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1.
A one‐pot synthesis of pyrrolo[1,2‐a]quinolin‐1‐ones has been developed from the reactions of 5‐hydroxy‐1‐arylpyrrolidin‐2‐ones with 1,3‐dicarbonyl compounds under the promotion of H3PO4/P2O5 or HOAc/H2SO4. The pyrrolo[1,2‐a]quinolin‐1‐ones are formed by two‐step reactions, that is, the coupling of N‐acyliminium ion intermediates produced from 5‐hydroxy‐1‐arylpyrrolidin‐2‐ones with 1,3‐dicarbonyls and subsequent Friedel–Crafts reactions of the resulting ketone with the aryl ring.  相似文献   

2.
In this study phenylselenocyanate and some of its derivatives (o‐Cl, p‐Cl, p‐Br, o‐NO2, p‐NO2, o‐CH3, p‐CH3, o‐COOH, p‐COOH, p‐OCH3 substituted) were synthesized ( 3a–3j ). The synthesized compounds were converted to 5‐aryl‐1H‐tetrazole ( 4a–4j ), by Et3N ċ HCl‐NaN3 in toluene, which are a new series of phenylselanyl‐1H‐tetrazoles. The structure of all the presently synthesized compounds were confirmed using spectroscopic methods (FTIR, 1H NMR, MS). © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:255–258, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20293  相似文献   

3.
New highly cytotoxic 1‐{3‐[1‐(5‐organylsilyl‐furan‐2‐yl)silinan‐1‐yl]propyl}amines and some trimethylgermyl analogues (IC50 1–7 μg mL?1) have been synthesized by a hydrosilylation reaction of aliphatic and heterocyclic N‐allylamines in the presence of Speier’s catalyst. The effects of the silacycle, the element‐organic substituent in position 5 of the furan ring, and the structure of the amine on the cytotoxicity of the new compounds have been studied.  相似文献   

4.
A four‐step synthesis of 1‐substituted 5‐(2‐aminophenyl)‐1H‐pyrazoles 5 as a novel type of histamine analogs and versatile building blocks for further transformations was developed. The synthesis starts from commercially available 2‐nitroacetophenone ( 12 ), which is converted into the enamino ketone 13 as the key intermediate. Cyclization of the key intermediate 13 with monosubstituted hydrazines 14a – 14l afforded the 5‐(2‐nitrophenyl)‐1H‐pyrazoles 17a – 17l . Finally, catalytic hydrogenation of the nitro compounds 17a, 17c – 17e , and 17g – 17j furnished the title compounds 5a, 5c – 5e , and 5g – 5j , respectively, in good yields. As demonstrated by some further transformations, additional functionalization of compounds 17 and 5 is feasible, either by electrophilic substitution at C(4) of the pyrazole ring, or at the NH2 group.  相似文献   

5.
In order to find novel bleaching herbicide lead compounds, a series of novel 3‐aryl‐4‐substituted‐5‐[3‐(trifluoromethyl)phenoxy]‐1,2,4‐triazoles were designed and synthesized by the multi‐step reactions. N‐(Arylformamido)phenylthioureas undergo ring closure in the presence of sodium hydroxide to generate 3‐aryl‐4‐substituted‐4H‐[1,2,4]triazol‐5‐thiols 1 , which reacted with methyl sulfate in the presence of K2CO3 to give 3‐aryl‐5‐methylsulfanyl‐4‐substituted‐4H‐[1,2,4]triazoles 2 . The target compounds 4 were synthesized by the oxidation of 2 in the presence of H2O2 and Na2WO4, followed by the substitution with 3‐(trifluoromethyl)phenol in moderate to good yields. Their structures were confirmed by IR, 1H NMR, EI–MS, and elemental analyses. The preliminary bioassay indicated that some of them displayed moderate to good selective herbicidal activity against Brassica campestris L at the concentration of 100 µg/mL. Compounds 4c and 4i possessed 75.0% and 82.6% inhibition against Brassica campestris L at the concentration of 100 µg/mL. However, the target compounds 4 showed weak herbicidal activity against Echinochloa crus‐galli at the concentration of 100 and 10 µg/mL.  相似文献   

