芝麻酚酰胺类衍生物的合成及抑菌活性

以芝麻酚为原料,经醚化、硝化、还原和酰胺化合成了9个未见报道的新型芝麻酚酰胺衍生物.其结构经~1H NMR和IR表征,并测定了其抑菌活性.初步生物活性测试结果表明,目标化合物对所有供试病菌均有一定的抑菌活性.4a_4对番茄灰霉病菌、棉花枯萎病菌、小麦赤霉病菌有较好的抑菌活性.4b_1对小麦赤霉病菌的抑制率达到95%;4b_2对番茄灰霉病菌和棉花枯萎病菌的抑制率达到90%以上;4b_3对番茄早疫病菌、番茄灰霉病菌、苹果腐烂病菌和棉花枯萎病菌的抑制率达到90%以上;4b_4对芹菜早疫病菌、番茄灰霉病菌、棉花枯萎病菌和小麦赤霉病菌的抑制率达到90%以上;4c_1对芹菜早疫病菌、番茄早疫病菌、番茄灰霉病菌、苹果腐烂病菌和棉花枯萎病菌的抑制率达到均达到90%以上.     

Synthesis and bioactivity of novel coumarin derivatives

A series of coumarin derivatives (6-8) containing (E)-methyl 2-(methoxyimino)-2-phenylacetate, (E)-2-(methoxyimino)-N-methyl-2-phenylacetamide and methyl methoxy(phenyl)carbamate were synthesized from substituted resorcinols (1) and substituted beta-keto esters (2) as starting material via cyclization and condensation reactions. The test results indicated that (E)-methyl 2-{2-[(3-hexyl-4-methyl-coumarin-7-yloxy)methyl]phenyl}-2-(methoxyimino)acetate (6f) was the optimal structure with good fungicidal activity against cucumber grey mold (CGM) giving 100% control at 100 mg L(-1) concentration, much higher than that of coumoxystrobin. Methyl 2-[(3,4-dimethyl-coumarin -7-yloxy)methyl]phenyl(methoxy)carbamate (8a) was another optimal structure with good fungicidal activity against wheat powdery mildew (WPM) showing 100% control at 50 mg L(-1) concentration, at the same level as that of the commercial kresoxim-methyl, and very significantly higher than that of coumoxystrobin (no control against WPM at 400 mg L(-1)).     

Synthesis and characterization of new thiazolidinones containing coumarin moieties and their antibacterial and antioxidant activities

New coumarin derivatives, namely (2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-phenylthiazolidin-3-yl)acetamide, N-(2-(3-methoxyphenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide, 2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-(2,3,4trimethoxyphenyl)thiazolidin-3-yl)acetamide and N-(2-(4-bromophenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide) were synthesized starting from 4-methyl-7-hydroxycoumarin. The structures of the obtained compounds were confirmed by analytical IR and NMR spectra to elucidate the different positions of protons and carbons and as well as theoretical studies (DFT/B3LYP). The new compounds were screened for antibacterial activity. Most of them are more active against E. coli S. aureus and B. subtilis than standard references.     

Synthesis and antifungal activities of novel trifluoroethane derivatives with coumarin,indole and thiophene

A series of novel 1-(β-coumarinyl)-1-(β-indolyl)-1-(α-thiophenyl)trifluoroethane derivatives 5aaa-5hdb were prepared by one-pot reaction from 3-(trifluoroacetyl)coumarin with indole and α-substituted thiophene. Their structures were confirmed by ¹H NMR, ¹³C NMR, ¹⁹F NMR, HRMS and X-ray single crystal diffraction, and their antifungal activities against F. moniliforme, F. graminearum, F. oxysporum, R. solani and P. nicotianae were evaluated. The title compounds displayed significant to moderate in vitro antifungal activity when compared to the standard drug triadimefon. Among the synthesized compounds, compound 5bfa showed the highest inhibitor rate of 83.5 % at 0.500 mg/mL against R. solani, while compound 5ada displayed the highest inhibitor rate of 73.3 % at 0.500 mg/mL against F. graminearum.     

