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1.
In present literature search, some cyano-containing compounds, which are very rare in plants, from the traditional anticancer herb Tiankuizi were reported. To find more cyano-containing compounds in the important plant Semiaquilegia adoxoides (DC) Makino (Chinese name Tiankuizi), the isolation of the chemical constituents was investigated for advancing the research. Two new compounds, a new alkaloid, 1,2,3,4-tetrahydro-6-hydroxy-1[(3,4-dihydroxyphenyl)methyl]-7-methoxy-2,2-dimethyl-isoquinolinium, named Semiaquilegine A (1), and a new ester, 3-(4'-hydroxyphenyl)-2-propenoic acid (4"-carboxyl)-phenyl ester (2), and four cyano-containing compounds, (Z)-6a-(β-D-glucosyloxy)-4a,5a-dihydroxy-2-cyclohexene-△^1,a-acetonitrile (3), (L0-6α-(β-D-glucosyloxy)-4α-hydroxy-2-cyclohexene-△^1,α-acetonitrile (4), lithospermoside (5), ehretioside B (6), as well as eleven known compounds, were isolated from the roots of Semiaquilegia adoxoides. The structures of new compounds 1 and 2 were elucidated mainly by 1D/2D-NMR techniques. Very unusual cyano-containing compounds 3 and 4 were first isolated from Ranunculaceae family. Hitherto, there were six cyano-containing compounds found in the herb.  相似文献   

2.
S.-L. Wu  F.-C. Lu 《Liquid crystals》2013,40(11):1517-1523
Three homologous series of chiral swallow-tailed compounds, alkyl (S)-2-{6-[4-(4′-alkoxyphenyl)benzoyloxy]-2-naphthyl}propionates, (S)HNP(p,n,q) derived from (S)-2-(6-hydroxy-2-naphthyl)propionic acid in conjugation with a variety of swallow-tailed groups, attached to the external side of the chiral centre, have been synthesized and their mesomorphic and electro-optical properties studied. Both (S)HNP(p,1,2) and (S)HNP(p,1,3) exhibited an enantiotropic antiferroelectric SmC*A phase. This implys that the swallow-tailed groups in the molecules favour zigzag pairing of the molecules in the smectic phase. The maximum P S values of compounds (S)HNP(p,1,2) in the antiferroelectric phase were measured in the range 21–30 nC cm-2; those of compounds (S)HNP(p,1,3) were in the range 15–23 nC cm-2, indicating that these chiral compounds possess low polarity. The electro-optical response of the compounds in the antiferroelectric SmC*A phase displayed thresholdless V-shaped switching.  相似文献   

3.
A new procedure for the cyclization of 2-indolecarbohydrazones (5) to 1,2,3,4-tetrahydro-4-oxo-5H-pyridazino[4,5-b]indoles (6) and for the cyclization of 3-indolecarbohydrazones (7) to 1-oxo-1,2,3,4-tetrahydro-5H-pyridazino[4,5-b]indoles (8 and 9) is described. The hydrazones (5 or 7) were treated with an acyl halide (acetyl or benzoyl chlorides) and triethylamine in ethyl acetate of chloroform as solvents to give the compounds 6 (20–70%) from the compounds 5 , and the compounds 8 (20–60%) from the compounds 7 . Through refluxing with ethanol-hydrochloric acid the compounds 8a-8f selectively separate the acetyl group on N5 to give the respective compounds, 9a-9f. The ir and 1H-nmr spectra of all the compounds 5, 6, 7, 8 and 9 and the uv, mass and 13C-nmr spectra of the compounds 7h, 7i, 8h and 8i are discussed.  相似文献   