6.
In this study, we report the synthesis a series of novel 2‐[N‐(1H‐tetrazol‐5‐yl)‐6,14‐endo‐etheno‐6,7,8,14‐tetrahydrothebaine‐7α‐yl]‐5‐phenyl‐1,3,4‐oxadiazole derivatives ( 7a – e ) which have potential opioid antagonist and agonist. The substitution reaction of 6,14‐endo‐ethenotetrahydrothebaine‐7α‐carbohydrazide with corresponding benzoyl chlorides gave diacylhydrazine compounds 4a – e in good yields. The treatment of compounds 4a – e with POCl3 caused the conversion of side‐chain of compounds 5a – e into 1,3,4‐oxadiazole ring at C(7) position; thus, compounds 5a – e were obtained. Subsequently, cyanamides ( 6a – e ) were prepared from compounds 5a – e and then compounds 7a – e were synthesized by the azidation of 6a – e with NaN3. The structures of the compounds were established on the basis of their IR, 1H NMR, 13C APT, 2D‐NMR (COSY, NOESY, HMQC, HMBC) and high‐resolution mass spectral data.  相似文献   

7.
A new series of pyrazolone based azo acid dyes (3a–g) has been synthesized starting from 1‐(p‐sul‐phophenyl)‐3‐methyl‐5‐pyrazolone (1). The synthetic methodology included the nitrosation of p‐sulphophenyl methyl pyrazolone followed by reduction, diazotization and coupling with Naphthol AS derivatives (2a–f), in alkaline medium to yield different acid dyes. Multichromic metal complexes of these dyes (5a–f, 6a–f and 7a–f) with 3d transition metals Chromium, Iron and Copper were also synthesized. The structures of all of newly synthesized compounds were confirmed by analytical data and spectroscopic techniques. The synthesized dyes were applied on leather to assess their light fastness, wash fastness and rubbing fastness and were shown to exhibit high values of 4–5 for majority of dyes.  相似文献   

8.
Chiral 2‐amino‐butanols ( 4 and 5 ) were obtained via the isolation of diastereomeric salt. Then, chiral compounds ( 6 – 9) were synthesized by a sequential procedure involving condensation of chiral 2‐amino‐butanol with ketone and dichloroacetyl chloride. All the compounds were characterized by IR, 1H NMR, 13C NMR, and element analysis. The absolute configurations of ( S )‐ 8 was determined by X‐ray crystallography.  相似文献   

9.
Imidazo[4,5‐c ]pyrazole derivatives ( 3a–f , 4a–f , and 5a–f ) were efficiently synthesized by one‐pot three‐component reactions using CeO2–MgO as the catalyst. The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and mass spectroscopic analyses. The in vitro antimicrobial activity of the synthesized compounds against various bacterial and fungal strains was screened. Compound 3b was highly active [minimum inhibitory concentration (MIC): 0.5 μg/mL] against Gram‐positive Staphylococcus aureus , and compounds 3b , 3f , 4d , and 4e were highly active (MIC: 0.5, 2, 2, and 0.5 μg/mL, respectively) against Gram‐negative Pseudomonas aeruginosa and Klebsiella pneumoniae , relative to standard ciprofloxacin in the antibacterial activity screening. Compounds 3b and 4f were highly active (MIC: 4 and 0.5 μg/mL, respectively) against Aspergillus fumigatus and Microsporum audouinii in the antifungal activity screening compared with the clotrimazole standard.  相似文献   

10.
The reaction of SnPh3Li with X(CH2)n O–THP (THP = tetrahydro‐2H ‐pyran‐2‐yl; n  = 3, 4, 6, 8, 11; X = Cl, Br) afforded organotin(IV) compounds with the general formula Ph3Sn(CH2)n O–THP ( 1 – 5 ). The tetraorganotin(IV) compounds were characterized using multinuclear NMR and infrared spectroscopies and high‐resolution mass spectrometry. Anticancer activity of the synthesized compounds was tested in vitro against the A2780 (ovarian), A549 (lung), HeLa (adenocarcinoma) and SW480 (colon) tumour cell lines with SRB assay. The in vitro investigations revealed that when a shorter chain was present a higher activity was achieved; however compounds 1 – 5 were found to be less active than cisplatin. In addition, the most active compound, 1 , enters A2780 cells and causes apoptosis by triggering both intrinsic and extrinsic caspase pathways.  相似文献   

