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1.
Abstract

Phytochemical study on the extract of Vietnamese medicinal plant Helicteres hirsuta Lour. has led to the isolation and structural elucidation of twelve secondary metabolites, 3-O-trans-caffeoylbetulinic acid (1), 3β-benzoylbetulinic acid (2), betulinic acid methyl ester (3), betulinic acid (4), lupeol (5), 4-hydroxybenzoic acid (6), 3,4-dihydroxybenzoic acid methyl ester (7), 4-hydroxy-3,5-dimethoxybenzoic acid (8), 5,8-dihydroxy-7,4′-dimethoxyflavone (9), isoscutellarein 4’-methyl ether 8-O-β-D-glucopyranoside (10), methyl caffeate (11) and stigmasterol (12). Especially, compound 2 was reported as a new natural product. Their structures were elucidated by a combination of 2D NMR and ESI-FT-ICR-MS spectroscopies. Furthermore, eight compounds were tested for their cytotoxicity against five cancer cell lines (Hela, HepG2, SK-LU-1, AGS and SK-MEL-2). The results showed that compounds (1, 3-5, 9) have moderate activities. This is the first study on the chemical constituents and their cytotoxicity of the Vietnamese Helicteres hirsuta L.  相似文献   

2.
Five phenyl compounds, vanillin (1), methyl trans-ferulate (2), trans-p-coumaric acid methyl ester (3), N-benzoyltryptamine (4), and N-(trans-cinnamoyl)tryptamine (5), were isolated from the roots of Oryza sativa L. and identified on the basis of spectroscopic data. Compounds 3 and 5 showed strong inhibition effect on melanin production in murine B16-F10 melanoma cells and tyrosinase activity. Also, the quantitative analysis of the compounds was carried out using LC/MS/MS experiment. Compounds 3 and 5 could be used as skin-whitening agents.  相似文献   

3.
Six meta‐substituted salicylaldehyde compounds have been prepared in 68–90% yields by the Suzuki–Miyaura coupling reaction using 3‐bromo‐5‐t‐butylsalicylaldehyde (1a) and arylboronic acids (2af) as reactants. Among the obtained products, 3‐(4‐fluorophenyl)‐5‐t‐butylsalicylaldehyde (3b), 3‐(4‐methylphenyl)‐5‐t‐butylsalicylaldehyde (3d), 3‐(1‐naphthyl)‐5‐t‐butylsalicylaldehyde (3e), and 3‐(2‐naphthyl)‐5‐t‐butylsalicylaldehyde (3f) have not been reported so far. A series of new Schiff base ligands (L1L10) were obtained in 51–89% yields from these salicylaldehyde derivatives.  相似文献   

4.
Abstract

An aliphatic ester of hydroxysalicylic acid (6), reported for the first time from a natural source in addition to five known compounds were isolated from the fermented Carica papaya L. preparation, a commercialized functional food. The known compounds were identified as 5-hydroxymethylfurfuraldehyde (1), trans-caffeic acid (2), butyl 4-hydroxybenzoate (butylparaben) (3), lycopene (4), benzyl isothiocyanate (5). Compounds 1 and 3 were reported for the first time from Papaya fruits through this study. The new compound showed a moderate antioxidant activity and a potent hair growth stimulating activity in vitro.  相似文献   

5.
Four‐component reaction of aminodiazines (2‐aminopyrimidine and 2‐aminopyrazine), glyoxal, formaldehyde, and methanol yields trans‐4,5‐dimetoxy‐1,3‐bis(2‐pyrimidinyl)imidazolidine (5a) and trans‐4,5‐dimetoxy‐1,3‐bis(2‐pyrazinyl)imidazolidine (5b), respectively. Changing methanol to acetonitrile leads to the formation of the corresponding 1,3‐bis(2‐pyrimidinyl) and‐1,3‐bis(2‐pyrazinyl)‐ derivatives of trans‐4,5‐dihydroxyimidazolidine (6). Details of the proposed mechanism are discussed.  相似文献   

