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1.
Asprellols A–C ( 1 – 3 , resp.), three new 24‐nortriterpenoids, were isolated from the CHCl3‐soluble fraction of 95% EtOH extract of the roots of Ilex asprella, together with a known nortriterpenoid. The structures of the new compounds were elucidated as 2,6β,20β‐trihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐norursa‐1,4‐dien‐28,13β‐olide ( 1 ), 2,6β‐dihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐norursa‐1,4,20(30)‐trien‐28,13β‐olide ( 2 ), and 2,6β‐dihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐noroleana‐1,4‐dien‐28,13β‐olide ( 3 ) on the basis of spectroscopic analyses.  相似文献   

2.
Phytochemical investigation on the leaves of Ilex hainanensis Merr . led to the isolation of four new ursane‐ and oleanane‐based triterpenoids, ilexhainanins A–D ( 1 – 4 ), as well as two known compounds, 2α,3β,19α‐trihydroxyurs‐12‐ene‐23,28‐dioic acid and 2α,3β,19α‐trihydroxyolean‐12‐ene‐23,28‐dioic acid. Their structures were elucidated on the basis of chemical and spectroscopic evidence, and by comparison with literature data.  相似文献   

3.
Chemical investigation of the MeOH extract of the leaves of Gynura procumbens (Lour .) Merr . afforded one new sesquiterpenoid, muurol‐4‐ene‐1β,3β,10β‐triol ( 1 ), and two sesquiterpene glycosides, muurol‐4‐ene‐1β,3β,10β‐triol 3‐Oβ‐D ‐glucopyranoside ( 2 ) and muurol‐4‐ene‐1β,3β,15‐triol 3‐Oβ‐D ‐glucopyranoside ( 3 ), together with three known sesquiterpenoids. Their structures were elucidated on the basis of spectroscopic analyses and chemical methods.  相似文献   

4.
以5-雄烯二醇为原料,用微生物转化的方法合成了两个重要的神经甾体5-雄烯-3β, 7α, 17β-三醇和5-雄烯-3β, 7β, 17β-三醇。所用菌种总枝毛霉为我们自己筛选,并首次应用于5-雄烯-3β, 7α, 17β-三醇和5-雄烯-3β, 7β, 17β-三醇的合成中。  相似文献   

5.
汤灿  曾清如  周细红  杨成建 《中国化学》2005,23(12):1677-1682
The effectiveness of the solubilization and photodegradation of β-cyclodextrin (β-CD) and hydroxypropyl-β- cyclodextrin (HPCD) on two hydrophobic organic compounds (HOC) of methyl parathion and pentachlorophenol was investigated. The results indicate that the solubilization or photodegradation of two HOC were influenced by complexing with β-CD or HPCD. The solubility of pentachlorophenol (PCP) was increased linearly with β-CD concentration. The solubility of methyl parathion (MPT) was increased with the increase of β-CD concentration initially, however, as the β-CD concentration was enhanced above 3 g/L, the solubility was decreased with increase of β-CD concentration. The solubilities of two HOC were increased linearly with the increase of HPCD concentration. Although the photodegradation of MPT was improved, the photodegradation of PCP was restrained by complexation of HOC with β-CD or HPCD. In a word, the effectiveness of photodegradation or solubilization of HPCD was more significant than that of β-CD. One potential application of such a method was the in situ remediation of hydrophobic organic pollutants in contaminated soil and groundwater or industrial waste streams.  相似文献   

6.
A new megastigmane palmitate, 9‐oxomegastigm‐5(13)‐ene‐2β‐palmitate ( 1 ), and a new oleanane triterpenoid, (3β)‐3,23,28‐trihydroxyolean‐12‐en‐11‐one ( 2 ), together with three known oleanane‐type triterpenoids, β‐amyrin ( 3 ), erythrodiol ( 4 ), and (3β)‐olean‐12‐ene‐3,23,28‐triol ( 5 ), were isolated from the aerial parts of Aster yomena (Asteraceae). Their structures were identified based on 1D‐ and 2D‐NMR analysis, including 1H,1H‐COSY, HSQC, HMBC, and NOESY techniques.  相似文献   

