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1.
Four new patchoulol derivatives, 8α,9α‐dihydroxypatchoulol ( 1 ), 3α,8α‐dihydroxypatchoulol ( 2 ), 6α‐hydroxypatchoulol ( 3 ), and 2β,12‐dihydroxypatchoulol ( 4 ), were isolated from the aerial part of Pogostemon cablin (Labiatae), together with nine known compounds, sesquiterpenoids 5 – 8 and flavonoids 9 – 13 . Their structures were elucidated by detailed spectroscopic analysis, using 1D‐ and 2D‐NMR techniques.  相似文献   

2.
Eight new benzoylated gentisyl alcohol (=2‐(hydroxymethyl)benzene‐1,4‐diol) glucosides, itosides A–H ( 1 – 8 ), together with the new pyrocatechol (=benzene‐1,2‐diol) glycoside itoside I ( 9 ) were isolated from the bark and twigs of Itoa orientalis (Flacourtiaceae). In itosides B–D ( 2 – 4 ), the gentisyl alcohol moiety was esterified by 1‐hydroxy‐6‐oxocyclohex‐2‐ene‐1‐carboxylic acid, while itosides E–H ( 5 – 8 ) contained instead an additional 2‐hydroxybenzoic acid moiety. The compounds were accompanied by the known derivatives 4‐hydroxytremulacin ( 10 ), poliothyrsoside ( 11 ), poliothyrsin ( 12 ), homaloside D ( 13 ), tremulacin, and pyrocatechol β‐D ‐glucopyranoside. The structures of the new compounds were elucidated by spectral and chemical methods.  相似文献   

3.
Phytochemical investigation of Eupatorium chinense var. tozanense has resulted in the isolation of three new germacranolides, designated as eupatozansins A–C ( 1 – 3 ), along with five known compounds, (5S,6R,7R,8R)‐8‐angeloyloxy‐2‐oxoguaia‐1(10),3,11(13)‐trien‐12,6‐olide ( 4 ), costunolide ( 5 ), leptocarpin ( 6 ), 2α‐hydroxyeupatolide 8‐O‐angelate ( 7 ), and quercetin ( 8 ). The structures of the new compounds were identified by 1D and 2D NMR experiments, as well as high‐resolution mass spectrometry. The in vitro cytotoxic activities of compounds 1 – 8 were evaluated.  相似文献   

4.
Three new ent‐8,9‐secokaurane diterpenes, kongensins A–C ( 1 – 3 ), were isolated from the aerial parts of Croton kongensis, together with two known compounds, rabdoumbrosanin ( 4 ) and (7α,14β)‐7,14‐dihydroxy‐ent‐kaur‐16‐en‐15‐one ( 5 ). The structures of the new compounds were elucidated by HR‐MS as well as in‐depth 1D‐ and 2D‐NMR analyses. Compounds 1 – 3 showed an unusual oxygenation pattern, with an AcO or OH group at C(1), in combination with a Δ8(14) unsaturation ( 1 ) or an 8,14‐epoxide function ( 2, 3 ).  相似文献   

5.
Two novel sesquiterpene dimers, compounds 1 and 2 , were isolated from the rhizome of Ligularia virgaurea, together with the six known sesquiterpenoids 3 – 8 . Their structures were established by physico‐chemical and spectroscopic methods, especially by means of 1D‐ and 2D‐NMR as well as HR‐MS analyses. A mechanism based on a classical Diels–Alder cyclization is proposed for the formation of the dimer 1 from the precursors 8 and the quinone form of 6 (Scheme).  相似文献   

6.
Three new isomeric biisoflavonoids, dapholidins A–C ( 1 – 3 , resp.), have been isolated from the AcOEt‐soluble fraction of the MeOH‐soluble extract of the roots of Daphne oleoides, along with the known compounds daphwazirin ( 4 ), daphnetin 8‐Oβ‐D ‐glucopyranoside ( 5 ), daphnin ( 6 ), daphneticin 4″‐Oβ‐D ‐glucopyranoside ( 7 ), and 6,7‐dihydroxy‐3‐methoxy‐8‐[2‐oxo‐2H‐1‐benzopyran‐7‐(Oβ‐D ‐glucopyranosyl)‐8‐yl]‐2H‐1‐benzopyran‐2‐one ( 8 ). The structures of the new compounds were determined by spectroscopic analyses, including 1D‐ and 2D‐NMR.  相似文献   