4.
李曦  刘义 《中国化学》2002,20(9):829-833
The action of β-(N-selenomorpholine) ethyl phenyl ketone hydrochloride and 4-(N-selenomorpholine)-2-butanone hydro-chloride on Escherichia coli and Staphylococcus aureus was studied by microcalorimetry,Differences in their capacities to affect the metabolism of this bacterium were observed.The kinetics shows that the selenomorpholine compounds had action on the metabolism process of Escherichia coli and Staphylococcus aureus.The rate constant (k) of the studied bacterium in the presence of the drugs are concentration-dependant.The growth rate constants decrease with an increase in the mass of the selenomorpholine compounds ,but their relationship is different.As deduced from the rate constant(k) of the studied bacterium(in log phase )and the half inhibitory concentration (IC50),the experimental results reveal that the studied selenomorpholine compounds all have good antibiotic activity and better antibacterial activity on Staphylcoccus aureus than on Escherichia coli.  相似文献   

5.
A new flavonoid, dhasingreoside (1) and seven known compounds, quercetin 3-O-β-d-galacturonopyranoside (2), quercetin 3-O-β-d-galactopyranoside (3), quercetin 3-O-β-d-glucuronopyranoside (4), quercetin 3-O-α-l-rhamnopyranoside (5), (–)-epicatechin (6), salicylic acid (7) and gaultherin (8), have been isolated from the shade-dried stems and leaves of Gaultheria fragrantissima, commonly known as ‘Dhasingre’ in Nepal. The structures were elucidated on the basis of physical, chemical and spectroscopic methods. Among known compounds, five compounds (36 and 8) were isolated for the first time from G. fragrantissima. In vitro antioxidant activity of all the isolated compounds was evaluated by 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging assay. Dhasingreoside (1) and other compounds (26) showed significant free radical-scavenging activity.  相似文献   

6.
This paper intends to identify the antimicrobial activity compounds from the deciduous leaves of Malus doumeri (Dong Li Tea) by HPLC-ESI-QTOF-MS/MS. The ethanol extracts of Malus doumeri were partitioned into petroleum ether, dichloromethane, ethyl acetate, n-butanol and water fraction, respectively. The antimicrobial screening experiments showed that ethyl acetate fraction has a certain antibacterial activity by inhibition zone method in vitro. And then we used the HPLC-ESI-QTOF-MS/MS method to verify the identities of bioactive compounds. Finally, 41 compounds were determined and 11 of which were firstly reported in this plant. Notably, compounds (32, 34, 38) are new dihydrochalcones, and three chlorogenic acid analogues (10, 13, 17) may be potential antimicrobial active ingredient. Which is of great significance to the isolation of novel compounds and the discovery of new natural preservative candidates from the deciduous leaves of Malus doumeri.  相似文献   

7.
Two-parameter equation correlations are reported for radical reactions of aromatic compounds. In these correlations polar and resonance substituent constants identical with the substituent constants of aliphatic compounds were used. The equations correlate the rate constants for H abstraction reactions and for the addition of a variety of free radicals to the ortho-, meta-, and para-substituted aromatic compounds. Besides, they correlate parameters of the spectra for substituted aromatic radicals. The correlations show that the effects of para substituents on the reactions studied are nearly entirely resonance effects, whereas for the meta- and ortho-substituted compounds polar (inductive) effects become essential. Application of the two-parameter correlations permits also to determine the structure of transition states (σ or π-complex) in free-radical reactions.  相似文献   

8.
The mass spectra of some α-substituted phenyl-α,α′-dimethoxyl ketones (compounds 1) and their 2,4-dinitrophenylhydrazones (compounds 2) and semicarbazones (compounds 3) have been studied. The characteristic fragments at m/z (M ? 73) from compounds 1, m/z (M ? 253) from compounds 2 and m/z (M ? 130) from compounds 3 are abundant and proposed to be [ArCROCH3]+. Fragmentations yielding [M+ ? 49] from compounds 2 are abnormal and probably involve the methoxyl and nitro groups. The intense peak at m/z 130 due to [CH3OCH2CNNHCONH2]+ from compounds 3 corresponds to α-cleavage of the molecular ion. Some other fragments from these new compounds are interpreted in this paper.  相似文献   