7.
Binary and ternary systems composed of dapsone, sulfobutylether‐β‐cyclodextrin (SBE‐β‐CD), β‐CD and egg phosphatidylcholine (EPC) were evaluated using 1D ROESY, saturation transfer difference NMR and diffusion experiments (DOSY) revealing the binary complexes Dap/β‐CD (Ka 1396 l mol?1), Dap/SBE‐β‐CD (Ka 246 l mol?1), Dap/EPC (Ka 84 l mol?1) and the ternary complex Dap/β‐CD/EPC (Ka 18 l mol?1) in which dapsone is more soluble. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

8.
The triterpene ester (3β)‐olean‐18‐en‐3‐yl stearate ( 1 ), together with (3β)‐urs‐12‐en‐3‐yl stearate ( 2 ), and (3β)‐lup‐20(29)‐en‐3‐yl stearate ( 3 ) were isolated from leaves of Maytenus salicifolia Reissek (Celastraceae). The structure of 1 , a new compound, including its configuration, was established by 1H, 13C, and DEPT‐135 NMR data, including 2D experiments (HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/MS).  相似文献   

9.
β‐Diimine zinc dichloride complexes [CH2{C(Me)NAr}2]ZnCl2 [Ar = Mes ( 1 ), Dipp ( 2 )] were obtained from the reactions of ZnCl2 with the corresponding β‐iminoamines [ArN(H)C(Me)CHC(Me)NAr]. Complexes 1 and 2 were characterized by multinuclear NMR (1H, 13C) and IR spectroscopy, elemental analyses as well as by single‐crystal X‐ray diffraction. The energy differences between the enamine‐imine tautomers of the β‐iminoamines were quantified by quantum chemical calculations.  相似文献   

10.
李颜  吴弢  程志红  王峥涛 《中国化学》2006,24(4):577-579
A new triterpene glycoside, pomolic acid 3-O-6″-methyl-β-D-glucuronopyranosyl-(1→3)-α-L-arabino- pyranoside, and a new flavonol glycoside, quercetin 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranoside together with three known triterpene saponins and two flavonol glycosides, were isolated from the leaves of Ilex cornuta. Their structures were established on the basis of spectroscopic analysis.  相似文献   

11.
Two novel sesquiterpene polyol esters with a dihydro‐β‐agarofuran (=(3R,5aS,9R,9aS)‐octahydro‐2,2,5a,9‐tetramethyl‐2H‐3,9a‐methano‐1‐benzoxepin) skeleton, (1α,2α,4β,8α,9α)‐1,2,8,12‐tetrakis(acetyloxy)‐9‐(furoyloxy)‐4‐hydroxydihydro‐β‐agarofuran ( 1 ) and (1α,2α,6β,8α,9α)‐1,2,6,8,12‐pentakis(acetyloxy)‐9‐(benzoyloxy)dihydro‐β‐agarofuran ( 2 ), and the three known compounds (1α,2α,4β,6β,8α,9β)‐1,2,6‐tris(acetyloxy)‐9‐(benzoyloxy)‐4‐hydroxy‐8,12‐bis(isobutyryloxy)dihydro‐β‐agarofuran ( 3 ), (1α, 2α,4β,6β,8α,9β)‐1,2,6,8‐tetrakis(acetyloxy)‐9‐(furoyloxy)‐4‐hydroxy‐12‐isobutyryloxy)dihydro‐β‐agarofuran ( 4 ), and (1α,2α,4β,6β,8α,9β)‐1,2,6‐tris(acetyloxy)‐9‐(benzoyloxy)‐4‐hydroxy‐8‐(isobutyryloxy)‐12‐[(2‐methylbutanoyl)oxy]dihydro‐β‐agarofuran ( 5 ) were isolated from the root bark of Celastrus angulatus. Their chemical structures were elucidated by analyses of their MS and NMR data.  相似文献   

12.
Sixteen compounds, (+)-ushinsunine-β-N-oxide ( 1 ), cleistopholine ( 2 ), liriodenine ( 3 ), (-)-anonaine ( 4 ), (+)-nornuciferine ( 5 ), (+)-N-acetylnornuciferine ( 6 ), (-)-ushinsunine ( 7 ), (-)-norushinsunine ( 8 ), (-)-asimilobine ( 9 ), (+)-reticuline ( 10 ), N-trans-feruloyltyramine ( 11 ), β-sitosterol (12) and stigmasterol ( 13 ), lyscamine ( 14 ), (-)-anaxagoreine ( 15 ) and trans-cinnamic acid ( 16 ) were isolated from the methanolic extract of the Cananga odorata. Among them, 1 is a new stereoisomer of ushinsunine-β-N-oxide. The structures of these compounds were established by means of spectral experiments.  相似文献   

