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211.
Wanda Mczka Anna Duda-Madej Aleksandra Grny Magorzata Grabarczyk Katarzyna Wiska 《Molecules (Basel, Switzerland)》2021,26(16)
One of the primary reasons for the search for new antimicrobial agents is the increasing and spreading resistance of microorganisms to previously used drugs. This is particularly important in the case of rapidly progressing infections that require the rapid administration of an appropriately selected antibiotic. However, along with the administration of antibiotics, complications in the disease-weakened body may arise in the form of systemic mycoses, viral infections, and protozoan infections. Therefore, there is an increasing interest among researchers focusing on the use of naturally occurring terpenic compounds in stand-alone or combined therapies with antibiotics. In this publication, the aim of our work is to present the results of a literature review on the antimicrobial activity of eucalyptol. 相似文献
212.
水杨醛双缩二氨基硫脲二丁基锡配合物的合成及杀菌活性研究 总被引:1,自引:0,他引:1
利用1,5-水杨醛双缩二氨基硫脲席夫碱与二丁基氧化锡为原料,在苯-甲苯混合溶剂中回流反应合成了有机锡席夫碱配合物,用元素分析、红外光谱、核磁共振谱对目标化合物结构进行了结构表征,并用X-射线单晶衍射对其结构进行了确证.晶体结构分析表明,标题配合物的晶体属三斜晶系,P-1空间群,每个独立单元中含有两个分子结构单元,晶胞参数:a=1.29705(6)nm,b=1.36654(7)nm,c=1.68517(8)nm,α=72.059(1)o,β=87.339(1)o,γ=63.435(1)o,V=2.5270(2)nm3,Z=4,Dcalc =1.433 g/cm3,μ=1.119 mm-1,F(000)=1112,R1=0.0563,wR2=0.1530.分子间经典的N-H...N氢键使分子相互缔合形成二聚体,后者再通过范德华作用力结合堆积形成完全的晶体结构.杀菌活性测定结果表明,标题化合物及其类似物的杀菌活性具有较大的选择性,对苏云金杆菌(B.thuringiensis)和枯草杆菌(B.Subtilis)的杀菌能力较高,而对大肠杆菌(E.Coli)和金黄色葡萄球菌(S.Aureus)的杀菌能力较低. 相似文献
213.
The essential oil of the leaves of Cupressus sempervirens L. was isolated by hydrodistillation and tested against gram positive and gram negative bacteria, showing remarkable antimicrobial
activity against Bacillus subtilis with minimum inhibitory concentration (MIC) 75%. The antiviral activity of the essential oil was tested against Herpes simplex
virus type 1 (HSV-1), showing antiviral activity with virucidal percentages of 68.0% and 53.2% at concentrations of 1:32 and
1:64, respectively. We firstly reported the isolation of two epi-betulin esters of fatty acids from the CHCl3 fraction of Cupressus sempervirens L. leaves, which were isolated and purified using HPLC, and identified using PMR and MS. The CHCl3 fraction showed significant cytotoxicity against HeLa cells.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 265–268, May–June, 2009. 相似文献
214.
215.
在微波辅助下,1,3-二甲基-5-醛基巴比妥酸与芳氧基/芳胺基乙酰肼及含氮杂环乙酰肼缩合制备新型酰腙化合物,并对其抑菌活性进行评价的研究。 新化合物的结构经过元素分析、红外光谱、核磁共振谱、质谱和X射线单晶衍射等技术手段确认。 体外的抑菌活性实验显示,部分目标化合物呈现出优于环丙沙星的抑菌活性。 经过构效关系分析表明,当芳基为含氮杂环时,所形成的化合物抗菌活性与芳基为苯环时相比明显较强,抑菌活性最强的酰腙化合物2t对金黄色葡萄球菌的最小抑菌浓度(MIC)值为0.8 g/L,对大肠杆菌的最小抑菌浓度(MIC)值为1.6 g/L。 相似文献
216.
Ziya Erdem Koc 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(2):111-115
During the last few years, the potential of s-triazine derivatives in agrochemical and medicinal properties have been subjected to investigation. s-Triazine derivatives have received great attention due to their significant antimicrobial, antibacterial, antifungal, anti-HIV, anticancer, and a wide array of other biological activities. The present study reported a method for achieving Dipodal systems formed by reaction 2,4,6-trichloro-1,3,5-triazine and 4-hydroxybenzaldehyde, 2-aminophenol. Herein, we reported the synthesis of a dialdehyde and its Schiff base as a new template. The reaction of cyanuric chloride with 1 equiv. methanol and 2 equiv. of p-hydroxybenzaldehyde gave the desired dialdehyde. The dialdehyde was then reacted with 2-aminophenolto afford the corresponding multidirectional oxy-Schiff base triazines. The structures of the compounds were identified by FT-IR,1H-NMR and elemental analysis. Their antimicrobial activities were performed by using the broth microdilution method in DMSO: Phosphate Buffered Saline (PBS) against eight bacteria strain and one yeast strain. The results of the test were compared with gentamicin. It has been determined that 2,4-Bis(2-hydroxyphenylimino-4'-formylphenoxy)-6-methoxy-1,3,5-triazine (3) (2DP2AF) and 2-(2-hydroxyphenylimino-4'-formylphenoxy)-4-(4'-formylphenoxy)-6-methoxy-1,3,5-triazine (2) (1DP2AF) have significant antibacterial and antifungal activity against Enterococcus faecalis and Candida albicans and these effects were close to the control antibiotic used. Ent. faecalis was the most sensitive strain against both two tested chemicals. It was determined that our chemicals have similar antifungal capacity when compared to gentamicin. 相似文献
217.
