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91.
The first total synthesis of triumfettamide (1) is described. The asymmetric syntheses of two highly functionalized units—α-hydroxylated C17 monounsaturated fatty acid unit (2) and C26 phytosphingosine (3) have been accomplished involving Sharpless asymmetric dihydroxylation, Sharpless kinetic resolution, regioselective epoxide opening, regioselective DIBAL-H reduction of acetal, Wittig olefination as the key steps. Finally N-acylation of phytosphingosine 3 with (2R,6Z)-2-hydroxy-6-heptadecenoic acid 2 followed by DDQ deprotection of PMB, provided target compound 1.  相似文献   
92.
93.
The novel 2-(1H)-pyridone, the lead compound of the pyridone derivative 1, reacted with an electrophilic reagent (ethyl chloroacetate) to give the corresponding ester 2. Condensation of compound 2 with thiosemicarbazide and/or hydrazine hydrate afforded the mercaptotriazole and the corresponding acetic acid hydrazide derivatives 3 and 4, respectively. The latter compound reacted with ethyl acetoacetate, ethyl cyanoacetate, and maleic anhydride to give compounds 5, 6, and 7, respectively. Alkylation of compound 3 with methyl iodide or chloroacetic acid afforded methylsulfanyltriazole and thiazolotriazole derivatives 8 and 9, respectively. Compound 8 reacted with glycine to afford the imidazotriazole derivative 10. Both compounds 9 and 10 reacted with glucose and benzaldehyde to give compounds 11, 12, 13, and 14, respectively. Some of the prepared products were selected and subjected to screening for their antioxidant activity.  相似文献   
94.
Ring opening of 4-aryl-2-phenyloxazol-5-one 1 with 2-aminobenzoic acid in acetic acid and n-butanol gave compounds 2 and 3, respectively. The 4H-3,1-benzoxazin-4-one derivative 4 was synthesized by refluxing of compound 2 in acetic anhydride. Then it reacted with different nitrogen nucleophiles such as hydrazine hydrate, phenylhydrazine, cyclohexylamine, piperidine, ethylenediamine, ethanolamine, semicarbazide hydrochloride, cyanoacetohydrazide and methyl glycinate hydrochloride to give compounds 5–14 in order to study the behavior of these nucleophilic reagents on the performed ring system. All the structures of the newly prepared compounds were characterized by their IR, 1H-, 13C-NMR and MS spectral data. Some of the synthesized compounds were screened for their antimicrobial and antioxidant activities. Compound 5 showed remarkable activity upon this screening.  相似文献   
95.
Amino acids based surfactants belong to the class of surfactants with high biodegradability, low toxicity and excellent surface active properties. They possess excellent emulsifying, detergency properties and form fine lather. These surfactants are environment friendly, mild to skin and eyes, and have hard water tolerance. This article reviews types, synthesis, various surface properties such as cmc (critical micelle concentration), surface tension, phase behavior, Krafft temperature, and interfacial adsorption of these surfactants. The biological properties such as antimicrobial activity, aquatic toxicity, biodegradability and hemolytic activity have also been focused. The various applications of amino acid based surfactants in the area of life sciences such as gene transfection, formation of liposomes, and drug delivery systems have also been reviewed.  相似文献   
96.
A novel perfluoroalkyl-containing quaternary ammonium salt 5 was designed and synthesized. Consequently, the antimicrobial activities of compound 5 were measured with Escherichia coli 8099 as a Gram-negative strain and Staphylococcus aureus ATCC 6538 as a Gram-positive strain. Both the minimum inhibitory concentration (MIC, the lowest concentration of compound 5 that inhibits microbial growth) values of quaternary ammonium salt 5 against Escherichia coli 8099 and Staphylococcus aureus ATCC 6538 were 7.8 μg/ml.  相似文献   
97.