7.
Halotolerant fungus Cladosporium cladosporioides OUCMDZ‐187 was isolated from the mangrove plant Rhizophora stylosa collected in Shankou, Guangxi Province of China. Three new fatty acid esters cladosporesters A–C ( 1 – 3 ) and 5 new fatty acids cladosporacids A–E ( 4 – 8 ) were isolated from the ethyl acetate extract of the fermentation broth of OUCMDZ‐187 in a hypersaline (10% salt) medium. Their structures were elucidated by UV, IR, MS, specific rotation, and 1D and 2D NMR data.  相似文献   

8.
Three new alkaloids, 2′‐Oβ‐D ‐glucopyranosyl‐11‐hydroxyvincoside lactam ( 1 ), 22‐O‐demethyl‐22‐Oβ‐D ‐glucopyranosylisocorynoxeine ( 2 ), and (4S)‐corynoxeine N‐oxide ( 3 ) were isolated from the leaves of Uncaria rhynchophylla, together with four known tetracyclic oxindole or indole alkaloids, isocorynoxeine N‐oxide ( 4 ), rhynchophylline N‐oxide ( 5 ), isorhynchophylline N‐oxide ( 6 ), and dihydrocorynantheine ( 7 ), and an indole alkaloid glycoside, strictosidine ( 8 ). The structures of 1 – 3 were elucidated by spectroscopic methods including UV, IR, ESI‐TOF‐MS, 1D‐ and 2D‐NMR, as well as CD experiments. The activity assay showed that 8 (IC50=8.3 μM ) exhibited potent inhibitory activity on lipopolysaccharide(LPS)‐induced nitrogen monoxide (NO) release in N9 microglia cells. However, only weak inhibitory activities were observed for 1 – 7 (IC50>100 μM for 1 – 6 or >30 μM for 7 ).  相似文献   

9.
Five new C19‐diterpenoid alkaloids, named hemsleyaconitines A–E ( 1 – 5 , resp.), were isolated from Aconitum hemsleyanum Pritz. By UV, IR, MS, 1D‐ and 2D‐NMR analyses, their structures were elucidated as 18‐dehydroxygeniculatine D ( 1 ), 6‐hydroxy‐14‐O‐veratroylneoline ( 2 ), 14‐O‐acetyl‐8‐ethoxysachaconitine ( 3 ), 18‐veratroylkaracoline ( 4 ) and 8‐O‐ethylaustroconitine B ( 5 ).  相似文献   

10.
Bioactivity‐guided isolation of the rare gorgonian Muricella sibogae (Nutting ) yielded the two new eunicellin diterpenes sibogin A and B ( 1 and 2 ), the three new 9,10‐secosteroids sibogol A–C ( 6 – 8 ), together with the three known eunicellin diterpenes 3 – 5 and the five known 9,10‐secosteroids 9 – 13 . Their structures were established by extensive spectral analysis (1D‐ and 2D‐NMR, IR, and MS). The cytotoxicity of the isolates 1 – 13 was evaluated in vitro against the selected tumor cell lines P388 and BEL‐7402. All the compounds showed only weak activity against P388 cell lines, with an inhibition rate ranging from 10 to 60% at a concentration of 50 μg/ml, whereas the were inactive against BEL‐7402 cell lines.  相似文献   

11.
Seven novel polyketides, namely, 1‐(xylarenone A)xylariate A ( 1 ), xylarioic acid B ( 2 ), xylariolide A ( 3 ), xylariolide B ( 4 ), xylariolide C ( 5 ), methyl xylariate C ( 6 ), and xylariolide D ( 7 ), together with the known one taiwapyrone ( 8 ), were isolated from the endophytic fungal strain Xylaria sp. NCY2 of Torreya jackii Chun . Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and on the basis of HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays of compounds 1 – 8 were carried out, which show moderate activities.  相似文献   

12.
Six new polyhydroxypregnane glycosides, namely cynotophyllosides A–F ( 1 – 6 ), together with five known steroids, were isolated from the roots of Cynanchum otophyllum. Their structures were elucidated by extensive spectroscopic methods (especially 2D‐NMR techniques) and acid‐catalyzed hydrolysis. Furthermore, high field 1D‐ and 2D‐NMR experiments were employed to elucidate the structure of 8 previously deduced only on the basis of LC/MS data.  相似文献   