11.
《化学:亚洲杂志》2017,12(22):2908-2915
A series of unsymmetrical (D‐A‐D1, D1‐π‐D‐A‐D1, and D1‐A1‐D‐A2‐D1; A=acceptor, D=donor) and symmetrical (D1‐A‐D‐A‐D1) phenothiazines ( 4 b , 4 c , 4 c′ , 5 b , 5 c , 5 d , 5 d′ , 5 e , 5 e′ , 5 f , and 5 f′ ) were designed and synthesized by a [2+2] cycloaddition–electrocyclic ring‐opening reaction of ferrocenyl‐substituted phenothiazines with tetracyanoethylene (TCNE) and 7,7,8,8‐tetracyanoquinodimethane (TCNQ). The photophysical, electrochemical, and computational studies show a strong charge‐transfer (CT) interaction in the phenothiazine derivatives that can be tuned by varying the number of TCNE/TCNQ acceptors. Phenothiazines 4 b , 4 c , 4 c′ , 5 b , 5 c , 5 d , 5 d′ , 5 e , 5 e′ , 5 f and 5 f′ show redshifted absorption in the λ =400 to 900 nm region, as a result of a low HOMO–LUMO gap, which is supported by TD‐DFT calculations. The electrochemical study exhibits reduction waves at low potential due to strong 1,1,4,4‐tetracyanobuta‐1,3‐diene (TCBD) and cyclohexa‐2,5‐diene‐1,4‐ylidene‐expanded TCBD acceptors. The incorporation of cyclohexa‐2,5‐diene‐1,4‐ylidene‐expanded TCBD stabilized the LUMO energy level to a greater extent than TCBD.  相似文献   

12.
The title compounds, rac‐(1′R,2R)‐tert‐butyl 2‐(1′‐hydroxyethyl)‐3‐(2‐nitrophenyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C17H20N2O6, (I), rac‐(1′S,2R)‐tert‐butyl 2‐[1′‐hydroxy‐3′‐(methoxycarbonyl)propyl]‐3‐(2‐nitrophenyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C20H24N2O8, (II), and rac‐(1′S,2R)‐tert‐butyl 2‐(4′‐bromo‐1′‐hydroxybutyl)‐5‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate, C13H20BrNO4, (III), are 5‐hydroxyalkyl derivatives of tert‐butyl 2‐oxo‐2,5‐dihydropyrrole‐1‐carboxylate. In all three compounds, the tert‐butoxycarbonyl (Boc) unit is orientated in the same manner with respect to the mean plane through the 2‐oxo‐2,5‐dihydro‐1H‐pyrrole ring. The hydroxyl substituent at one of the newly created chiral centres, which have relative R,R stereochemistry, is trans with respect to the oxo group of the pyrrole ring in (I), synthesized using acetaldehyde. When a larger aldehyde was used, as in compounds (II) and (III), the hydroxyl substituent was found to be cis with respect to the oxo group of the pyrrole ring. Here, the relative stereochemistry of the newly created chiral centres is R,S. In compound (I), O—H...O hydrogen bonding leads to an interesting hexagonal arrangement of symmetry‐related molecules. In (II) and (III), the hydroxyl groups are involved in bifurcated O—H...O hydrogen bonds, and centrosymmetric hydrogen‐bonded dimers are formed. The Mukaiyama crossed‐aldol‐type reaction was successful when using the 2‐nitrophenyl‐substituted hydroxypyrrole, or the unsubstituted hydroxypyrrole, and boron trifluoride diethyl ether as catalyst. The synthetic procedure leads to a syn configuration of the two newly created chiral centres in all three compounds.  相似文献   

