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1.
The eco-friendly synthesis, spectroscopic (IR, MS, 1H and 13C NMR) study and biological (cytostatic, antiviral) activity of sodium and potassium benzeneazophosphonate complexes, obtained by reaction in the solid state under microwave irradiation of the alkali salts of ethyl [α-(4-benzeneazoanilino)-N-benzyl]phosphonic acid and [α-(4-benzeneazoanilino)-N-4-methoxybenzyl]phosphonic acid with crown ethers containing 18-membered (dibenzo-18-crown-6 and bis(4′-di-tert-butylbenzo)-18-crown-6), 24-membered (dibenzo-24-crown-8) and 30-membered (dibenzo-30-crown-10) macrocyclic rings, have been described. The simple work-up solvent free reaction is an efficient green procedure for the formation of mononuclear crown ether complexes in which the sodium/potassium ion is bound to oxygen atoms of the macrocycle and the phosphonic acid oxygen. The free crown ethers, alkali benzeneazophosphonate salts and their complexes were evaluated for their cytostatic activity in vitro against murine leukemia L1210, murine mammary carcinoma FM3A and human T-lymphocyte CEM and MT-4 cell lines, as well as for their antiviral activity against a wide variety of DNA and RNA viruses. The investigated compounds showed no specific antiviral activity, whereas all the free crown ethers and their complexes demonstrated cytostatic activity, which was especially pronounced in the case of bis(4′-di-tert-butylbenzo)-18-crown-6 and its complexes.  相似文献   
2.
A conceptually new Diels-Alder approach, involving a diene moiety grafted on a preformed epoxyquinone platform and a 4-hydroxy-indenone as the dienophile, delivers the pentacyclic framework of fluostatin C in one key step.  相似文献   
3.
Osawa T  Naito T  Suzuki N  Imai K  Nakanishi K  Kawakami J 《Talanta》2011,85(3):1614-1620
Contamination of the exterior surface of vials of cytostatic drugs by the drugs themselves is a potential hazard to human health. This study developed a validated method using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for the determination of contamination of the exteriors of vials of cisplatin and carboplatin. Large Alpha® sampling swabs were employed to wipe the vial exterior. Cisplatin or carboplatin and gold(III) as an internal standard were derivatized by N,N-diethyldithiocarbamate (DDTC). Pt(DDTC)3+ and Au(DDTC)2+ were monitored by the respective transitions of m/z 639.3-490.9 and 493.0-345.0, respectively. Each separation was completed within 9 min using a 3 μm particle ODS-column. Calibration curves for cisplatin and carboplatin were linear over concentration ranges of 30-10,000 and 30-30,000 pg vial−1, respectively. The accuracies and precisions were 96.1-102.5% and within 8.2% for intra-assay and 99.6-103.3% and within 7.6% for inter-assay, respectively. Their lower limit of quantification was 30 pg vial−1. Amounts of 0.17-17.0 ng vial−1 as cisplatin and 0.48-794 ng vial−1 as carboplatin were detected from the exterior surface of the vials. This validated method using LC-ESI-MS/MS for the determination of platinum anticancer drugs is helpful for monitoring contamination of the exterior surface of drug vials.  相似文献   
4.
In recent years, an increasing concern has risen about the presence of pharmaceuticals in the aquatic environment. Despite their toxicity, increasing consumption and release into the municipal sewage, only a few studies have been focused on cytostatic drugs, mainly due to the lack of methods for their simultaneous analysis. In this work, a method, based on solid-phase extraction prior to high-performance liquid chromatography-triple quadrupole mass spectrometry determination, was optimized and validated for the simultaneous determination of some (14) of the most widely used cytostatic drugs in river water, influent and effluent wastewater. Process efficiency was in the range between 41 and 99% in real samples, except for cytarabine (24%), docetaxel (17%) and methotrexate (30%), due to suppression effects; precision values were <11%, except for gemcitabine (up to 19%); and detection limits were in the range between 0.1 and 38 ng/L. Cytarabine, doxorubicin, etoposide, gemcitabine, iphosphamide and vinorelbine were found at concentration levels up to 14 ng/L in influent and effluent wastewater, showing an insignificant decrease during sewage treatment; cytarabine and gemcitabine were found in effluent wastewater and were also detected in river water associated with effluent discharges.  相似文献   
5.
