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101.
S.A. Sadaphal P.D. Ghogare S.G. Gupta B.B. Shingate M.S. Shingare 《Arabian Journal of Chemistry》2012,5(2):257-261
Potential biologically active derivatives of arylhydrazotriazole (3a–l) were prepared by the condensation reaction of diazonium salts using various aromatic amines (1a–l) and 1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl) ethanones (2). The synthesized products were obtained in 75–85% yield. All the synthesized products were having good-excellent antifungal activity as compared with standard (Fluconazole and Ketoconazole) drugs. 相似文献
102.
Gerhard Friedrich Thorsten Rose Alexander Wawkuschewski Sabine Kafert-Kasting Britta Laube Lubomir Arseniev Klaus Rissler 《Chromatographia》2008,67(1-2):31-39
In a recently published paper development of a sensitive automated “on-line” solid-phase extraction (SPE)/RP-HPLC assay for
6β-hydroxytestosterone (6β-OHT) with corticosterone as the internal standard (IS) was reported and its potential for quantification
of various testosterone metabolites in culture media reflecting metabolic activity of cultured human and animal hepatocytes
demonstrated [1]. In this following contribution the technique has been extended to determination of another five testosterone metabolites
in cultured rat hepatocytes using an identical “on-line” SPE/RP-HPLC procedure and detection by tandem MS-MS with an atmospheric
pressure chemical ionization (APCI) source in the selected reaction monitoring (SRM) mode as that described in [1]. All six testosterone metabolites, namely 2α-OHT, 2β-OHT, 6α-OHT, 6β-OHT, 7α-OHT and 16α-OHT, could be sufficiently separated
from each other and thus an unequivocal assignment to the individual structures was achieved. Validation data are presented
specifying the limits of quantitation as well as the mean values of the coefficients of variation (CV) for the target analytes
and the accuracy obtained at five different days. Regio- and stereoselective testosterone hydroxylation by rat hepatocytes
was measured in a long-term culture system with and without exposure to rifampicin as an inducer of liver CYP 3A4 activity.
In addition, testosterone hydroxylation was analyzed in cultures of cryopreserved hepatocytes that had been stored at −196 °C.
The rat hepatocytes were cultured after thawing for up to 11 days and induction of testosterone hydroxylase activity could
be demonstrated in cultures which underwent a new cryopreservation protocol.
This paper is dedicated to Professor Hinrich Cramer on the occasion of his 75th birthday. 相似文献
103.
A series of novel derivatives of 4, 5, 6, 7-tetrahydrothieno [3,2-c] pyridine were synthesized and structurally characterized by 1H NMR and MS. Their in vivo anti-platelet aggregation activities were evaluated. A 3D-QSAR was performed using the CoMFA and the CoMSIA. This model provided useful guidelines for novel anti-platelet thienopyridines design. 相似文献
104.
It is common to schedule project activities first, then the utilization of equipment and its operating crew is planned based on such schedule. Real world experiences indicate that activity scheduling can be heavily impacted by the resources needed. In particular, if a project requires highly specialized and expensive equipment type, then one needs to take into account the schedule and cost of such resources in developing the project schedule. 相似文献
105.
Junhua Xiao Gu Yuarf Weiqiang Huang John H. K. Lum K‐L Daniel Lee Albert S. C. Chan 《中国化学会会志》2001,48(5):929-932
Two nitrated analogs of distamycin were synthesized by a novel haloform reaction and the DCC/HOBT coupling reaction in a convenient and effective way with out amino group protection. Our results have demonstrated that these polyamides show DNA cleaving activity under long UV (LUV 365 nm) irradiation. Furthermore, it is an unexpected discovery that these analogs can prevent DNA dam age under short UV (SUV 302 nm). 相似文献
106.
Bhupendra Chudasama Anjana K. ValaNidhi Andhariya R.V. UpadhyayR.V. Mehta 《Journal of magnetism and magnetic materials》2011,323(10):1233-1237
In recent years, rapid increase has been observed in the population of microbes that are resistant to conventionally used antibiotics. Antifungal drug therapy is no exception and now resistance to many of the antifungal agents in use has emerged. Therefore, there is an inevitable and urgent medical need for antibiotics with novel antimicrobial mechanisms. Aspergillus glaucus is the potential cause of fatal brain infections and hypersensitivity pneumonitis in immunocompromised patients and leads to death despite aggressive multidrug antifungal therapy. In the present article, we describe the antifungal activity of multifunctional core-shell Fe3O4-Ag nanocolloids against A. glaucus isolates. Controlled experiments are also carried out with Ag nanocolloids in order to understand the role of core (Fe3O4) in the antifungal action. The minimum inhibitory concentration (MIC) of nanocolloids is determined by the micro-dilution method. MIC of A. glaucus is 2000 μg/mL. The result is quite promising and requires further investigations in order to develop a treatment methodology against this death causing fungus in immunocompromised patients. 相似文献
107.
108.
Awatef Ayadi Amani Jaafar Adeline Fix-Tailler Ghassan Ibrahim Gérald Larcher Abdelkrim El-Ghayoury 《Tetrahedron》2017,73(25):3554-3563
The synthesis of two tetrathiafulvalene-appended pyridinehydrazone pyrimidine ligands, namely (Z)-4-(2-((5-([2,2′-bi(1,3-dithiolylidene)]-4-yl)pyridin-2-yl)methylene) hydrazinyl)-6-chloropyrimidine L1 and (Z)-4-(2-((6-([2,2′-bi(1,3-dithiolylidene)]-4-yl)pyridin-2-yl)methylene) hydrazinyl)-6-chloropyrimidine L2 is described. Ligand L1 was reacted with cobalt(II) to yield a cationic metal complex [Co(L1)2] while ligand L2 was reacted with zinc(II) to afford a neutral metal complex [ZnL2Cl2]. The crystal structure analysis of [Co(L1)2] indicate that Co(II) ion is coordinated by six nitrogen atoms from two perpendicular ligands while in [ZnL2Cl2], Zn(II) is coordinated by two chlorine atoms and three nitrogen atoms. The electrochemical behavior indicate that ligands L1 and L2 and the zinc(II) complex are suitable fort the preparation of crystalline radical cation salts. Finally the determination of MIC80 values against C. albicans, C. glabrata, C. parapsilosis, C. krusei and E. dermatitidis revealed that the cobalt(II) metal complex [Co(L1)2] is active against all the studied fungi. 相似文献
109.
110.
在超声辐射和哌啶催化反应条件下,1,3-二氢吲哚-2-酮(1)与芳香醛2a~2m发生Knoevenagel缩合反应,合成了一系列3-芳亚甲基吲哚-2-酮衍生物3a~3m。该方法具有产率高、反应时间短、后处理简单和环境友好等优点,产物通过~1H NMR、~(13)C NMR和HRMS手段进行结构表征,并通过核磁2D NOESY确定了所有化合物几何构型。初步抑菌活性测试结果表明,化合物3d对革兰氏阳性菌具有较好的抑制作用,最小抑菌浓度(MIC)为15.6μg/m L,化合物3f、3g、3h和3k对油菜菌核病菌表现出良好的抑制活性,MIC为62.5μg/m L,与阳性对照多菌灵相当。此外,对此类化合物的构效关系进行了讨论。 相似文献