Katherine A. Gibney Iva Sovadinova Analette I. Lopez Michael Urban Zachary Ridgway Gregory A. Caputo Kenichi Kuroda 《Macromolecular bioscience》2012,12(9):1279-1289
We report the structure–activity relationship in the antimicrobial activity of linear and branched poly(ethylene imine)s (L‐ and B‐PEIs) with a range of molecular weights (MWs) (500–12 000). Both L‐ and B‐PEIs displayed enhanced activity against Staphylococcus aureus over Escherichia coli. Both B‐ and L‐PEIs did not cause any significant permeabilization of E. coli cytoplasmic membrane. L‐PEIs induced depolarization of S. aureus membrane although B‐PEIs did not. The low MW B‐PEIs caused little or no hemolysis while L‐PEIs are hemolytic. The low MW B‐PEIs are less cytotoxic to human HEp‐2 cells than other PEIs. However, they induced significant cell viability reduction after 24 h incubation. The results presented here highlight the interplay between polymer size and structure on activity.
218.
以苯氧乙酸(Hpa)、对硝基苯氧乙酸(Hpnpa)和对甲基苯氧乙酸(Hpmpa)为原料,分别与2-氨基苯并噻唑(aben)和乙酸铜反应,合成了3种铜配合物[Cu(pa)2(aben)2](1),[Cu2(pnpa)4(aben)2](2)和[Cu(pmpa)2(aben)2].[Cu2(pmpa)4(aben)2](3),并通过元素分析、红外光谱和单晶X-射线衍射对其结构进行了表征。结果表明,3种配合物具有不同的配位模式,配合物1的中心Cu(Ⅱ)分别与2个羧基氧原子和2个噻唑环上的氮原子配位;配合物2的2个Cu(Ⅱ)则分别都与来自4个不同配体的羧基氧原子和1个噻唑环上的氮原子配位,从而在分子中形成了2个近乎垂直的八元环;配合物3为混配型化合物,1个Cu(Ⅱ)的配位数为4,另外2个Cu(Ⅱ)的配位数为5,参与配位的配体原子分别与配合物1和2相同。最低抑菌浓度的测定结果表明,3种配合物对真菌都表现出良好的抑制作用,且由于苯氧乙酸配体中取代基种类的不同,而使得配合物的抗菌效果出现明显的不同。 相似文献
219.
220.
Malgorzata Frik Dr. Josefina Jiménez Ismael Gracia Prof. Larry R. Falvello Sarya Abi‐Habib Karina Suriel Prof. Theodore R. Muth Prof. María Contel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(12):3659-3674
The reaction of new dinuclear gold(I) organometallic complexes containing mesityl ligands and bridging bidentate phosphanes [Au2(mes)2(μ‐LL)] (LL=dppe: 1,2‐bis(diphenylphosphano)ethane 1 a , and water‐soluble dppy: 1,2‐bis(di‐3‐pyridylphosphano)ethane 1 b ) with Ag+ and Cu+ lead to the formation of a family of heterometallic clusters with mesityl bridging ligands of the general formula [Au2M(μ‐mes)2(μ‐LL)][A] (M=Ag, A=ClO4?, LL=dppe 2 a , dppy 2 b ; M=Ag, A=SO3CF3?, LL=dppe 3 a , dppy 3 b ; M=Cu, A=PF6?, LL=dppe 4 a , dppy 4 b ). The new compounds were characterized by different spectroscopic techniques and mass spectrometry The crystal structures of [Au2(mes)2(μ‐dppy)] ( 1 b ) and [Au2Ag(μ‐mes)2(μ‐dppe)][SO3CF3] ( 3 a ) were determined by a single‐crystal X‐ray diffraction study. 3 a in solid state is not a cyclic trinuclear Au2Ag derivative but it gives an open polymeric structure instead, with the {Au2(μ‐dppe)} fragments “linked” by {Ag(μ‐mes)2} units. The very short distances of 2.7559(6) Å (Au? Ag) and 2.9229(8) Å (Au? Au) are indicative of gold–silver (metallophilic) and aurophilic interactions. A systematic study of their luminescence properties revealed that all compounds are brightly luminescent in solid state, at room temperature (RT) and at 77 K, or in frozen DMSO solutions with lifetimes in the microsecond range and probably due to the self‐aggregation of [Au2M(μ‐mes)2(μ‐LL)]+ units (M=Ag or Cu; LL=dppe or dppy) into an extended chain structure, through Au? Au and/or Au? M metallophilic interactions, as that observed for 3 a . In solid state the heterometallic Au2M complexes with dppe ( 2 a – 4 a ) show a shift of emission maxima (from ca. 430 to the range of 520‐540 nm) as compared to the parent dinuclear organometallic product 1 a while the complexes with dppy ( 2 b–4 b ) display a more moderate shift (505 for 1 b to a max of 563 nm for 4 b ). More importantly, compound [Au2Ag(μ‐mes)2(μ‐dppy)]ClO4 ( 2 b ) resulted luminescent in diluted DMSO solution at room temperature. Previously reported compound [Au2Cl2(μ‐LL)] (LL dppy 5 b ) was also studied for comparative purposes. The antimicrobial activity of 1–5 and Ag[A] (A=ClO4?, SO3CF3?) against Gram‐positive and Gram‐negative bacteria and yeast was evaluated. Most tested compounds displayed moderate to high antibacterial activity while heteronuclear Au2M derivatives with dppe ( 2 a – 4 a ) were the more active (minimum inhibitory concentration 10 to 1 μg mL?1). Compounds containing silver were ten times more active to Gram‐negative bacteria than the parent dinuclear compound 1 a or silver salts. Au2Ag compounds with dppy ( 2 b , 3 b ) were also potent against fungi. 相似文献