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1.
Chemical investigation of the red herbal resin of Dracaena cochinchinensis resulted in the isolation of three new configurationally isomeric flavonoids: 6,4′‐dihydroxy‐7‐methoxy‐8‐methylflavane (=3,4‐dihydro‐2‐(4‐hydroxyphenyl)‐7‐methoxy‐8‐methyl‐2H‐[1]benzopyran‐6‐ol; 1 ), 5,4′‐dihydroxy‐7‐methoxy‐6‐methylflavane (=3,4‐dihydro‐2‐(4‐hydroxyphenyl)‐7‐methoxy‐6‐methyl‐2H‐[1]benzopyran‐5‐ol; 2 ), and 7,4′‐dihydroxy‐5‐ methoxyhomoisoflavane (=3,4‐dihydro‐3‐[(4‐hydroxyphenyl)methyl]‐5‐methoxy‐2H‐[1]benzopyran‐7‐ol; 3 ). Their structures were identified by means of detailed spectral analysis. In addition, thirteen known compounds were isolated from D. cochinchinensis: 7‐hydroxy‐4′‐methoxyflavane ( 4 ), 2,4,6‐trimethoxy‐4′‐hydroxydihydrochalcone ( 5 ), 2,4‐dimethoxy‐4′‐hydroxydihydrochalcone ( 6 ), 7,8‐(methylenedioxy)‐4′‐hydroxyhomoisoflavane ( 7 ), 4′,7‐dihydroxy‐8‐methylflavane ( 8 ), 2,6‐dimethoxy‐4,4′‐dihydroxydihydrochalcone ( 9 ), 2‐methoxy‐4,4′‐dihydroxydihydrochalcone ( 10 ), 7‐methoxy‐6,4′‐dihydroxyhomoisoflavane ( 11 ), 2‐methoxy‐4,4′‐dihydroxychalcone ( 12 ), 4′,7‐dihydroxyflavane ( 13 ), 7,4′‐dihydroxyhomoisoflavane ( 14 ), 7,4′‐dihydroxyhomoisoflavone ( 15 ), and 7,4′‐dihydroxyflavone ( 16 ). Compounds 7, 8, 9, 14 , and 15 have been isolated for the first time from this type of herbal source.  相似文献   

2.
Two new flavones, 8‐hydroxy‐7,3′,4′,5′‐tetramethoxyflavone and 8,4′‐dihydroxy‐7,3′,5′‐trimethoxyflavone, together with thirteen known compounds have been isolated from the stem bark of Muntingia calabura. The structures of two new compounds were determined through spectral analyses. Among the isolates, 8‐hydroxy‐7,3′,4′,5′‐tetramethoxyflavone, 8,4′‐dihydroxy‐7,3′,5′‐trimethoxyflavone, and 3‐hydroxy‐1‐(3,5‐dimethoxy‐4‐hydroxyphenyl)propan‐1‐one exhibited effective cytotoxicities (ED50 values = 3.56, 3.71, and 3.27 μg/mL, respectively) against the P‐388 cell line in vitro.  相似文献   

3.
The five new lignans designated 3′,4′‐de‐O‐methylenehinokinin ( 1 ), taiwaninolide ( 2 ), 8′‐hydroxysavinin ( 3 ), isoguamarol ( 4 ), and 4′‐O‐methylsalicifolin ( 5 ), as well as the new 4‐(3,4‐dimethoxybenzyl)dihydro‐3‐(4‐hydroxybenzyl)furan‐2(3H)‐one ( 6 ) were isolated from the roots of Taiwania cryptomerioides, besides the three known compounds hinokinin ( 8 ), savinin ( 9 ), and 3,4‐de‐O‐methylenehinokinin ( 7 ). The structures of the new constituents were elucidated through chemical and spectral studies. A compound previously isolated from the heartwood of Chamaecyparis obtusa var. formosana was assigned structure 1 ; however, this structure has now been revised to be 3,4‐de‐O‐methylenehinokinin ( 7 ).  相似文献   

4.
Pakistolides A and B, novel dimeric β‐(glucosyloxy)benzoates were isolated from Berchemia pakistanica and assigned structures 1 and 2 on the basis of extensive NMR studies. In addition, the known compounds 7,5′‐dimethoxy‐3,5,2′‐trihydroxyflavone (=3,5‐dihydroxy‐2‐(2‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one), 4′,5‐dihydroxy‐3,6,7‐trimethoxyflavone (=5‐hydroxy‐2‐(4‐hydroxyphenyl)‐3,6,7‐trimethoxy‐4H‐1‐benzopyran‐4‐one), 5,6‐dihydroxy‐4,7‐dimethoxy‐2‐methylanthracene‐9,10‐dione, and 1,3,4‐trihydroxy‐6,7,8‐trimethoxy‐2‐methylanthracene‐9,10‐dione were reported for the first time from the genus Berchemia. Both 1 and 2 showed significant α‐glucosidase and lipoxygenase inhibitory activities, while 2 also showed antioxidant potential.  相似文献   