6.
A new diarylheptanoid, namely trans-(4R,5S)-epoxy-1,7-diphenyl-3-heptanone (1), and a new natural product, 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-hepta-4E,6E-dien-3-one (2), were obtained from the aqueous extract of Alpinia officinarum Hance, together with three other diarylheptanoids, 5-hydroxy-1,7-diphenyl-3-heptanone (3), 1,7-diphenyl-4E-en-3-heptanone (4) and 5-methoxy-1,7-diphenyl-3-heptanone (5). The structures were characterised mainly by analysing their physical data including IR, NMR and HRMS. This study highlights that the 4,5-epoxy moiety in 1 is rarely seen in diarylheptanoids. In addition, the five isolates were tested for their differentiation activity of 3T3-L1 preadipocytes. The results showed that these compounds could dose-dependently promote adipocyte differentiation without cytotoxicity (IC50 > 100 μM).  相似文献   

7.
A new butanolide, isoreticulide ((4R,3E)-4-hydroxy-5-methylene-3-octadecylidenedihydrofuran-2-one) (1), along with nine compounds including one sesquiterpenoid, (3-methoxy-5H-9,11dioxabenzo[3,4]cyclohepta[1,2-f])inden-7-yl)-methanol (2); six benzenoids, p-hydroxybenzoic acid (3), p-hydroxybenzaldehyde (4), protocatechuic acid (5), ferulic acid (6), trans-methyl p-coumarate (7), and p-dihydrocoumaric acid (8), and two amides, N-trans-feruloyltyramine (9) and dihydroferuloyltyramine (10), were isolated from the leaves of Cinnamomum reticulatum Hayata (Lauraceae). These compounds were characterized and identified by physical and spectral evidence.  相似文献   

8.
Two efficient methods for the preparation of 2‐(2‐sulfanyl‐4H‐3,1‐benzothiazin‐4‐yl)acetic acid derivatives 3 under mild conditions have been developed. The first method is based on the reaction of 3‐(2‐isothiocyanatophenyl)prop‐2‐enoates 1a – 1c with thiols in the presence of Et3N in THF at room temperature, leading to the corresponding dithiocarbamate intermediates 2 , which underwent spontaneous cyclization at the same temperature by an attack of the S‐atom at the prop‐2‐enoyl moiety in a 1,4‐addition manner (Michael addition) to give 2‐(2‐sulfanyl‐4H‐3,1‐benzothiazin‐4‐yl)acetates in one pot. The second method involves treatment of 3‐(2‐isothiocyanatophenyl)prop‐2‐enoic acid derivatives 1b – 1d with Na2S leading to the formation of 2‐(2‐sodiosulfanyl‐4H‐3,1‐benzothiazin‐4‐yl)acetic acid intermediates 5 by a similar addition/cyclization sequence, which are then allowed to react with alkyl or aryl halides to afford derivatives 3 . 2‐(2‐Thioxo‐4H‐3,1‐benzothiazin‐4‐yl)acetic acid derivatives 6 can be obtained by omitting the addition of halides.  相似文献   

9.
The AcOEt‐soluble part of a MeOH extract from the whole plant of Erigeron bonariensis yielded two new rare‐class octulosonic acid derivatives, rel‐methyl (1R,2S,3S,5R)‐3‐(trans‐caffeoyloxy)‐7‐[(trans‐caffeoyloxy)methyl]‐2‐hydroxy‐6,8‐dioxabicyclo[3.2.1]octane‐5‐carboxylate ( 1 ) and 5,8‐di[Otrans‐caffeoyl]‐3‐deoxy‐β‐D ‐gluco‐oct‐2‐ulopyranosonosyl 4,8‐di[Otrans‐caffeoyl]‐3‐deoxy‐β‐D ‐gluco‐oct‐2‐ulopyranosidonic acid ( 2 ) along with a cyclohexanecarboxylic acid derivative, (1α,3β,4β,5β)‐1,4‐di‐3,5‐dihydroxy‐bis(trans‐caffeoyloxy)cyclohexanecarboxylic acid ( 3 ). The structures of these compounds were elucidated through ESI‐MS, and 1D‐ and 2D‐NMR spectroscopic techniques including 1H‐ and 13C‐NMR, HMQC or HSQC, and HMBC experiments.  相似文献   

