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271.
Summary The preparation and characterization of CuII, CoII, NiII and HgII complexes containing 1,4-diphenylthiosemicarbazide (DPhTSC) of the type [Cu(DPhTSC-H)X.H2O]nH2O (X= Cl, Br or Ac; n=0 or 1) · [M(DPhTSC-H)2yH2O] (M=CoII or NiII; y=0 or 1) and [Hg(DPhTSC)Cl2]2 H2O and [Cu(D-PhTSC)2SO4]H2O are reported. The stereochemistry of the complexes have been studied with the help of magnetic and electronic measurements. The anomalous magnetic moments observed in all cases have been explained. The i.r. spectral studies have been used to determine the bonding sites in the complexes.  相似文献   
272.
When 6-acetoacetyl-5-methoxy- ( 1b ) and 5-acetoacetyl-6-methoxy-2,3-diphenylbenzofuran ( 2b ) were treated with cyanoacetamide, the corresponding pyridinecarbonitriles were obtained. Compounds 1b and 2b reacted with ethyl cyanoacetate in the presence of ammonium acetate to give the benzofuranyl-pyrone derivatives. This reaction, when carried out in presence of diethylamine, led to the formation of furochromones. Hydrazine hydrate, phenylhydrazine and semicarbazide hydrochloride reacted with 1b and 2b with the formation of the corresponding pyrazoles. The corresponding isoxazole derivatives were formed by the reaction of 1b and 2b with hydroxylamine hydrochloride.  相似文献   
273.
Summary A general method for the formation of cyclic sulfenylated 2-oxazoline, 2-thiazolines, 5,6-dihydro-4H-1,3-oxazines, and 5,6-dihydro-4H-1,3-thiazines is described. The procedure employs arylsulfenyl chloride and ethyldiisopropylamine to generate an episulfonium ion intermediate from which the cyclic products arise by internal nucleophilic displacement.
Sulfenocyclisierung ungesättigter Harnstoffe und Thioharnstoffe
Zusammenfassung Eine allgemeine Methode zur Herstellung cyclischer sulfenylierter 2-Oxazoline, 2-Thiazoline, 5,6-Dihydro-4H-1,3-oxazine und 5,6-Dihydro-4H-1,3-thiazine wird beschrieben. Aus Arylsulfenylchlorid und Ethyldiisopropylamin entsteht ein Episulfoniumion als Zwischenprodukt; dieses bildet durch nucleophile Umlagerung die cyclischen Produkte.
  相似文献   
274.
Journal of Radioanalytical and Nuclear Chemistry - High radioactive anomalies were recorded in the variegated claystones at the middle member of Um Bogma Formation, the eU-content reaches...  相似文献   
275.
    
Due to the rapidly increasing number of pathogenic bacteria, viruses, and tumor cells that possess resistance toward established therapies, lead structures for the development of new drugs are in high demand. The plant material of Tanacetum sinaicum is considered a prolific source of the potent biologically active sesquiterpene Tanacetolide A ( 1 ). In our research, we focused on the structural transformation of the substrate Tanacetolide A (compound 1 ) by suspended culture of the novel locally isolated terrestrial fungus Rhizopus oryzae KX685359. The fungal transformation resulted in the formation of 1β,3α-dihydroxy-6α-hydroperoxy-eudsm-4(15)-ene 12-oic acid ( 2 ) with higher antiproliferative activity against colon cancer cell line (Caco-2) than that of the parent compound ( 1 ).  相似文献   
276.
    
In the present investigation, a simple and straightforward methodology for the preparation of novel bifunctional thienopyrazolopyrazines 4a–d has been reported. Synthesis of thieno or furopyrazolopyrazines 5a , b , e , f was achieved by the reaction of o-amino-esters 4a , b , e , f with 2,5-dimethoxytetrahydrofuran. The latter pyrrolyl derivatives 5a , b , e , f were used as starting intermediates for the synthesis of new pyrimido, pyrido, and pyrazino heterocycles fused to the thieno or furopyrazolopyrazine moiety. Furthermore, alkaline hydrolysis of the o-amino-ester 4a followed by acidification afforded the corresponding o-amino carboxylic acid 15 , which was used as a versatile precursor for the synthesis of other heterocyclic compounds fused to the thienopyrazolopyrazine ring system, namely: pyrimidine, oxazine, oxazepine, and pyridine derivatives 16–23 . The chemical structures of the synthesized compounds were confirmed on the basis of elemental and spectral analyses (Fourier-transform infrared spectroscopy [FT-IR], 1H nuclear magnetic resonance [NMR], and mass spectroscopy [MS] in addition to 13C NMR for some of them). Moreover, from the biological screening, we found that most of the tested compounds exhibited promising antifungal, antibacterial, and anti-inflammatory activities compared with the corresponding reference drugs.  相似文献   
277.
    
A series of Co(II), Cu(II), Y(III), Zr(IV), La(III), and U(VI) complexes derived from 2-(2-hydroxybenzylidinemine)-benzoic acid (L) ligand were synthesized. The mode of bonding of L and the structure of its metal complexes were investigated using different analytical and spectral tools (FT-IR, UV–Vis, 1H NMR, mass, and XRD). The ligand chelated with the metal ions as a neutral bidentate through oxygen and azomethine nitrogen atoms. All metal complexes adopted octahedral geometry with characteristic color for metal ions. The results of magnetic moment measurements supported paramagnetic for some complexes (Co(II) and Cu(II)) and diamagnetic phenomena for the other complexes. The thermal decomposition of the ligand along with its metal complexes was explained. The molar conductance values of all complexes in (DMF) were found in the range 154.50 to 250.20 S cm2 mol−1 at room temperature. The activation thermodynamic parameters, such as E*, ΔH*, ΔS* and ΔG*, were calculated from the DTG curves using Coats–Redfern (CR) and Horowitz–Metzeger (HM) methods at n = 1 or n ≠ 1. The nematicidal activity of the synthesized L and their metal complexes was screened.  相似文献   
278.
279.
Journal of Thermal Analysis and Calorimetry - The purpose of this work is to investigate the opportunity of re-using M&G wastes to get novel PP composites. Recycling of marble and granite...  相似文献   
280.
The synthetic utility of 2-mercaptonicotinonitriles 3 and 4, as well as 2-mercapto-4-oxo-6-phenyl-1,4-dihydropyrimidine-5-carbonitrile 20 as building blocks for novel bis- and poly(pyridines), along with poly(pyrimidines) via alkylation with the corresponding bis- and poy(halo) compounds was investigated. Spectroscopic and theoretical studies confirmed the S-alkylation rather than the N-alkylation.  相似文献   
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