5.
Three new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1 ), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2 ), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3 ) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.  相似文献   

6.
One new ceramide (=long‐chain base linked to a fatty acid via an amide bond), tanacetamide D ( 1 ), was isolated from Tanacetum artemisioides. Besides this, the two known constituents 5‐demethylnobiletin ( 2 ) and 5‐hydroxy‐3,6,7,8,3′,4′‐hexamethoxyflavone ( 3 ) were isolated for the first time from this species. The structure elucidation of the isolated compounds were based primarily on 2D‐NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple‐quantum coherence (HMQC), heteronuclear multiple‐bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY) experiments.  相似文献   

7.
Previous investigations of the aerial parts of the Australian plant Eremophila microtheca and Syzygium tierneyanum resulted in the isolation of the antimicrobial flavonoid jaceosidin ( 4 ) and 2′,6′‐dihydroxy‐4′‐methoxy‐3′,5′‐dimethyl chalcone ( 7 ), respectively. In this current study, compounds 4 and 7 were derivatized by acetylation, pivaloylation, and methylation reactions. The final products, 5,7,4′‐triacetoxy jaceosidin ( 10 ), 5,7,4′‐tripivaloyloxy jaceosidin ( 11 ), 5,7,4′‐trimethoxy jaceosidin ( 12 ), 2′,6′‐diacetoxy‐4′‐methoxy‐3′,5′‐dimethyl chalcone ( 13 ), 2′‐hydroxy‐4′‐methoxy‐6′‐pivaloyloxy‐3′,5′‐dimethyl chalcone ( 14 ), and 2′‐hydroxy‐4′,6′‐dimethoxy‐3′,5′‐dimethyl chalcone ( 15 ) were all fully characterized by NMR and MS. Derivatives 10 and 13 have been previously reported but were only partially characterized. This is the first reported synthesis of 11 and 14 . The natural products and their derivatives were evaluated for their antibacterial and antifungal properties, and the natural product, jaceosidin ( 4 ) and the acetylated derivative, 5,7,4′‐triacetoxy jaceosidin ( 10 ), showed modest antibacterial activity (32–128 µg/ml) against Staphylococcus aureus strains. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
From the fruit coats of the medicinal plant Madhuca latifolia were isolated three new compounds, the triterpenoid madhucic acid (=3β‐(octanoyloxy)‐11‐oxoolean‐12‐en‐28‐oic acid; 1 ), the untypical isoflavone madhushazone (=9‐methoxy‐7‐(2,3,6‐trimethoxyphenyl)‐[1,3]dioxolo[4,5‐g][1]benzopyran‐8(8H)‐one; 2 ), and a bis(isoflavone) named madhusalmone (=5,14‐dimethoxy‐3,12‐bis(3,4,5‐trimethoxyphenyl)‐1,6,8,10,15,17‐hexaoxanaphtho[2′,3′: 6,7]cyclodeca[1,2‐b]naphthalene‐4,13(4H,13H)‐dione; 3 ), as well as eight known constituents, and their structures were elucidated by spectral analysis, including 2D‐NMR techniques.  相似文献   

9.
Seven phenolic compounds, including one new compound trans‐3,4,3′,5′‐tetrahydroxy‐4′‐methylstilbene 4‐O‐β‐D‐xylopyranosyl‐(1→6)‐β‐D‐glucopyranoside ( 1 ), together with six known compounds (+)‐hinokiol ( 2 ), 6‐hydroxy‐5,7‐dimethoxycoumarin ( 3 ), caffeic acid ( 4 ), vanillic acid ( 5 ), 4‐hydroxy‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 6 ) and 4‐allyl‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 7 ), were isolated from the root bark of Elsholtzia bodinieri Van't. Their structures were determined on the basis of spectroscopic and chemical evidence.  相似文献   