10.
Aamer Saeed 《合成通讯》2013,43(9):1485-1490
An efficient microwave‐assisted synthesis of 8‐hydroxy‐6,7‐dimethoxy‐3‐hydroxymethyl isocoumarin (1), a metabolite of Streptomyces mobaraensis and structural relative of reticulol and cytogenin that possesses potent cyclic nucleotide phosphodiesterase inhibitor activity, is described. 3,4,5‐Trimethoxyhomophthalic acid (2) was condensed with acetoxyacetyl chloride under microwave irradiation and the acid hydrolysis of resulting 6,7,8‐trimethoxy‐3‐acetoxymethylisocoumarin (3) afforded the 6,7,8‐trimethoxy‐3‐hydroxymethylisocoumarin (4). Regioselective demethylation of the latter using magnesium iodide in THF yielded the title compound (1).  相似文献   

11.
The novel 8,14‐secoursatriene derivative 6 was synthesized starting from ursolic acid ( 1 ) via methyl esterification of the 17‐carboxylic acid group and benzoylation of the 3‐hydroxy group (→ 2 ; Scheme 1), ozone oxidation of the C(12)?C(13) bond (→ 3 ), dehydrogenation with Br2/HBr (→ 4 ), enol acetylation of the resulting carbonyl group (→ 5 ; Scheme 2), and ring‐C opening with the aid of UV light (→ 6 ). Ring‐C‐opened dienone derivative 7 of ursolic acid was also obtained via selective hydrolysis of 6 (Scheme 2). Both compounds 6 and 7 are key intermediates for the preparation of chiral decalin synthons from ursolic acid.  相似文献   

12.
A novel isoindole alkaloid named oleraisoindole (1), together with six known compounds, 7′-ethoxy-trans-feruloyltyramine (2), N-trans-feruloyltyramine (3), N-trans-feruloyl-3-methoxytyramine (4), N-trans-p-coumaroyltyramine (5) aurantiamide (6) and ferulic acid methyl ester (7) were isolated from Portulaca oleracea L. Compounds 2 and 7 were isolated for the first time from this plant. Compound 1 was identified using spectroscopic methods including HR-ESI-TOF-MS, 1D-NMR, 2D-NMR. It was tested in a nitric oxide (NO) inhibition assay and was shown to inhibit NO production in RAW 264.7 cells induced by LPS.  相似文献   

13.
The catalytic oxidative cyclocondensation of the o‐aminophenols 1af was investigated. The oxidants used were air/laccase, H2O2/horseradish peroxidase, H2O2/ebselen (3), and TBHP/diphenyl diselenide 4. The products obtained were 2‐amino‐3H‐phenoxazin‐3‐one—questiomycin A, its derivative 2b, and cinnabarinic acid and actinocin (2c,d). Substrates with methyl groups at 4 and 5 positions of benzene ring were converted to different dihydrophenoxazinones 2g,h. Compounds having chlorine atoms at the same positions underwent oxidation to planar phenoxa-zinones 2e,f with elimination of one hydrochloride molecule.  相似文献   

14.
N‐1‐Aroyl‐2‐{[(3‐methyl‐4(3H)‐quinazolinone‐2‐yl)methyl]anilino} ethano hydrazides (4), prepared from 2‐phenylaminomethyl‐3‐methyl‐4(3H)‐quinazolinone (1), underwent PPA‐catalyzed cyclization the to title compounds 5 in 51–67% yield.  相似文献   