9.
Abstract

Two new compounds, (7R, 2E, 5E)-3,5,7-trimethyl-2,5-octadienedioic-8-methyl ester (1) and neovasipyridone G (3), together with a new natural product compound (7R,2E,5E)-3,5,7-trimethyl-2,5-octadienedioic acid (2), and six known compounds (4–9) were isolated from Penicillium sp. SYPF7381. Their structures were elucidated on the basis of extensive spectroscopic analysis, and the absolute configurations of compounds 1 and 2 were determined by optical rotation. The absolute configuration of compound 3 was determined by means of electronic circular dichroism (ECD) calculation. In addition, the in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. Furthermore, the structure-antiinflammation activity relationships for these isolated compounds were summarized based on the experimental as well as the docking results.  相似文献   

10.
Three new polyphenolic compounds including a dihydrophenanthrene, pleioanthrenin ( 1 ), two bibenzyls, pleiobibenzynin A ( 2 ) and B ( 3 ), and a new cycloartane triterpenoid, (24R)‐cyclomargenyl p‐coumarate ( 4 ), together with eight known compounds, were isolated from the pseudobulbs of Pleione formosana. The structures of the new compounds were elucidated by extensively spectroscopic analysis.  相似文献   

11.
The relationship between density of energetic azole‐based compounds and their molecular structure is investigated through quantitative structure‐property relationship (QSPR) approach. The methodology of this work introduces a new model, which related density of azole‐based energetic compounds to the optimum elemental composition, the degree of unsaturation (DoU) of the compounds, presence of nitroimino group in the structural formula, as well as several non‐additive structural parameters. The presence of nitroimino functional group and also increasing the value of nO/nN in the formula of these compounds can enhance their density. The correlation is derived on the basis of experimental density values of 100 azole‐based energetic compounds with different molecular structure as training set. The determination coefficient of the new correlation is 0.923. Also, it has the root mean square deviation (RMSD) and the average absolute deviation (AAD) of 0.038 and 0.030 g · cm–3, respectively. In addition, the correlation gives good predictions for further 25 azole‐based energetic compounds as test set (Q2EXT = 0.901). The predictive ability of the correlation is checked using a cross validation method (Q2LMO = 0.918). The proposed method can also apply for designing novel azole‐based energetic compounds.  相似文献   

12.
A new dihydrochalcone glycoside, phloretin-4-O-β-D-glucopyranoside (1), together with seven known flavonoids (2–8), were isolated from the stems of Homalium stenophyllum. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. The known compounds (2–8) were isolated from the genus Homalium for the first time. All compounds were evaluated for their antibacterial activities against six pathogenic bacteria in vitro.  相似文献   

13.
Three new compounds, 2,4‐dimethoxy‐6‐methylbenzene‐1,3‐diol ( 1 ), salmoquinone ( 2 ), and 3‐(4‐hydroxyphenyl)‐4‐isobutyl‐1H‐pyrrole‐2,5‐dione ( 3 ), together with six known compounds, 2‐methoxy‐6‐methyl‐p‐benzoquinone ( 4 ), 2,3‐dimethoxy‐5‐methyl‐p‐benzoquinone ( 5 ), 2‐hydroxy‐5‐methoxy‐3‐methyl‐p‐benzoquinone ( 6 ), eburcoic acid ( 7 ), fomefficinic acid C ( 8 ), and a pyrroledione ( 9 ), were isolated from the mycelium of Antrodia salmonea. The structures of these compounds were elucidated by spectrometric analyses including IR, NMR, and MS. Among these compounds, 4 and 5 exhibited cytotoxicity against KB, HepG2, and H2058 cell lines.  相似文献   

14.
A series of commercial organotin compounds was screened for efficacy against the three insect species Dysdercus cingulatus (cotton stainer), Anophelese stephensi (mosquito) and Musca domestica (house fly). Tributyltin species in the general order Bu3SnCl>(Bu3Sn)2O>Bu3Sn(linoleate) were more effective than two triphenyltin compounds. Tricyclohexyltin hydroxide, dimethyltin chloride, phenyltin trichloride and a diethyltin dichloridephenanthroline adduct were less effective.  相似文献   