10.
A novel dihydroisocoumarin, 3,4‐dihydro‐6,8‐dihydroxy‐3‐(2′‐acetyl‐3′‐hydroxy‐5′‐methoxy)methyl‐1H‐[2]benzopyran‐1‐one, was isolated from the chloroform extract of the sap of the traditional herb Aloe vera. Its structure was determined by high‐resolution negative fast atom bombardment mass spectrometry (MS), 2D NMR spectroscopy and x‐ray crystallography. The molecular structure was elucidated by 2D NMR analysis. The complete assignment of the 1H and 13C NMR spectra of this compound was performed by using 1H detected one‐bond heteronuclear multiple quantum correlation (HMQC) and long‐range (two and three bonds) heteronuclear multiple quantum bond correlation (HMBC) experiments. Detailed analyses of the one‐ and two‐dimensional NMR techniques are presented in additional to the spectral properties (MS, IR and UV). Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

11.
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   

12.
Fourteen polyphenolic compounds were isolated from the 60% aqueous acetone extract of Formosan Euphorbia tirucalli L. (Euphorbiaceae). Two compounds, 5‐desgalloylstarchyurin and 3,3′,4‐tri‐O‐methyl‐4′‐O‐rutinosyl ellagic acid, were deduced by concerted application of 1D and 2D NMR methods, and reassigned their NMR data.  相似文献   

13.
Two new one‐dimensional CuII coordination polymers (CPs) containing the C2h‐symmetric terphenyl‐based dicarboxylate linker 1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylate (3,3′‐TPDC), namely catena‐poly[[bis(dimethylamine‐κN)copper(II)]‐μ‐1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylato‐κ4O,O′:O′′:O′′′] monohydrate], {[Cu(C20H12O4)(C2H7N)2]·H2O}n, (I), and catena‐poly[[aquabis(dimethylamine‐κN)copper(II)]‐μ‐1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylato‐κ2O3:O3′] monohydrate], {[Cu(C20H12O4)(C2H7N)2(H2O)]·H2O}n, (II), were both obtained from two different methods of preparation: one reaction was performed in the presence of 1,4‐diazabicyclo[2.2.2]octane (DABCO) as a potential pillar ligand and the other was carried out in the absence of the DABCO pillar. Both reactions afforded crystals of different colours, i.e. violet plates for (I) and blue needles for (II), both of which were analysed by X‐ray crystallography. The 3,3′‐TPDC bridging ligands coordinate the CuII ions in asymmetric chelating modes in (I) and in monodenate binding modes in (II), forming one‐dimensional chains in each case. Both coordination polymers contain two coordinated dimethylamine ligands in mutually trans positions, and there is an additional aqua ligand in (II). The solvent water molecules are involved in hydrogen bonds between the one‐dimensional coordination polymer chains, forming a two‐dimensional network in (I) and a three‐dimensional network in (II).  相似文献   

14.
An efficient route to 2′,3′‐dihydro‐2′‐thioxospiro[indole‐3,6′‐[1,3]thiazin]‐2(1H)‐one derivatives is described. It involves the reaction of isatine, 1‐phenyl‐2‐(1,1,1‐triphenyl‐λ5‐phosphanylidene)ethan‐1‐one, and different amines in the presence of CS2 in dry MeOH at reflux (Scheme 1). The alkyl carbamodithioate, which results from the addition of the amine to CS2, is added to the α,β‐unsaturated ketone, resulting from the reaction between 1‐phenyl‐2‐(1,1,1‐triphenyl‐λ5‐phosphanylidene)ethan‐1‐one and isatine, to produce the 3′‐alkyl‐2′,3′‐dihydro‐4′‐phenyl‐2′‐thioxospiro[indole‐3,6′‐[1,3]thiazin]‐2(1H)‐one derivatives in excellent yields (Scheme 2). Their structures were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses.  相似文献   

15.
Two new flavone glycosides, 3′‐hydroxy‐5,7‐dimethoxyflavone 4′‐O‐β‐D‐apiofuranoside ( 1 ), and 5,7‐dimethoxyflavone 4′‐O‐[β‐D‐apiofuranosyl(1→5)‐ β‐D‐glucopyranoside] ( 2 ) along with four known compounds, 4′‐hydroxy‐5,7‐dimethoxyflavone ( 3 ), 2,6‐dimethoxy‐1,4‐benzoquinone ( 4 ), lupeol ( 5 ) and betulin ( 6 ) were isolated from the stem and roots of Strobilanthes formosanus. Their structures were elucidated on the basis of their spectroscopic evidence.  相似文献   