13.
Thymosin β4 (Tβ4), its sulfoxide, and thymosin β10 (Tβ10) were detected in human saliva and identified by different strategies based on RP HPLC coupled to electrospray multidimensional IT MS. Tβ4 was almost always detected in whole saliva, its sulfoxide sporadically, Tβ10 rarely. Tβ4 was undetectable in parotid saliva and less concentrated in submandibular/sublingual saliva than in whole saliva. Analysis of gingival crevicular fluid revealed high relative amounts of Tβ4, Tβ4 sulfoxide, and Tβ10 in all the samples. Tβ4 mean concentration was 200 times higher in crevicular fluid (20 μmol/L, N = 9) than in whole saliva (0.1 μmol/L, N = 9). Crevicular fluid concentration of Tβ4 (ca. 5% represented by its sulfoxide) and β10 significantly correlated (r = 0.856; N = 9), and their ratio was about 5. A significant correlation was also observed between Tβ4 concentrations in whole saliva and gingival crevicular fluid (r = 0.738; N = 9). Immunohistochemical analysis of the major salivary glands showed that immunoreactivity for Tβ4 is restricted to ductal cells, with minor degree of focal positivity in some acinar cells. On the whole, results indicate that gingival sulcus is a main, although not the sole, source for oral Tβ4 and Tβ10.  相似文献   

14.
The selectivities of different β‐nucleating agents might be quite different from each other, which is important in determining the crystallization and properties of the obtained β‐isotactic polypropylene (β‐iPP). However, the relationship between molecular structure and dynamic crystallization behavior of β‐iPP nucleated by dual‐selective β‐nucleating agent (DS‐β‐NA) is still not clear. In this study, the dynamic crystallization and melting behavior of two β‐iPP with nearly same average isotacticity but different stereo‐defect distribution, nucleated by a DS‐β‐NA (N,N′‐dicyclohexyl‐2,6‐naphthalenedicarboxamide; trade name TMB‐5), were studied by differential scanning calorimetry, wide‐angle X‐ray diffraction, and scanning electronic microscopy. The results indicated that in the presence of TMB‐5, the dynamic crystallization and melting behavior of the samples are quite different because the joint effects of the dual selectivity of TMB‐5 and stereo‐defect distribution of the iPP under different cooling rates. Two important roles were observed: (i) slow cooling rate favors the formation of high β‐fraction; and (ii) high crystallization temperature favors the crystallization of α‐phase accelerated by TMB‐5. Generally, the dual selectivity of the DS‐β‐NA, the stereo‐defect distribution of iPP, and the cooling rate were important factors in determining the formation of β‐crystal. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
Chemical investigation of the aerial parts of Senecio polypodioides lead to the isolation of the new eudesmanoid 1β‐angeloyloxyeudesm‐7‐ene‐4β,9α‐diol ( 1 ) and the known dirhamnosyl flavonoid lespidin ( 3 ), while from roots, the known 7β‐angeloyloxy‐1‐methylene‐8α‐pyrrolizidine ( 5 ) and sarracine N‐oxide ( 6 ), as well as the new neosarracine N‐oxide ( 8 ), were obtained. The structure of 1 and 8 was elucidated by spectral means. Complete assignments of the 1H NMR data for 5 , 6 , sarracine ( 7 ), and 8 were made using one‐dimensional and two‐dimensional NMR experiments and by application of the iterative full spin analysis of the PERCH NMR software. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

16.
Two new steroidal alkaloids, neoverapatuline ( 1 ) and (1β,3α,5β)‐1,3‐dihydroxyjervanin‐12‐en‐11‐one ( 2 ), together with the four known compounds, veratramine ( 3 ), rubijervine ( 4 ), veratrosine ( 5 ), and veratroylzygadenine ( 6 ), were isolated from the roots and rhizomes of Veratrum nigrum L. Their structures were established through combined analyses of physicochemical properties and spectroscopic evidence. All compounds 1 – 6 were tested for their cytotoxicities in vitro against the human glioma cell line SF188.  相似文献   