For testing “univariate” binomial proportions, it has been proven that, under mild conditions, there exist group sequential designs which satisfy the pre-specified Type I error and power of the single-stage design while the sample size is bounded above by that of the single-stage design (Kepner and Chang, 2003). In this article, we extend this result and prove the existence of such group sequential designs for various decision rules in the space of bivariate binomial variables. We also demonstrate how to obtain the actual group sequential designs for detecting changes in bivariate binomial variables.  相似文献   
6.
Summary The three-dimensional structure of dolastatin-10, an extremely potent cytostatic and antineoplastic peptide extracted from the mollusc Dolabella auricularia, has not yet been fully characterized in an experimental way. By means of a systematic conformational search of the natural peptide and of two mutated analogs, carried out both in vacuo and in aqueous solution, the present work allows to obtain insights into the conformational preferences of this remarkable compound. In addition, the ability to form intra- and intermolecular H-bonds as a function both of the sequence and of the conformation is discussed. The search for the best molecular conformations has been carried out using a molecular mechanics approach, based on the CVFF potential. Dolastatin-10 contains some unusual amino acids for which no experimental structural data are available. In order to check the reliability of the CVFF potential in predicting structures of such nonconventional amino acids, geometry optimizations have been carried out using the ab initio Hartree-Fock procedure. The CVFF parameterization is found to be adequate also for nonconventional amino acids.  相似文献   
7.
3-(Fluoroacyloxy)quinoline-2,4(1H,3H)-diones react with triethyl phosphite to afford either the product of the Perkow reaction or the corresponding 4-ethoxyquinolin-2(1H)-one. In both reactions, the fluorocarboxylate anion acts as the leaving group. For the corresponding 3-(fluoroiodoacetoxy) derivative this observation precludes the application of the intramolecular Wittig-Horner synthesis to modify quinoline-2,4(1H,3H)-diones by the annulation of a fluorinated but-2-enolide moiety.  相似文献   
8.
(+)-12,15-Epoxylabda-8(17),12,14-trien-16-yl acetate has been isolated from the seed kernels of Turraeanthus africanus (Nelw. ex DC). The stereo structure was confirmed by 1D-and 2D-NMR spectroscopy. Cytostatic/cytotoxic test of (I) on the growth of cancer cells in vitro gave positive results. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 38–39, January–February, 2006.  相似文献   
9.
Tamoxifen and 5-fluorouracil are widely used in cancer therapy. They are highly toxic (teratogenic, mutagenic, etc.), as are most of the anticancer drugs. Two methods were set up to analyse these drugs in wastewaters to evaluate the potential for environmental contamination by cytostatic agents. Liquid–liquid extraction followed by purification on OASIS® MCX cartridge and gas chromatography with mass spectrometry detection (GC-MS) was used for the analysis of tamoxifen. 5-Fluorouracil was extracted with an ENV+?(Isolute) cartridge (solid-phase extraction), derivatized with pentafluorobenzyl bromide (PFBBr) and detected by GC-MS. Both methods showed good recoveries (>70%), repeatability (RSD<10%) and limits of detection (LOD 6–15?ng/L). Wastewaters from a residential area, a hospital, and sewage-treatment plants (STPs) were analysed using the analytical methods developed in this study. Tamoxifen was detected in wastewaters of the hospital, residential area, and influent of STPs, but not in treated wastewaters. 5-Fluorouracil in all wastewaters was below the LOD of the analytical method.  相似文献   
10.
A novel, two-step, facile route for the synthesis of pyrrolo[2,3-b]quinoxalines via 2,3-dioxopyrroles, enhanced by microwave irradiation, is presented. The newly synthesized 2,3-dioxo-5-halophenyl pyrrolo precursors 4ac as well as the non-aromatized ethyl 2-(4-halophenyl)-1-methyl-2,4-dihydro-1H-pyrrolo[2,3-b]quinoxaline-3-carboxylates 6ac and the aromatized ethyl 2-(4-halophenyl)-1-methyl-1H-pyrrolo[2,3-b]quinoxaline-3-carboxylates 7ac were evaluated for their antioxidant, cytostatic, and antiviral properties. Most of them proved to be potent hydroxyl radical scavengers and inhibited in vitro lipid peroxidation. The compounds showed moderate antiproliferative activity, while 6a inhibited vaccinia virus at an EC50 value of 2 μM, and 4c and 6c inhibited Sindbis virus at EC50 values of 4 μM.  相似文献   
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