15.
A simple and convenient one‐pot synthesis of 4‐(4‐chlorophenylazo)‐5‐methyl‐2‐aryl‐1,2‐dihydro‐pyrazol‐3‐ones (4a–j) has been carried out from 3‐arylsydnones (3a–j) by reaction with 2‐(4‐chlorophenyl)‐hydrazono‐3‐oxo‐butyric acid ethyl ester (2b). The 3‐arylsydnones are used as masked hydrazines in this reaction. Similarly, the 4‐arylazo‐2‐(7‐hydroxy‐4‐methyl‐2‐oxo‐2H‐chromen‐8‐ylmethyl)‐5‐methyl‐1,2‐dihydro‐pyrazol‐3‐ones (7a–j) were synthesized from 3‐[(7‐acetoxy‐4‐methyl‐8‐methylene)coumaryl]sydnone (5). All the newly synthesized compounds exhibited antimicrobial activity greater than the reference drugs used.  相似文献   

16.
A new lactam alkaloid named oleraciamide D (1), indentified as (5R)-4-(3-methoxy-4-hydroxyphenyl)-5-(4-hydroxyphenyl)-5,6-dihydropyridin-2(1H)-one, together with five known compounds, indole-3-aldehyde (2), portulacatone (3), N-trans-feruloyloctopamine (4), N-trans-feruloyl-3′-O-methyldopamine (5) and N-trans-feruloyltyramine (6) were isolated from Potulaca oleracea L. Among them, indole-3-aldehyde (2) was isolated from the medicine for the first time. The structure of the new alkaloid was elucidated via UHPLC-ESI-Q-TOF/MS, 1D NMR and 2D NMR. The five known compounds were established by comparing the 1H-NMR and 13C NMR with the reported literature. Oleraciamide D (1) showed cytotoxicity against SH-SY5Y cells when concentration at 50 uM by CCK-8 method.  相似文献   

17.
An efficient enantioselective synthesis of 3‐acetoxy transβ‐lactams 7a and 7b via [2+2] cycloaddition reactions of imines 4a and 4b , derived from a polycyclic aromatic amine and bicyclic chiral acid obtained from (+)‐car‐3‐ene, is described. The cycloaddition was found to be highly enantioselective, producing only trans‐(3R,4R)‐N‐azetidin‐2‐one in very good yields. This is the first report of the synthesis of enantiomerically pure transβ‐lactams 7a and 7b with a polycyclic aromatic substituent at N(1) of the azetidin ring.  相似文献   

18.
A novel sesquiterpenoid, subamol ((3-methoxy-5H-9,10-dihydroxybenzo[3,4]cyclohepta[1,2-f])inden-7-yl)methanol)) (1), along with six compounds, including one ionone: (+)-abscisic acid (2); and five benzenoids: syringaldehyde (3), trans-coumaric acid (4), cis-coumaric acid (5), vanillic acid (6), and p-hydroxybenzoic acid (7), were isolated from the leaves of Cinnamomum subavenium Miq (Lauraceae). These compounds were identified and characterized by physical and spectral evidence.  相似文献   

19.
In continuing search for novel cell differentiation agents, a series of derivatives of indole‐3‐acetic acid and indole‐3‐carboxylic acid were prepared and tested against HL‐60 cells for their differentiation and antiproliferation activities. Among them, N‐ethyl‐1‐benzylindole‐3‐carboxamide ( 14 ) was the most potent, whereas N‐methyl 1‐benzylindole‐3‐acetamide ( 5 ) and N‐methyl 1‐benzylindole‐3‐carboxamide ( 13 ) synergistically potentiated with all‐trans‐retinoic acid to induce cell differentiation as well as antiproliferation. Our results indicate that these compounds are effective cell differentiation and antiproliferation agents in combination with retinoic acid.  相似文献   

20.
A new caffeoylgluconic acid derivative, trans-caffeoyl-6-O-d-gluconic acid methyl ester (1), together with two known compounds named trans-caffeoyl-6-O-d-glucono-γ-lactone (2) and trans-caffeoyl-6-O-d-gluconic acid (3), was isolated from the nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth.. These compounds were isolated by various separation methods associated with the UPLC-Q-TOF-MS technique. Their structures were elucidated on the basis of extensive spectroscopic methods.  相似文献   

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