A new natural nucleotide and other antibacterial metabolites from an endophytic Nocardia sp.

Nine compounds were isolated from Nocardia sp. YIM 64630, and their structures were elucidated as 5′-O-acetyl-2′-deoxyuridine (1), 22E,24R-5α,6α-epoxyergosta-8(14),22-diene-3β,7α-diol (2), 22E,24R-5α,6α-epoxyergosta-8,22-diene-3β,7α-diol (3), 22E,24R-ergosta-7,22-diene-3β,5α,6β-triol (4), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (5), 4′,5,6-trihydroxy-7-methoxyisoflavone (6), 2,4,4′-trihydroxy-deoxybenzoin (7), methyl [4-hydroxyphenyl]acetate (8) and daidzein by extensive spectroscopic analyses. Compound 1 was isolated from natural resources for the first time. The antimicrobial and antioxidant activities of compounds 1–8 were investigated.     

Antibacterial sphingolipid and steroids from the black coral Antipathes dichotoma

From the black coral Antipathies dichotoma, a sphingolipid (2S*,3S*,4E,8E)-2N-[tetradecanoyl]-4(E),8(E)-icosadiene-1,3-diol (1) and a steroid (22E)-methylcholesta-5,22-diene-1α,3β,7α-triol (2) were isolated. Other known compounds, 3β,7α-dihydroxy-cholest-5-ene (3), (22E,24S),5α,8α-epidioxy-24-methylcholesta-6,22-dien-3β-ol (4) and (22E,24S),5α,8α-epidioxy-24-methylcholesta-6,9(11),22-trien-3β-ol (5). The structures were established on the basis of NMR spectroscopic analysis and comparison with literature. The antibacterial activity of five compounds was evaluated.     

云南美登木内生真菌Phomopsis sp. Lz42的化学成分

从云南美登木内生真菌Phomopsis species Lz42的琼脂平板发酵物中分离得到2个倍半萜和5个麦角甾醇类化合物(1~7), 其中化合物1和2为新化合物. 应用波谱技术确定其结构为4-Deacetyl-10-oxo-dihydrobotrydial(1)和麦角甾-6,22-二烯-5α,8α-环二氧-3-甲酸酯(2).     

Studies on the Constituents of Ganoderma Lucidum

The methanolic extract of fruit bodies of cultivated Ganoderma lucidum was separated by silica gel column chromatography and preparative thin-layer chromatography to give ten compounds. On the basis of spectral analysis, chemical procedures and gas chromatography, d-mannitol (1), ergosta-7, 22-dien-3β-yl palmitate (2), ergosterol (3), ergosta-7, 22-dien-3β-ol (4), 5α-lanosta-7,9(11),24-trien-3β,26-diol (5), ergosterol peroxide (6), 24,25,26-trihydroxy-5α-lanosta-7,9(11)-dien-3-one (7), 5α-lanosta-7,9(11)-dien-3β,24,25,26-tetraol (8) and 8,9-epoxyergosta-5,22-dien-3β,15-diol (9) were identified. Among these compounds, 8,9-epoxyergosta-5,22-dien-3β,15-diol was first separated from Ganoderma lucidum.     

Chemical constituents from the roots of Xanthium sibiricum

Xanthium sibiricum patrin ex Widder (Compositae) is an annual herb which grows all around China. Chemical investigations of its roots resulted in the identification of 15 compounds: stigmast-4-en-6β-ol-3-one (1), β-sitostenone (2), β-sitosterol (3), nonadecanoic acid (4), 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (5), scopoletin (6), Jatrocin B (7), (±)syringaresinol (8), 9,9'-O-di-(E)-feruloyl-(-)-secoisolariciresinol (9), cleomiscosin A (10), cleomiscosin C (11), N-trans-feruloyl tyramine (12), daucosterol (13), 5-methyluracil (14) and uracil (15). Structures were elucidated by spectroscopic (NMR and MS) methods and confirmed by comparing with reference samples and literature data. Compounds 1-2, 4-12, 14, and 15 were isolated from this genus for the first time, while this is the first report of coumarinolignoids in the Compositae family, and coumarinoligoids could be considered as valuable chemotaxonomic markers for the plant.     