16.
Two coordination polymers, {[Zn2(L)(bpy)] · 2H2O}n ( 1 ) and [Zn2(L)(bpe)]n ( 2 ) [H4L = terphenyl‐2,2′,4,4′‐tetracarboxylic acid, bpy = 4,4′‐bipyridine, and bpe = 1,2‐bis(4‐pyridyl)ethane], were hydrothermally synthesized under similar conditions and characterized by elemental analysis, IR spectroscopy, TGA, and single‐crystal X‐ray diffraction analysis. Compound 1 has a 3D framework containing Zn–O–C–O–Zn 1D chains. Compound 2 exhibits a 3D framework, which features tubular channels. The channels are occupied by bpe molecules. The differences in the structures demonstrate that the auxiliary dipyridyl‐containing ligand has a significant effect on the construction of the final framework. Additionally, the fluorescent properties of the two compounds were also studied in the solid state at room temperature.  相似文献   

17.
A new trimer from the reaction of ageratochromene [1] (6,7‐dimethoxy‐2,2‐dimethyl‐1‐benzopyran) with anhydrous aluminum chloride was shown to be 3,4‐dihydro‐6,7‐dimethoxy‐2,2‐dimethyl‐3‐(6′,7′‐dimethoxy‐2′,2′‐dimethyl‐2H‐1‐benzopyran‐4′‐yl)‐4‐(3′,4′‐dihydro‐6′, 7′‐dimethoxy‐2′,2′‐dimethyl‐2H‐1‐benzopyran‐3′‐yl)‐ 2H‐1‐benzopyran. Its structure was confirmed by NMR (1H, 13C, DEPT‐135. COSY, HMBC, HSQC, TOCSY and NOESY), IR, mass spectra and elemental analysis. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

18.
Four new transitional metal supramolecular architectures, [Zn(cca)(2,2′‐bpy)]n · n(2,2′‐bpy) ( 1 ), [Cu(cca)(2,2′‐bpy)]n ( 2 ), [Zn(bpdc)(2,2′‐bpy)(H2O)]n · 0.5nDMF · 1.5nH2O ( 3 ), and [Co(bpdc)(2,2′‐bpy)(H2O)]n · nH2O ( 4 ) (H2cca = p‐carboxycinnamic acid; H2bpdc = 4,4′‐biphenyldicarboxylic acid; 2,2′‐bpy = 2,2′‐bipyridine) were synthesized by hydrothermal reactions and characterized by single crystal X‐ray diffraction, elemental analyses, and IR spectroscopy. Although the metal ions in these four compounds are bridged by linear dicarboxylic acid into 1D infinite chains, there are different π–π stacking interactions between the chains, which results in the formation of different 3D supramolecular networks. Compound 1 is of a 3D open‐framework with free 2,2′‐bpy molecules in the channels, whereas compound 2 is of a complicated 3D supramolecular network. Compounds 3 and 4 are isostructural. Both compounds have open‐frameworks.  相似文献   

19.
Two new coordination polymers, {[Cd2(btc)(2,2′‐bpy)2] · H2O}n ( 1 ) and [Zn2(btc)(2,2′‐bpy)(H2O)]n ( 2 ) (H4btc = biphenyl‐2,2′,4,4′‐tetracarboxylic acid, 2,2′‐bpy = 2,2′‐bipyridine), were synthesized hydrothermally under similar conditions and characterized by elemental analysis, IR spectra, TGA, and single‐crystal X‐ray diffraction analysis. In complexes 1 and 2 , the (btc)4– ligand acts as connectors to link metal ions to give a 2D bilayer network of 1 and a 3D metal‐organic framework of 2 , respectively. The differences in the structures are induced by diverging coordination modes of the (btc)4– ligand, which can be attributed to the difference metal ions in sizes. The results indicate that metal ions have significant effects on the formation and structures of the final complexes. Additionally, the fluorescent properties of the two complexes were also studied in the solid state at room temperature.  相似文献   

20.
Two new prenylated flavanones, ficubee A and ficubee B, respectively, as 7,8‐(2,2‐dimethylpyrano)‐6‐prenyl‐5,3′,4′‐trihydroxyflavone and 6,7‐(2,2‐dimethylpyrano)‐8‐prenyl‐5,3′,4′‐trihydroxyflavone were isolated from the roots of Ficus beecheyana together with twelve known compounds: β‐sitosterol, 5‐stigmasten‐3β,7α‐diol, 5‐stigmasten‐3β,7β‐diol, 3β‐hydroxystigmast‐5‐en‐7‐one, 4‐hydroxybenzaldehyde, 4‐hydroxy‐3‐methoxybenzaldehyde, 1‐(4‐hydroxyphenyl)‐ethanone, 4‐hydroxy‐3‐methoxybenzoic acid, 4‐hydroxy‐cinnamic acid, seseline, xanthyletin, and psoralene. The structures of these secondary metabolites were determined by spectroscopic means and in comparison with published data.  相似文献   

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