Synthesis of novel coumarin and benzocoumarin derivatives and their biological and photophysical studies

Several derivatives of coumarin‐3N‐carboxamides ( 3‐21 ) have been prepared via the reaction of the coumarin‐3‐carbonyl chloride ( 1 ) with a number of nucleophiles. Novel double‐headed coumarin‐3N‐carboxamides ( 26‐33 ) were also produced using the same method. The Pechmann‐Duisberg reaction was applied to prepare new benzo[f]‐ benzo[h]coumarins and 4‐(chloromethyl)‐pyrano[3,2‐c]coumarin‐2‐one ( 36‐42 ). The reaction of 1‐chloromethylbenzo[f]coumarins ( 36 ) with cyanide anion under different reaction conditions was also investigated in order to assess its suitability for nucleophilic substitution reactions as well as ring transformation products ( 43‐49 ). Synthesis of 1‐((benzo[d]thiazol‐2‐yl)methyl)‐9‐hydroxybenzo[ f ]coumarin ( 50 ) represented the first example of methylene bridge‐head heterocyclecontaining benzo[f]coumarin. Some of the newly prepared coumarins exhibited anti‐bacterial activity against Gram Positive and Gram negative bacteria. Compound 36d was found to be active against all the screened bacteria. Photophysical studies were performed on selected fluorescent benzo[f]‐ and benzo[h]coumarin and the quantum yields were also calculated. All new compounds were characterized by IR, MS, ¹H and ¹³C NMR, as well as elemental analysis.     

Synthesis and antibacterial activities of pleuromutilin derivatives

Six new pleuromutilin derivatives were designed and synthesized, confirmed by MS, IR and 1H NMR techniques. And the antibacterial activities were primarily evaluated in vitro. The results indicated that most of the derivatives showed more potent activities against corresponding bacterial strains than that of pleuromutilin. Especially, compounds 4d and 5b had obvious activities against salmonella compared with pleuromutifin.     

酰胺类喹唑啉酮衍生物的合成及抗菌活性

本文设计并合成了23个含酰胺结构单元的新型喹唑啉酮类化合物,经1 H NMR、13 C NMR和HRMS确证结构.在100μg·mL-1和50μg·mL-1浓度下,评价了它们对水稻白叶枯病菌、猕猴桃溃疡病菌和柑橘溃疡病菌的抑菌活性.结果表明,化合物对柑橘溃疡病菌有较强的抑制活性,并测定了6个化合物对柑橘溃疡病菌的EC5...     

Synthesis of novel azo Schiff bases and their antibacterial and antifungal activities

Ten new azo Schiff bases 5a-h and 7a-b were prepared in excellent yields via the condensation of different aromatic amines and a new azoaldehyde, 2-hydroxy-3- methoxy-5-(4-methoxyphenylazo)benzaldehyde (4) by two different methods. All new compounds were tested against five microorganisms: Staphylococcus aureus (Gram positive and methicillin resistant), Bacillus subtilis (Gram positive), Kelebsiella pneumonia, Pseudomonas aeruginosa and Escherichia coli (all Gram negative). Compounds 4, 5a, 5c, 5d and 5g were moderately active against Staphylococcus aureus and Bacillus subtilis. Compound 7b was highly active against Bacillus subtilis and moderately active against Staphylococcus aureus. Other compounds were inactive against these strains of bacteria. The antifungal activities of these compounds were also tested against eight different fungal species. None of them were active against the fungi species tested.     

Synthesis and biological activities of thio-triazole derivatives as novel potential antibacterial and antifungal agents

A series of novel thio-triazole derivatives including thiols, thioethers and thiones as well as some corresponding triazolium compounds were conveniently and efficiently synthesized from commercially available halobenzyl halides and thiosemicarbazide. All the new compounds were characterized by 1 H NMR, 13 C NMR, FTIR, MS and HRMS spectra. Their antibacterial and antifungal activities in vitro were evaluated against four Gram-positive bacteria, four Gram-negative bacteria and two fungi by two-fold serial dilution technique. The preliminary bioassay indicated that some prepared triazoles exhibited effective antibacterial and antifungal activities. Especially, 3,4-dichlorobenzyl triazolethione and its triazolium derivatives displayed the most potent activities against all the tested strains.     