13.
Chloro, fluoro, and nitro derivatives of 7‐amino‐5‐aryl‐6‐cyano‐5H‐pyrano pyrimidin‐2,4‐diones were produced by reacting malononitrile, barbituric acid, and aromatic aldehydes together with a DABCO catalyst in an aqueous one‐pot reaction. This is the first report of these compounds being synthesized with DABCO as a catalyst, which produced the compounds in yields in excess of 90%. The 2,4‐difluoro derivative ( 11 ) was novel. The structures of the synthesized compounds were elucidated by means of 1H, 13C, and 2D NMR spectroscopy. Compound 2 (2‐Cl derivative) had MBC values of <200μM against both Staphylococcus aureus and MRSA, and the 2‐nitro derivative 5 had an MBC of 191μM against the Gram–ve Escherichia coli. The synthesized compounds were also tested for their anticancer activity against a HeLa cell line, where all the compounds showed better activity (IC50 values between 129μM and 340μM) than 5‐fluorouracil, a commonly known anticancer drug.  相似文献   

14.
The cyclization of aryl ketone anilides 3 with diethyl malonate to affords 4‐hydroxy‐6‐phenyl‐6H‐pyrano[3,2‐c]‐pyridin‐2,5‐diones 4 in good yields. 3‐Acetyl‐4‐hydroxy‐1‐phenylpyridin‐2(1H)‐ones 5 are obtained by ring‐opening reaction of 4‐hydroxy‐6‐phenyl‐6H‐pyrano[3,2‐c]‐pyridin‐2,5‐diones 4 in the presence of 1,2‐diethylene glycol. The reaction of 3‐acetyl‐4‐hydroxy‐1‐phenylpyridin‐2(1H)‐ones 5 with hydroxylamine hydrochloride produces 4‐hydroxy‐3‐[N‐hydroxyethanimidoyl]‐1‐phenylpyridin‐2(1H)‐ones 6 from which 3‐alkyloxyiminoacetyl‐4‐hydroxy‐1‐phenylpyridin‐2(1H)‐ones 7 are obtained by reacting with alkyl bromides or iodides in the presence of anhydrous potassium carbonate with moderate yields. The similar compounds can be synthesized on refluxing 3‐acetyl‐4‐hydroxy‐1‐phenylpyridin‐2(1H)‐ones 5 with substituted hydroxylamine hydrochloride in the presence of sodium bicarbonate with good yields. Most of the synthesized compounds are characterized by IR and NMR spectroscopic methods.  相似文献   

15.
The Biginelli‐type compounds, 5‐unsubstituted 3,4‐dihydropyrimdin‐2(1H)‐ones were synthesized by a one‐pot three‐component condensation of aromatic aldehydes, aromatic ketones and urea in the presence of SnCl4 · 5H2O under solvent‐free conditions. The advantages of this method are short reaction time (4–10 min), excellent yields (74–97%), inexpensive catalyst and solvent‐free conditions. A plausible mechanism was proposed.  相似文献   

16.
New series of quinoxaline derivatives ( 4a–4h ) were synthesized by treating 2‐chloro‐3‐hydrazinyl quinoxalin ( 3 ) with various anilines. Compound 3 was obtained from the 2,3‐dichloroquinoxaline 2 which was prepared from 4‐dihydroquinoxaline‐2,3‐dione ( 1 ). All synthesized compounds ( 4a–4h ) were characterized by various spectral techniques, that is, IR, 1H‐NMR, mass spectroscopy, and elemental analysis and completion of reaction were confirmed by TLC. In vitro antimicrobial activity of synthesized compounds was evaluated using disc diffusion assay against gram‐positive and gram‐negative microbial strains, and then, the minimum inhibitory concentration and IC50 values of compounds were also determined. The results of antimicrobial study revealed that compounds 4e , 4g , and 4a were active and exhibited better inhibitory activities as compared with standard drug amoxicillin. Docking studies were performed by using Argus lab, and all the compounds exhibited good docking scores between −9.53 and −7.94 kcal/mol against dihydrofolate reductase protein fragment from Staphylococcus aureus (PDB ID‐4XE6). Among all compounds, 4e has shown the maximum docking score and found in agreement to in vitro studies.  相似文献   