Chemical constituents from Aphanamixis grandifolia

(23E)-25-Methylcycloart-23-en-3β-ol (1), a cycloartane-type triterpenoid featuring an unusual skeleton of 31 carbon atoms, (17E)-cycloart-17,26-dien-3β-ol (2), a new cycloartane-type triterpenoid, and the other two new compounds 4R-hydroxy-4-(9S-hydroxy-12-methylhexan-6-yl)-3-methylcyclopent-2-enone (6) and 7-hydroxy-5-(2'-hydroxy-4',5'-dimethoxyphenyl)-2-methoxy-6-methyl-1,4-naphthoquinone (7), together with three known cycloart-3β-ol triterpenoids (3-5) were isolated from aerial parts of Aphanamixis grandifolia. Their structures were elucidated by spectroscopic analysis, and that of 1 was confirmed by single-crystal X-ray diffraction. The absolute configuration of two carbon stereocenters of compound 6 was determined to be 4R,9S by means of circular dichroism (CD) and auxiliary chiral α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA) derivatives, respectively. The compound 3 exhibited significant cytotoxicities against HL-60, Hep G2 and HeLa, and compounds 1, 2, 5, 6 and 7 exhibited modest cytotoxicities. No activity of compound 4 could be due to the absence of the hydroxyl group at C-24.     

Identification de stérols à chaînes latérales courtes dans l′éponge Damiriana hawaiiana

Identification of short side chain sterols in the sponge Damiriana hawaiiana The steroidal composition of the sponge Damiriana hawaiiana is examined. Twenty-seven components are identified. In addition to the C₂₆-C₂₉, Δ⁵-mono and diunsaturated sterols, the sponge contains sterols without side-chain: androsta-5, 16-dien-3β-ol( 1 ), androst-5-en-3β-ol( 2 ); sterols with a non-functionalized side-chain consisting of two, three, four, five and six carbon atoms: pregna-5, 20-dien-3β-ol( 5 ), pregn-5-en-3β-ol( 6 ), 23, 24-bisnor-chola-5, 20-dien-3β-ol( 7 ), 23, 24-bisnor-chol-5-en-3β-ol( 8 ), 24-nor-chol-5-en-3β-ol( 10 ), chol-5-en-3β-ol( 11 ), 26, 27-bisnor-cholest-5-en-3β-ol( 12 ), and sterols possessing a short oxygenated side-chain such as 3β-hydroxy-androst-5-en-17-one( 3 ), androst-5-en-3β, 17β-diol( 4 ) and 3β-hydroxy-26, 27-bisnor-22-trans-cholesta-5, 22-dien-24-one( 14 ). The probable biological or dietary origin rather than artifact production of these hitherto undescribed components from marine sources is supported by their relatively high concentration and their relative proportions, both very different from those expected for autoxidation.     

Steroids and an oxylipin from an algicolous isolate of Aspergillus flavus

A new oxylipin, (8E,12Z)-10,11-dihydroxyoctadeca-8,12-dienoic acid (1), a new steroid, 3β,4α-dihydroxy-26-methoxyergosta-7,24(28)-dien-6-one (2), and four known steroids, episterol (3), (22E,24R)-ergosta-7,22-dien-3β,5α,6α-triol (4), (22E,24R)-ergosta-5,22-dien-3β-ol (5), and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (6), were isolated from the cultures of Aspergillus flavus, an endophytic fungus isolated from the marine red alga Corallina officinalis. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. 1 and 2 exhibited low activity to inhibit acetylcholinesterase and no activity against plant pathogenic fungi Colletotrichum lagenarium and Fusarium oxysporum.     

A new antimicrobial sesquiterpene isolated from endophytic fungus Cytospora sp. from the Chinese mangrove plant Ceriops tagal

Abstract

Chemical examination of Chinese mangrove Ceriops tagal endophytic Cytospora sp., yielded a new biscyclic sesquiterpene seiricardine D (1), and eight known metabolites, xylariterpenoid A (2a), xylariterpenoid B (2b) and regiolone (3) 4-hydroxyphenethyl alcohol (4), (22E, 24R)5, 8-epidioxy-5α, 8α-ergosta-6,22E-dien-3ß-ol (5), (22E, 24R)5, 8-epidioxy-5α, 8α-ergosta-6,9(11), 22-trien-3 ß-ol (6), ß-sitosterol (7) and stigmast-4-en-3-one (8). These structures were unambiguously elucidated on the basis of extensive NMR spectroscopic and mass spectrometric analyses. The antimicrobial activities of compounds 1–8 and their effects on a panel of plant and human pathogens were evaluated.     

Polyoxygenated ergostane-type sterols from the liquid culture of Ganoderma applanatum

A new polyoxygenated ergostane-type sterol, 3β,5α,6β,8β,14α-pentahydroxy-(22E,24R)-ergost-22-en-7-one (1), has been isolated from the liquid culture of the basidiomycete Ganoderma applanatum together with four known sterols, 3β,5α,9α-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one (2), ergosterol peroxide (3), 6-dehydrocerevisterol (4) and cerevisterol (5). Two of these sterols (2, 4) are reported to have been isolated from this species for the first time. The structures of these compounds were determined by chemical and spectroscopic analyses, including 1D- and 2D-NMR, as well as by comparison of their spectroscopic data with those reported in the literature.     

