpenoids, schiglauzic acid ( 1 ) and schiglaucyclozic acid ( 2 ), together with two known ones, anwuweizic acid ( 3 ) and manwuweizic acid ( 4 ), were isolated from the stems of Schisandra glaucescens. Their structures were determined on the basis of extensive spectroscopic methods, including two‐dimensional NMR techniques, and were further confirmed by X‐ray crystallographic analysis.