17.
A series of novel N‐(2‐(pyridine‐4‐yl)‐1H‐pyrrolo[3,2‐c]‐pyridin‐6‐yl‐(substituted)‐sulfonamide derivatives were synthesized from 2‐bromo‐6‐nitro‐1H‐pyrrolo[3,2‐c]pyridine through a series of reactions including Suzuki reaction, reduction, protection, and sulfonamide coupling. All the synthesized compounds were screened for anticancer activity against MCF‐7, HeLa, A‐549, and Du‐145 cancer cell lines by the MTT assay. The preliminary bioassay suggests that most of the compounds show antiproliferation with different degrees. Doxorubicin was used as a positive control. Among the synthesized compounds, 8d and 8h were most active compared with the standard in cell line data. The synthesized compounds 8d and 8h show IC50 values in the range of 1.88–5.16 μM for all the cell lines. Compounds 8d and 8h were further studied for a panel of eight human kinase at 10 μM concentrations and the result shows 64% to 70% inhibitions for both Aurora‐A and Aurora‐B kinase.  相似文献   

18.
In the present investigation, a series of 4‐((3‐(trifluoromethyl)‐5,6‐dihydro‐[1,2,4]triazolo[4,3‐a]pyrazin‐7(8H)‐yl)methyl)benzenamine analogs 6a–o were synthesized and characterized by IR, NMR (1H and 13C), and mass spectra. All newly synthesized compounds 6a–o were prepared under conventional and microwave irradiation methods. These compounds obtained in higher yields and in shorter reaction times in the microwave irradiation method when compared with the conventional method. Synthesized compounds 6a–o were inspected for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Ra using an established XTT reduction menadione assay. Among the screened compounds, 6i (IC50: 1.82 μg/mL), 6j (IC50: 1.02 μg/mL), and 6k (IC50: 1.59 μg/mL) showed excellent activity. Furthermore, compound 6i showed MIC90 value of 16.02 μg/mL. In summary, the results indicate the identification of some novel, selective, and specific inhibitors against M. tuberculosis that can be explored further for the potential antitubercular drug.  相似文献   

19.
The tautomerism of the synthesized 3‐arylpyrimido[4,5‐c]pyridazine‐5,7(6H,8H)‐diones ( 1a–d ) and 3‐aryl‐7‐thioxo‐7,8‐dihydro‐6H‐pyrimido[4,5‐c]pyridazine‐5‐ones ( 2a–d ) was studied in dimethyl sulfoxide (DMSO)‐d6. 1H NMR spectra of 1a–d showed a clustered water molecule in the structure backbone that is attached by strong intermolecular H bonding. The relation between the temperature and H bonding of the clustered water molecule with 1a was also studied as representative. The relation between the electronegativity (χ) of the substituent on phenyl ring and the chemical shifts of clustered water protons in 1a–d was also studied. All of 1a–d and also 2d compounds existed in lactam ( I ) form, whereas 2a–c compounds have two distinguished tautomers in DMSO‐d6 [lactam ( I ) and lactim ( II ) forms]. The solvent‐substrate proton exchange was examined in compounds 1a–d and 2a–d by adding one drop of D2O. All compounds (except 1d ) showed proton/deuterium exchange of the clustered water protons in DMSO by adding one drop of D2O. Some compounds (but not all of them) that are easily soluble in DMSO‐d6 containing D2O showed isotopic splitting (β‐isotope effect) in their 13C NMR spectra. Among them, compound 1a was the best evidence to help the spectral assignments and structure determination of predominant tautomer by carbon‐13 splitting (β‐isotope effect). Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

20.
In an attempt to achieve promising cytotoxic agents, a series of new (Z)‐3‐benzyl‐5‐((1‐phenyl‐3‐(3‐((1‐substituted phenyl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)‐1H‐pyrazol‐4‐yl)methylene)thiazolidine‐2,4‐diones 10 a‐n were designed, synthesized, and characterized by 1H NMR, 13C NMR, IR, and ESI‐MS techniques. These compounds synthesized from appropriate reaction procedures with better yields. All the novel synthesized compounds 10a‐n were evaluated for their cytotoxic activity against the MCF‐7 cell line (Human breast cancer cell line) at different concentrations of 0.625, 1.25, 2.5, 5, and 10 μM, respectively. The cytotoxic evaluation assay is presented in terms of IC50 values and percentage cell viability reduction compared against standard drug cisplatin. Among all novel synthesized compounds 10a‐n , some of the representative analogues particularly 10g and 10e exhibit remarkable cytotoxic activity with IC50 values 0.454 and 0.586 μM, comparable to that of the standard drug cisplatin, and some analogues 10d , 10f , 10k, and 10m also have shown significant activity.  相似文献   

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