《印度化学会志》2023,100(1):100824
The compound (E)-4-((4-hydroxy-3-methoxy-5-nitrobenzylidene) amino)-N-(thiazole-2-yl) benzene sulfonamide (5NVTH) was synthesized and characterized by the Infrared, UV-Visible, and NMR analysis. The compound theoretical study was done by using DFT. The compound molecular structure and geometry were defined using DFT. Topological studies, like ELF, LOL, ALIE, and RDG studies, were done with the Multiwfn-3.8 to find the main binding areas and weak interactions in the molecule. Using the IEFPCM solvation model was used to study the calculated UV-Visible spectrum. The HOMO-LUMO, MEP, and NBO properties were carried out in the gas phase. The NBO calculations are used to study how charges move between and within the molecule and the stability of this molecule. A pharmacological analysis is done using an online tool like Swiss-ADME, to see if the molecule could be a potential drug candidate; this evaluation looks at the drug-likeness, ADME, and eco-friendly toxicity properties of the 5NVTH molecule. Auto-dock suite is used for molecular docking study and discovery studio is used for analyzing the docking results. Antimicrobial activity studies indicate the compound Klebsiella pneumonia and Candida albicans have good antibacterial and antifungal activity compared to positive control and other microorganisms.  相似文献   
98.
Infections can lead to severe health issues, even death. Surfaces, such as those of biomedical devices, implants, textiles, tables and doorknobs, play a crucial role as carriers for pathogens to migrate, attach and proliferate. Implementing surfaces with antimicrobial properties offers a reliable and long-lasting approach to combat surface transmission of germs, minimize microbial colonization, and reduce infections. In this review, we present recent advancements in antimicrobial surfaces, categorized into four groups based on their action mechanisms: antifouling, bactericidal, antifouling and bactericidal, and dynamic or stimuli-responsive surfaces. The work highlights the fabrication processes and properties of each category, along with discussing their structure-performance relationships. Special attention is given to various anchoring strategies involving tunable molecular interactions. The review also introduces relevant biomedical applications.  相似文献   
99.
《印度化学会志》2023,100(4):100973
The antimicrobial resistance and excessive use of modern drugs has hampered the treatment of infectious disease. Therefore, the development of new antibiotics with very good efficacy and lesser side effects is the focused area of medicinal chemists. In the present work, the design and copper (I) catalyzed click synthesis of some amide linked binol based 1,4-disubstituted 1,2,3-bistriazole hybrids from bisalkyne precursor is reported along with characterization of the newly synthesized bistriazoles with the support of IR, NMR and HRMS spectral techniques. The in vitro antimicrobial screening of these bistriazoles against selected bacterial (S. aureus, B. subtilis, and E. coli) and fungal (A. niger and C. albicans) strains signifies the importance of amide and triazole moiety in the final derivatives. The in silico docking studies further supports the antimicrobial results through various binding interactions with binding energies of compound 6f (1KZN: 9.7 kcal/mol) and 6h (4WMZ: 13,3 kcal/mol).  相似文献   
100.
彭涛  吴文能 《化学通报》2021,84(6):604-609
以2-胺基苯甲酸为原料,通过环化、缩合、肼解、环化、硫醚化和氧化等步骤,合成了10个含喹唑啉酮取代1,3,4-噁二唑(噻二唑)化合物。通过1H NMR、13C NMR、MS 和元素分析进行确证其结构。初步抑菌活性测试表明,化合物浓度在50 μg/mL时,对葡萄座腔菌(Botryosphaeria dothidea)、拟茎点霉菌(Phomopsis sp.)和灰霉菌(B. cinerea)具有中等抑制活性。另外,目标化合物对猕猴桃溃疡病(Pseudomonas syringae pv. actinidia)均具有一定的抑制活性,其中化合物6a和6b对猕猴桃溃疡病的EC50值为11.7 μg/mL和20.5 μg/mL,优于对照药剂叶枯唑(24.5 μg/mL)。这类化合物具有较好抗菌的生物活性,在此基础上进行结构优化,有望发现较高活性化合物。  相似文献   
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