Synthesis of some new pyrimidine derivatives and evaluation of their anticancer and antibacterial activities

Starting from the reaction of ethyl cyanoacetate with thiourea and the appropriate aldehydes, a series of new pyrimidine derivatives were prepared. Ten selected pyrimidine derivatives were subjected to a screening system for the investigation of their antitumor potency against liver (HEPG2) cell line. The antitumor activity results indicated that most of the selected pyrimidine derivatives showed moderate growth inhibition activity against the tested cell line, but with varying intensities in comparison to the known anticancer drugs: 5-fluorouracil and doxorubicin. Some of the synthesized compounds were also tested for their antimicrobial activity against bacteria as well as fungal isolates.     

Synthesis of 2‐aryl and coumarin substituted benzothiazole derivatives

A facile and effective method for the synthesis of some benzothiazole derivatives is described. The method involves the action of aryl aldehyde and o‐aminothiophenol in acetic acid resulting into in situ formation of the thiol substituted Schiff's base and its cyclization to 2‐aryl benzothiazole upon prolonged heating.     

Synthesis and properties of coumarin derivatives and their terbium complexes

A series of coumarin derivatives obtained from salicylaldehyde and phenol were synthesized. Their corresponding terbium complexes were prepared and characterized by elemental analysis, EDTA titrations, molar conductivity, UV–vis spectra, IR spectra, and thermal analysis. The luminescent properties and electrochemical properties of the terbium complexes were also investigated. The results showed that all the terbium complexes exhibited characteristic emissions of terbium ions. The introduction of electron-donating groups can improve the luminescent properties, decrease the HOMO and LUMO energy levels of the terbium complex, while electron-withdrawing groups can weaken the luminescent properties, and increase the HOMO and LUMO energy levels of terbium complex.     

Synthesis and reactivity of substituted alkoxymethylphosphonites and their derivatives

Alkoxy‐substituted methylphosphonites and their derivatives are prepared using an organomagnesium method of synthesizing the organophosphorus compounds and alkoxymethylation of various PH acids and their derivatives. Also, certain properties of these promising compounds as important precursors of new functionalized organophosphorue compounds with alkoxymethyl fragments are presented. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:281–289, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21015     

Synthesis and antitubercular activity of substituted novel pyrazoline derivatives

A series of 2-2-methoxy-4-[5-(substituted phenyl)1-(4-pyridylcarbonyl)-4,5-dihydro-1H-3-pyrazolyl] phenoxyacetic acid were synthesized by the reaction between isoniazid (INH) and chalcones, and were tested for their antimycobacterial activity in vitro against Mycobacterium tuberculosis H37Rv and INH resistant M. tuberculosis using BACTEC-460 radiometric system and agar dilution method. Among the synthesized compounds, Compounds II 2-4-[5-(4-hydroxyphenyl)-1-(4-pyridylcarbonyl)-4,5-ihydro-1H-3-pyrazolyl]-2-methoxy phenoxy acetic acid was found to be most active agent against M. tuberculosis H37Rv (MTB) and INH resistant M. tuberculosis (INHR-MTB), with minimum inhibitory concentration of 0.12 microM, when compared to INH 5.6-fold more active against MTB and 78-fold more active against INHR-MTB, respectively.     

Synthesis,spectroscopic and antibacterial investigations of new hydroxy ethers and heterocyclic coumarin derivatives

The reactions between oligoethylene glycol diglycidyl ethers 2a‐c with both 7‐hydroxy‐4‐methyl‐2H‐chromen‐2‐one and 4‐hydroxy‐2H‐chromen‐2‐one lead to new hydroxy ethers 3 and 4 containing coumarin moieties in good yield. The synthesis of 3‐(3‐(dimethylamino)acryloyl)‐4‐hydroxy‐2H‐chromen‐2‐one 5 and new heterocyclic compounds 4‐hydroxy‐3‐(1H‐pyrazol‐3‐yl)‐2H‐chromen‐2‐one 6a , 4‐hydroxy‐3‐(1‐phenylpyrazol‐3‐yl)‐2H‐chromen‐2‐one 6b and 4‐hydroxy‐3‐(isoxazol‐3‐yl)‐2H‐chromen‐2‐one 6c is also described. All compounds were characterized by ¹H NMR, ¹³C{¹H} NMR, 2D‐¹H‐¹³C HMBC, 2D‐¹H NOESY NMR, IR, and MS spectroscopy. Additionally, the antibacterial activity of the new products containing coumarin moiety was evaluated. This activity is clearly dependent on the chemical structure of compounds.