13.
Seven new iridoid glucosides, 1 – 7 , two new phenyl glucosides, 8 and 9 , along with eight known compounds were isolated from the bark of Daphniphyllum angustifolium. Their structures were established by ESI‐MS and by 1D‐ and 2D‐NMR spectroscopic methods.  相似文献   

14.
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.  相似文献   

15.
Five new compounds were isolated from the roots of Ligularia dentata, including four bisabolane‐type sesquiterpenoids, 1 – 4 , as well a new eudesmane, 5 . The previously isolated 3α,6α,9‐tris(angeloyloxy)‐2α,4β‐dihydroxy‐7,11‐epoxybisabol‐10(15)‐en‐5‐one ( 6 ), when left as an oil in a refrigerator over nine months, gave rise to a mixture of two positional isomers, 7 and 8 . Their formation is rationalized by means of epoxide ring opening and shift of an angeloyl (Ang) group. The structures of compounds 1 – 5, 7 , and 8 were established by in‐depth spectroscopic (UV, CD, IR, 1D‐ and 2D‐NMR) as well as mass‐spectrometric methods.  相似文献   

16.
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.  相似文献   

17.
Four new phenolic glycosides, named rebouosides A–D ( 1 – 4 , resp.), along with three known ones 2‐(3,4‐dihydroxyphenyl)ethyl 2‐Oα‐L ‐rhamnopyranosyl‐β‐D ‐allopyranoside ( 5 ), 2‐(3,4‐dihydroxyphenyl)ethyl β‐D ‐allopyranoside ( 6 ), 2‐(3,4‐dihydroxyphenyl)ethyl β‐D ‐glucopyranoside ( 7 ), and a nucleoside, inosine ( 8 ), were isolated from Chinese liverwort Reboulia hemisphaerica. Their structures were elucidated by acidic hydrolysis and extensive spectroscopic methods, including 2D‐NMR techniques.  相似文献   

18.
Four new triterpene glycosides, named oleanazuroside 1 ( 1 ), oleanazuroside 2 ( 2 ), ursolazuroside 1 ( 3 ), and ursolazuroside 2 ( 4 ), together with the seven known compounds 5 – 11 , were isolated from the MeOH extract of the aerial parts of Anchusa azurea Miller var. azurea. Their structures were elucidated by means of spectroscopic evidence (UV, IR, MALDI‐MS, and 1D‐ and 2D‐NMR). The radical‐scavenging activities against 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) of the BuOH extract and of 8 and 10 were very strong (Table 5).  相似文献   

19.
A new family of 120° carbazole‐based dendritic donors D1 – D3 have been successfully designed and synthesized, from which a series of novel supramolecular carbazole‐based metallodendrimers with well‐defined shapes and sizes were successfully prepared by [2+2] and [3+3] coordination‐driven self‐assembly. The structures of newly designed rhomboidal and hexagonal metallodendrimers were characterized by multinuclear NMR (1H and 31P) spectroscopy, ESI‐TOF mass spectrometry, FTIR spectroscopy, and the PM6 semiempirical molecular orbital method. The fluorescence emission behavior of ligands D1 – D3 , rhomboidal metallodendrimers R1 – R3 , and hexagonal metallodendrimers H1 – H3 in mixtures of dichloromethane and n‐hexane with different n‐hexane fractions were investigated. The results indicated that D1 – D3 featured typical aggregation‐induced emission (AIE) properties. However, different from ligands D1 – D3 , metallodendrimers R1 – R3 and H1 – H3 presented interesting generation‐dependent AIE properties. Furthermore, evidence for the aggregation of these metallodendrimers was confirmed by a detailed investigation of dynamic light‐scattering, Tyndall effect, and SEM. This research not only provides a highly efficient strategy for constructing carbazole‐based dendrimers with well‐defined shapes and sizes, but also presents a new family of carbazole‐based dendritic ligands and rhomboidal and hexagonal metallodendrimers with interesting AIE properties.  相似文献   

20.
One new hydrolyzable tannin, 1‐O‐[(E)‐p‐coumaroyl]‐3‐O‐galloyl‐β‐D ‐glucopyranose ( 1 ), was isolated from the rhizome of Balanophora harlandii, together with 18 known phenolic compounds. Their structures were determined by detailed spectroscopic analysis. Of the known compounds, 3‐O‐caffeoyl‐D ‐glucopyranose ( 6 ) was obtained as a natural product for the first time, and compounds 2 – 6 and 8 – 19 were identified for the first time from this plant. The radical‐scavenging activity of the isolated compounds was tested by a DPPH assay.  相似文献   

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