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91.
Latif Kelebekli Baris Anil Suleyman Goksu Ertan Sahin 《Journal of the Iranian Chemical Society》2018,15(9):1969-1974
The first syntheses and characterizations of 6,7a-dichloro-3a-hydroxyoctahydro-1H-indene-2,5-diyl diacetates were successfully obtained starting from indan-2-ol. Epoxidation of 2 was carried out using mCPBA in methylene chloride followed by acetylation using acetyl chloride to furnish the diacetates. The structures of all synthesized compounds were characterized by spectroscopic methods. 相似文献
92.
We introduce and study relative Rickart objects and dual relative Rickart objects in abelian categories. We show how our theory may be employed in order to study relative regular objects and (dual) relative Baer objects in abelian categories. We also give applications to module and comodule categories. 相似文献
93.
Homobenzonorbornadiene and benzobarrelene were reacted with dimedone/acetylacetone and Mn(OAc)3 in the presence of Cu(OAc)2 in acetic acid. Mainly rearranged products having a [2.2.2]skeleton and the nonrearranged dihydrofuran derivatives were obtained. These observations clearly indicated that the second oxidation takes place before the cyclization reaction. Furthermore, intramolecular tandem oxidations were observed where unusually oxyl radicals attack the double bond to form the products. The mechanism of the formation of the products is discussed. 相似文献
94.
Seed oils of 15Sideritisspecies collected from different regions in Turkey(S. athoa, S. brevidens, S. caesarea, S. condensata, S. congesta, S. dichotoma, S. erythrantha var. cedretorum, S. germanicopolitana ssp. germanicopolitana, S. hololeuca, S. lanata, S. libanotica ssp. violascens, S. lycia, S. niveotomentosa, S. perfoliata, S. phrygia, S. pisidica)were obtained by a Soxhlet apparatus using hexane. The oil yields were found to be between 5.6-36.3%. Fatty acids in the oils were converted to methyl esters and their compositions were determined by GC/MS. The main fatty acid components of the oils from all the species are linoleic (45.4-64.0%), oleic (12.3-26.5%), 6-octadecynoic (4.5-26.8%), palmitic (0.3-9.4%), and linolenic (0.8-2.0%) acids. 相似文献
95.
96.
Mustafa Catir Murat Cakici Semistan Karabuga Sabri Ulukanli Ertan Şahin Hamdullah Kilic 《Tetrahedron: Asymmetry》2009,20(24):2845-2853
Optically active propargylic alcohols are important chiral-building blocks in asymmetric synthesis, while the asymmetric addition of a terminal alkyne to an aldehyde is one of the most important procedures to prepare these chiral-building blocks. In this work, a family of chiral 4,4′-biquinazoline alcohols has been conveniently prepared from the easily accessible (S)-2-acetoxycarboxylic acid chlorides by reaction sequences beginning with condensation and followed by key synthetic steps including chlorination, nickel(0)-mediated homocoupling, and deprotection in addition to being examined as potential ligands in the enantioselective addition of phenylacetylene to aldehydes. These chiral ligands can be combined with Ti(OiPr)4 and then used to catalyze the asymmetric addition of zinc acetylide, produced in situ by the reaction of phenylacetylene with diethylzinc, to aldehydes. The best enantiomeric excess obtained in this study was 75%. 相似文献
97.
The radial part of the effective mass Klein-Gordon equation for the Hulthen potential is solved by making an approximation
to the centrifugal potential. The Nikiforov-Uvarov method is used in the calculations. Energy spectra and the corresponding
eigenfunctions are computed. Results are also given for the case of constant mass. 相似文献
98.
In many situations, a worker’s ability improves as a result of repeating the same or similar tasks; this phenomenon is known as the learning effect. In this paper the learning effect is considered in a two-machine flowshop. The objective is to find a sequence that minimizes a weighted sum of total completion time and makespan. Total completion time and makespan are widely used performance measures in scheduling literature. To solve this scheduling problem, an integer programming model with n2 + 6n variables and 7n constraints where n is the number of jobs is formulated. Because of the lengthy computing time and high computing complexity of the integer programming model, the problem with up to 30 jobs can be solved. A heuristic algorithm and a tabu search based heuristic algorithm are presented to solve large size problems. Experimental results show that the proposed heuristic methods can solve this problem with up to 300 jobs rapidly. According to the best of our knowledge, no work exists on the bicriteria flowshop with a learning effect. 相似文献
99.
100.
Gülgün Yeniehirli Nuren Altunta
zta Ertan ahin Mustafa elebier Nilgün Ancn Selma Gül
zta 《Heteroatom Chemistry》2010,21(6):373-385
A new series of diorganotin complexes of the type R2SnL (L1: N‐(2‐hydroxy‐5‐chlorophenyl)‐ 3‐ethoxysalicylideneimine, R = Me, (Me2SnL1), R = n‐Bu, (n‐Bu2SnL1), R = Ph, (Ph2SnL1), L2: N‐(2‐hydroxy‐4‐nitro‐5‐chlorophenyl)‐3‐ethoxysalicylideneimine, R = Ph, Ph2SnL2, L3: N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐methoxysalicylideneimine, R = Me, (Me2SnL3), R = n‐Bu, (n‐Bu2SnL3), L4: N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐ethoxysalicylideneimine, R = Me, (Me2SnL4), R = n‐Bu, (n‐Bu2SnL4)) were synthesized and characterized by elemental analysis, infrared (IR), 1H, and 13C NMR mass spectroscopic techniques, and electrochemical measurements. Ph2SnL1 and Ph2SnL2 were also characterized by X‐ray diffraction analysis and were found to show a fivefold C2NO2 coordination geometry nearly halfway between a trigonal bipyramidal and distorted square pyramidal arrangement. The C Sn C angles in the complexes were calculated using Lockhart's equations with the 1J(117/119Sn‐13C) and 2J(117/119Sn‐1H) values from the 1H NMR and 13C NMR spectra. Biocidal activity tests against several micro‐organisms and some fungi indicate that all the complexes are mildly active against Gram (+) bacteria and the fungi, A. niger and inactive against Gram (−) bacteria. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:373–385, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20628 相似文献