Steroid alcohols from the ascidianHalocynthia aurantium

The total sterols have been isolated fromHalocynthia aurantium by column chromatography on silica gel. The following steroid alcohols have been identified in it with the aid of GLC, GLC-MS, and¹H NMR: 5α-cholestan-3β-ol, 24ξ-methylcholestan-3β-ol, 24ξ-ethylcholestan-3β-ol, 4ξ-methyl-24ξ-ethyl-5α-cholestan-3β-ol, cholest-5-en-3β-ol, 24ξ-methylcholest-5-en-3β-ol, 24ξ-ethylcholes-5-en-3β-ol, 5α-cholest-22-en-3β-ol, 24-nor-5α-cholest-22-en-3β-ol, cholesta-5,22-dien-3β-ol, 24ξ-methylcholesta-5,22-dien-3β-ol, 24-norcholesta-5,22-dien-3β-ol, 24-ethylcholesta-5,24(28)-dien-3β-ol, and 24-methylcholesta-5,24(28)-dien-3β-ol.     

Antimicrobial metabolites from the endophytic fungus Pichia guilliermondii isolated from Paris polyphylla var. yunnanensis

Three steroids and one nordammarane triterpenoid were isolated for the first time from the endophytic fungus Pichia guilliermondii Ppf9 derived from the medicinal plant Paris polyphylla var. yunnanensis. By means of physicochemical and spectrometric analysis, they were identified as ergosta-5,7,22-trienol (1), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (2), ergosta-7,22-dien-3β,5α,6β-triol (3), and helvolic acid (4). Both micro-dilution-colorimetric and spore germination assays were employed to evaluate their antimicrobial activity. Among them, helvolic acid (4) exhibited the strongest antibacterial activity against all test bacteria, with MIC values ranging from 1.56 μg/mL to 50 μg/mL, and IC(50) values from 0.98 μg/mL to 33.19 μg/mL. It also showed strong inhibitory activity on the spore germination of Magnaporthe oryzae with an IC(50) value of 7.20 μg/mL. Among the three steroids, 5α,8α-epidioxyergosta-6,22-dien-3β-ol (2) exhibited relatively strong antimicrobial activity. The results suggest that the endophytic fungus Pichia guillermondii Ppf9 could be a candidate for producing helvolic acid, and the metabolites from this fungus could be potentially developed as antimicrobial agents in the future.     

Isolation,Structure Determination and Synthesis of New Acetylenic Steroids from the Sponge Calyx nicaaensis

Two acetylenic steroids, cholest-5-en-23-yn-3β-ol ( 5 ) and 26,27-dinorcholest-5-en-23-yn-3β-ol ( 3 ), and another unsaturated steroidalcohol, stigmasta-5,23-dien-3β-ol ( 7 ), were isolated from the sponge Calyx nicaaensis. The structures of these two acetylenic steroids were established by synthesis. Several attempts to synthesize the marine steroids alcohol calysterol ( 1 ), with a cyclopropene-containing side chain, starting from cholest-5-en-23-yn-3β-ol are also recorded. Addition of ethyl-diazo-acetate to the triple bond was performed, but the reduction to the methyl derivative yielded decomposition products.     

Use of n-lithioethylenediamine in the double bond isomerization and degradation of sterol side chains

Double bond isomerization of stigmasterol ((24S)-24-ethylcholesta-5,22-dien-3β-ol) with N-lithioethy-lenediamine produced stigmasta-5,17(20)-dien-3β-ol, stigmasta-5,20(22)-dien-3β-ol, stigmasta-5,23-dien-3β-ol and stigmasta-5,24-dien-3β-ol. Some starting material was also present in the isomerization mixture along with a small amount of stigmast-5-en-3β-ol. Similar treatment of 3α,5-cyclo-6β-methoxystigmast-22-en (stigmasterol i-methyl ether) followed by ozonization and removal of the ring A-protecting group yielded predominantly 3β-hydroxy-androst-5-en-17-one and 3β-hydroxypregn-5-en-20-one. The isomerization products of fucosterol (24-ethylcholesta- 5, 24(28)E-dien-3β-ol) and 23,24-bisnorchola-5,20-dien-3β-ol are also reported.     