15.
The semiconductive properties of a series of pyrenyl polyenes of the type R-(CH=CH)n-R, are studied as a function of the adsorption of different amount of a vapour. With regard to the compensation temperature (T 0) the compounds are divided into two groups. For compounds which have odd number of double bonds,T 0 is infinite and in compounds having even number double bonds,T 0 is finite.T 0 for II2 is higher while that of II4 is lower than the experimental temperature. DifferentT 0 for the compounds having odd or even number of double bonds suggests a physical basis for the compensation rule, which we believe, is related to the molecular and crystalline structure of the compounds  相似文献   

16.
Abstract

High-performance liquid chromatography (HPLC) plays an important role in testing the pharmaceutically active compounds. In despite of the advantages of HPLC, thin-layer chromatography (TLC) retains its applicability to the different experimental tasks. The experimental conditions which allow hydrophilic interactions in the chromatographic system were tested in the HPLC and TLC systems for ivabradine, its related compounds, diltiazem and verapamil. Under the TLC conditions, retention behavior of the investigated compounds was tested on silica gel modified with cyanopropyl ligands as stationary phase and acetonitrile?+?methanol containing 25% v/v formic acid. Under the HPLC conditions, we used silica gel modified with cyanopropyl ligands as a column packing and the acetonitrile + 0.25% aqueous solution of formic acid as mobile phase. Retention behavior of the investigated analytes depending on the changing volume fractions of the mobile phase modifier was characterized both for TLC and HPLC data sets by the Soczewiński–Wachtmeister equation. Linear relationships were established between the retention coefficients characterizing the retention mechanism (RM0/m, logk0/m) and molecular properties of the investigated compounds. The Quantitative Structure Retention Relationship (QSRR) modeling was performed with the use of the stepwise multiple linear regression, in order to select molecular properties which influence retention.  相似文献   

17.
Two new alkaloids, ranaconidine (=20‐ethyl‐1α,14α,16β‐trimethoxyaconitane‐4,7,8,10‐tetrol; 1 ) and N‐(chloromethyl)taspine (=1‐[2‐(N‐(chloromethyl)‐N,N‐dimethylaminium)ethyl]‐3,8‐dimethoxybenzopyrano[5,4,3‐cde]benzopyran‐5,10‐dione; 2 ), together with two known compounds, i.e., benzethonium chloride ( 3 ) and ranaconine ( 4 ) were isolated from the roots of Aconitum sinomontanum Nakai . The structures of the compounds were elucidated on the basis of spectral evidences and in the comparison with previously published data.  相似文献   

18.
Phytochemical investigations on a marine green alga Ulva lactuca led to the isolation of two new compounds (E)-6-heptacosen-5-one (1) and (E)-6-octadecen-5-ol (2), along with four known compounds, (Z)-10-hexacosene (3), docosanoic acid (4), palmitic acid (5), and isofucosterol (6). Compounds 3 and 4 were isolated for the first time from this species. The structures of the compounds were deduced with the help of modern spectroscopic techniques.  相似文献   

19.
Two new esters, methyl 4‐(prenyloxy)dihydrocinnamate and methyl 4‐(geranyloxy)dihydrocinnamate, together with fourteen known compounds have been isolated from the stem bark of Zanthoxylum pistaciiflorum. The structures of two new compounds were determined through spectral analyses. Among the isolates, four compounds exhibited effective cytotoxicities against P‐388 and HT‐29 cell lines in vitro.  相似文献   

20.
The two previously unreported esters 1 and 2 of pentane‐2,4‐diol and p‐coumaric acid (=3‐(4‐hydroxyphenyl)prop‐2‐enoic acid) along with 13 known compounds including 6 oleanane‐ and ursane‐type triterpenoids were isolated from MeOH extracts of the stems of Vaccinium myrtillus. The structures of the new compounds were assigned as (2S,4R)‐4‐(β‐D ‐glucopyranosyloxy)pentan‐2‐yl (2E)‐p‐coumarate ( 1 ) and its aglycone 2 on the basis of 1D‐ and 2D‐NMR spectroscopic analyses of the isolated and synthesized compounds and molecular modelling experiments. This is the first report on the occurrence of a chiral pentane‐2,4‐diol linker between the phenol‐derived acid and a glycoside part in natural products.  相似文献   

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