17.
Two new lycopodine alkaloids, (12β)‐12‐hydroxyhuperzine G ( 1 ) and (5β,6β,15α)‐15‐methyllycopodane‐5,6‐diol ( 2 ), were isolated from the whole plants of Huperzia serrata, together with six known compounds, huperzines A, B, and G, phlegmariurine B, (8β)‐8‐hydroxyphlegmariurine B, and lycoposerramine D. Their structures were elucidated on the basis of spectroscopic analysis, including HR‐ESI‐MS, 1H‐ and 13C‐NMR, DEPT, 1H,1H‐COSY, HSQC, HMBC, and NOESY data.  相似文献   

18.
Three novel bis(β‐cyclodextrin (CD))s with flexible glycol linkers, i.e., ethylene glycol‐bridged bis(6‐hydroxy‐6‐deoxy‐β‐CD) ( 2 ), diethylene glycol‐bridged bis(6‐hydroxy‐6‐deoxy‐β‐CD) ( 3 ), and triethylene glycol‐bridged bis(6‐hydroxy‐6‐deoxy‐β‐CD) ( 4 ) have been synthesized by the reaction of mono[6‐O‐(p‐toluenesulfonyl)]‐β‐CD with corresponding materials. The inclusion complexation behaviors of these compounds 2 – 4 with organic dyes; that is, acridine red (=N‐[(3Z)‐6‐(methylamino)‐3H‐xanthen‐3‐ylidene]methanaminium chloride; AR), neutral red (=N8,N8,3‐trimethylphenazine‐2,8‐diamine hydrochloride; NR), ammonium 8‐anilinonaphthalene‐1‐sulfonate (ANS), sodium 6‐(p‐toluidinyl)‐naphthalene‐2‐sulfonate (TNS), rhodamine B (RhB) and brilliant green (=N‐(4‐{[4‐(diethylamino)cyclohexa‐2,5‐dien‐1‐yl](phenyl)methyl}cyclohex‐2‐en‐1‐ylidene)‐N‐ethyl‐ethanaminium hydrogen sulfate; BG), have been investigated at 25° in phosphate buffer (pH 7.20) by ultraviolet, fluorescence, and 2D‐NMR spectroscopy. The results indicate that the two linked CD units may cooperatively bind a guest, and the molecular binding ability toward dye guests, especially bent ANS, T‐shaped RhB, and triangular BG, can be extended. This cooperative binding mode is confirmed by Job's experiments and 2D‐NMR investigations. Furthermore, the complex stability depends greatly on the linker length of these glycol‐bridged bis(β‐CD)s and the size and shape of guest. The higher binding ability and selectivity of dye molecules by bis(β‐CD)s 2 – 4 are discussed from the viewpoint of size/shape‐fit concept and multiple recognition mechanism.  相似文献   

19.
Catalytic base‐induced decarboxylation of polyunsaturated α‐cyano‐β‐methyl acids derived from malonic acid led to the corresponding nitriles 3 (Schemes 2 and 3), 6 (Scheme 5), and 9 (Scheme 6). This decarboxylation occurred with previous deconjugation of the α,β‐alkene moiety of the α‐cyano‐β‐methyl acid, leading to an α‐cyano‐β‐methylene propanoic acid which was easily decarboxylated (see Scheme 2). β‐Methylene intermediates, in some cases, could be isolated; mechanistic pathways are proposed. The nitriles 3, 6 , and 9 were reduced to the sesquiterpene aldehydes 4 (β‐end group), 7 (φ‐end group), and 10 (ψ‐end group), respectively.  相似文献   

20.
The chemical constituents of the roots of Zizyphus jujuba Mill. var. spinosa were investigated with a combination of Sephadex LH-20 column, centrifugal partition chromatography and RP-18 low pressure liquid chromatography. We isolated seven flavonoids-quercetin ( 1 ), (+)-dihydroquercetin ( 2 ), (+)-dihydrokaempferol ( 7 ), quercetin-3-0-β-glucoside ( 8 ), 2-hydroxynaringenin ( 11 ), rutin ( 12 ), and quercetin 3-0-(2G-β-D-xylopyranosylrutinoside) ( 13 ); four catechins-(-)-gallocatechin ( 3 ), (-)-epigallocatechin ( 4 ), (-)-catechin ( 5 ), and (-)-epicatechin ( 6 ); and two phenolic carboxylic acids-p-hydroxybenzoic acid ( 9 ) and protocatechuic acid ( 10 ) from the water soluble fraction of the ethanolic extract NMR date of 13 were assigned by 2D NMR techniques.  相似文献   

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