NMR spectral assignments of two sterols from a soft coral Sinularia brassica

Two new steroids, named 4α,22-dimethyl-Cholest-22-en-3β-ol (1) and 4α-methyl-Cholest-7,22-dien-3β-ol (2), along with two known steroids, were isolated from the soft coral Sinularia brassica. The structures of the new compounds were determined on the basis of extensive spectroscopic data (MS, (1)H and (13)C NMR, (1)H-(1)H COSY, (13)C-(1)H COSY, HMBC and NOESY) analysis.     

A new pyrrolidine derivative and steroids from an algicolous Gibberella zeae strain

A new pyrrolidine derivative, 3-hydroxy-5-(hydroxymethyl)-4-(4'-hydroxyphenoxy)pyrrolidin-2-one (1), and eight known steroids, (22E,24R)-7beta,8beta-epoxy-3beta,5alpha,9alpha-trihydroxyergosta-22-en-6-one (2, a reassigned structure of (22E,24R)-5alpha,6alpha-epoxy-3beta,8beta,14alpha-trihydroxyergosta-22-en-7-one), (22E,24R)-3beta,5alpha,9alpha-trihydroxyergosta-7,22-dien-6-one (3), (22E,24R)-3beta,5alpha-dihydroxyergosta-7,22-dien-6-one (4), (22E,24R)-ergosta-7,22-dien-3beta/,5alpha,6beta-triol (5), (22E,24R)-ergosta-5,22-dien-3beta-ol (6), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), and (22E,24R)-1(10 --> 6)-abeo-ergosta-5,7,9,22-tetraen-3alpha-ol (9), were isolated from the cultures of Gibberella zeae, an endophytic fungus isolated from the marine green alga Codium fragile. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. Compound 1 showed cytotoxicity against A-549 and BEL-7402 cell lines.     

A new 5α,8α-epidioxysterol with immunosuppressive activity from the South China Sea soft coral Sinularia sp.

Abstract

A new 5α,8α-epidioxysterol, namely yalongsterol A (1), along with two known related steroids 5α,8α-epidioxy-24-methyl-cholesta-6,24(28)-dien-3β-ol (2) and (22E,24S)-5α,8α-epidioxy-24-methyl-cholesta-6,22-dien-3β-ol (3), were isolated from the South China Sea soft coral Sinularia sp. Their structures were established by extensive spectroscopic analyses and comparisons of the spectral data with those reported in the literature. In bioassay, compounds 1–3 showed moderate immunosuppressive activities against T and/or B lymphocyte cells with IC₅₀ values ranging from 19.30 to 59.49 μM, and low cytotoxicity on murine splenocytes with CC₅₀ values ranging from 40.88 to 62.29 μM.

     

Asterosaponins isolated from the starfish Asterias amurensis

Three new asterosaponins 1-3 and four known saponins 4-7 have been isolated from the starfish Asterias amurensis LüTKEN. By means of high magnetic field 1D- and 2D-NMR ((1)H-(1)H correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY)) and MS analyses, the chemical structures of new compounds were determined to be 6α-O-[β-D-fucopyranosyl-(1→2)-β-D-galactopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-quinovopyranosyl-(1→3)-β-D-galactopyranosyl]-5α-chol-9(11)-en-23-one-3β-yl sodium sulfate (1), 6α-O-[β-D-fucopyranosyl-(1→2)-β-D-galactopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-quinovopyranosyl-(1→3)-β-D-galactopyranosyl]-5α-cholesta-9(11),24-dien-23-one-3β-yl sodium sulfate (2), and 6α-O-[β-D-fucopyranosyl-(1→2)-β-D-galactopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-quinovopyranosyl-(1→3)-β-D-galactopyranosyl]-5α-cholest-9(11)-en-23-one-3β-yl sodium sulfate (3). In addition, the NMR data for known saponins 4-7 were completely assigned by extensive 2D-NMR analysis without chemical degradation.     

Constituents of Fruit Bodies of Tramete orientalis

A known sterol, 5α,6α-epoxy-5α-crgosta-8(14),22E-diene-3β,7α-diol ( 1 ), and two new sterols, 5α,6α-epoxy-3β,8β,14α-trihydroxy-5α-ergost-22E-en-7-one ( 2 ), (3α,5α),(8β,11β)-diepidioxy-ergost-22E-en-12-one ( 3 ), were isolated and characterized from dried fruit bodies of Trametes orientalis. Their structures were elucidated according to spectral methods.     

Synthesis of the putative marine sterols [24R]- and [24S]-23,24-dimethyl-5α-cholest-23(29)-en-3β-ol.

The synthesis and stereochemistry of [24R]- and [24S]-23,24-dimethyl-5α-cholest-23(29)-en-3β-ol is reported; both isomers are different from a natural marine sterol to which the structure had been assigned.