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排序方式: 共有118条查询结果,搜索用时 110 毫秒
1.
P. R. Latthe P. S. Shinge Bharati V. Badami P. B. Patil S. N. Holihosur 《Journal of Chemical Sciences》2006,118(3):249-256
3-[4-(Azidocarbonyl)]phenylsydnone (2) obtained from 3-(4-hydrazinocarbonyl) phenylsydnone (1) on Curtius rearrangement with alcohols, water and amines afforded the corresponding carbamates (3a-h), 4,4′-(sydnone-3-yl) diphenyl urea (4) and 4-(heterocyclyl)phenyl ureas (5a-l). Compounds (5a-l) on one-pot ring conversion yielded the 1,3,4-oxadiazolin-2-one derivatives (6a-l), which on reaction with N2H4 gave the 4-amino-1,2,4-triazolin-3-ones (7a-l). All these compounds exhibited moderate antimicrobial activity against the few microbes tested. The carbamates have been
found to be more toxic against fourth instar larvae ofAedes aegypti, in particular, then-butyl derivative (3e). 相似文献
2.
Viscometric method has been used to study the interaction between the weak interacting systems such as benzene-CCl4-cyclohexane, toluene-CCl4-cyclohexane ando- xylene-CCl4-cyclohexane. The equilibrium constants and other thermodynamic parameters have been reported and compared with literature
data. 相似文献
3.
Anil P. Phadnis Bharati Sinha Bhagbat Nanda Sarita A. Patwardhan J. Venkatesh Rao Ravindra N. Sharma 《Monatshefte für Chemie / Chemical Monthly》1989,120(6-7):581-586
Summary A series of 8-proparglyoxy-3,7-dimethyl-2,6-octadienyl and 8-propargyloxy-3,7-dimethyl-6-octenyl ethers were prepared from 8-hydroxygeranyl and 8-hydroxycitronellyl ethers, respectively. Almost all compounds showed high toxicity toCulex quinquefaciatus larvae at 1 mgl–1 dose level.
Gegen Mücken aktive Produkte, 4. Mitt.: Synthese und biologische Aktivität von 8-Propargyloxy-3,7-dimethyl-2,6-octadienyl/6-octenyl-ethern
Zusammenfassung Eine Reihe von 8-Propargyloxy-3,7-dimethyl-2,6-octadienyl- und 8-propargyloxy-3,7-dimethyl-6-octenyl-ethern wurden aus 8-Hydroxygeranyl- bzw. 8-Hydroxycitronellyl-ethern hergestellt. Fast alle Verbindungen zeigten hoch Toxizität gegenüber Larven vonCulex quinquefaciatus in einer Dosierung von 1 mgl–1.相似文献
4.
D. Minić Nada Štrbac I. Mihajlović Ž. Živković 《Journal of Thermal Analysis and Calorimetry》2005,82(2):383-388
In this paper, the results of copper-lead matte investigations are presented. Investigated copper-lead matte is intermediate
product of the lead production in TREPCA-Zvečan. In the first part of the paper characterization of starting material is presented,
consisting of: chemical composition analysis (XRQ), scanning electron microscopy (SEM) and diffractometry (XRD). Thermal properties
of investigated matte were determined using differential thermal analysis (DTA) at characteristic temperatures. Using results
of induced analysis, mechanism of matte oxidation process was determined. In the second part of the paper kinetic parameters
describing oxidative roasting of copper-lead matte are presented. For activation energy calculations, non-isothermal methods
defined by Kissinger and Ozawa were used [1, 2]. Kinetic equation describing oxidation process was determined using Sharps
method of reduced half time of reaction [3]. 相似文献
5.
The mechanism of the addition of carbonyl compounds to digermenes was investigated by examining the reaction between tetramesityldigermene and two mechanistic probes: trans-2-phenylcyclopropane carbaldehyde and trans,trans-2-methoxy-3-phenylcyclopropane carbaldehyde. In each reaction, two diastereomers of the formal [2+2] cycloadduct between the aldehyde and the digermene were obtained. These findings, together with the results of a recent theoretical study, indicate that the addition of carbonyl compounds to digermenes proceeds via a mechanism involving a zwitterionic intermediate. 相似文献
6.
Bharati Banerjee D.K. Sinha 《International Journal of Mathematical Education in Science & Technology》2013,44(3):261-265
This paper, after analysing the meaning of ‘applied mathematics’, seeks to explore and set forth some broad outlines of the pedagogical implications of studies in the application of mathematics. 相似文献
7.
Virginie Blot Jean-François Brièr Marion Davoust Stéphanie Minière Vincent Reboul Patrick Metzner 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1171-1182
Abstract Our work on the thio-Claisen rearrangement mediated by an adjacent sulfinyl group is reviewed. The substrates could easily be prepared on a large scale from diacetone-D-glucose. The rearrangement was effected with a diastereoselectivity of 95:5, in favor of the (S,S) or the (R,R) isomer. An approach to natural bis(lactones) was investigated, using a halolactonization reaction and a second [3,3] sigmatropic shift, again mediated by the sulfinyl group. The second part deals with the catalytic enantioselective benzylidenation of aldehydes, mediated by chiral sulfur ylides. We have introduced simple C 2 symmetric thiolanes for that purpose. The procedure is very practical and enantiomeric excesses up to 96% have been reported for the model of stilbene oxide. A series of ferrocenyl sulfides with planar chirality has also been investigated, leading to unexpected diastereoselectivities and enantiomeric excesses up to 94%. 相似文献
8.
Ljubiša Balanović Dragana Živković Dragan Manasijević Duško Minić Bata Marjanović 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1431-1435
The results of calorimetric study and thermal analysis of binary Al–Sn system are presented in this paper. The Oelsen calorimetry was used in thermodynamic analysis. Following thermodynamic properties were determined at 727 °C: activities, activity coefficients, partial/integral molar Gibbs excess, and mixing energies. The energetics of mixing in liquid Al–Sn alloys has been analyzed through the study of concentration fluctuation in the long-wavelength limit. Thermal analysis of selected alloys in Al–Sn system was done using differential thermal analysis. Defined characteristic phase transition temperatures were used for comparison with calculated phase diagram of investigated system. Good agreement with available literature data was obtained. Structural analysis of selected alloys was done using optic microscopy. 相似文献
9.
A new phenanthroindolizidine alkaloid, 3-O-demethyl tylophorinidine (VI), was isolated from the aerial (leaves and stem) parts of Tylophora indica and characterized using different spectral techniques. Gel chromatography and reverse phase preparative HPLC were used for sample purification. The new alkaloid, VI, was screened for anticancer activity against a panel of different cancer cell lines and it showed significant anticancer activity with IC50 value in the range of 0.89?C1.40 ??M. 相似文献