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101.
The usually allowed Coster-Kronig L1L2,3M transitions are found not to be energetically possible for all electronic configurations with a single K-shell and multiple L-shell vacancies of Al. Consideration of these effects as related to X-ray measurements in heavy-ion-atom collisions are presented. 相似文献
102.
Six new complexes of thallium(III) of the formula (π-D)2Tl(L) (where D= cyclopentadienyl or indenyl group and L=nitro, nitrito or nitrato group) have been prepared and characterised on the basis of I. R. studies and some thermal properties of these complexes. 相似文献
103.
104.
Vatmurge NS Hazra BG Pore VS Shirazi F Deshpande MV Kadreppa S Chattopadhyay S Gonnade RG 《Organic & biomolecular chemistry》2008,6(20):3823-3830
We report herein the synthesis and biological evaluation of bile acid dimers linked through 1,2,3-triazole and bis-beta-lactam. The dimers were synthesized using 1,3-dipolar cycloaddition reaction of diazido bis-beta-lactams , and terminal alkynes derived from cholic acid/deoxycholic acid in the presence of Cu(i) catalyst (click chemistry). These novel molecules were evaluated in vitro for their antifungal and antibacterial activity. Most of the compounds exhibited significant antifungal as well as antibacterial activity against all the tested fungal and bacterial strains. Moreover, their in vitro cytotoxicities towards HEK-293 and MCF-7 cells were also established. 相似文献
105.
A new fluorescent chemosensor based on the calix[4]arene of partial cone conformation possessing a dansyl moiety has been synthesized. The chemosensor demonstrates selective optical recognition of Hg(2+) and Cu(2+) in two contrasting modes. The receptor exhibited ratiometric sensing of Hg(2+) and "ON-OFF" type of fluorescence behavior in the presence of Cu(2+). The compound behaves as a fluorescent molecular switch upon chemical inputs of Hg(2+) and Cu(2+) ions. 相似文献
106.
A novel synthesis of 2-substituted 2H-imidazo[1,5-b]isoquinoline-1,5-diones by reductive desulfurization of a variety of 2-substituted
3-thioxo-2H-imidazo[1,5-b]isoquinoline-1,5-diones is reported with nickel boride in dry methanol at ambient temperature.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–408, March, 2008. 相似文献
107.
Vandana Singh Preeti Srivastava Angela Singh Devendra Singh Tulika Malviya 《高分子科学杂志,C辑:聚合物评论》2016,56(1):113-136
This article discusses and reviews the current status and future perspectives of silica hybrids of polysaccharides and biosilicas derived thereof. The hybrids have been produced in various morphological shapes and utilized in water remediation, separation, enzyme immobilization, sensor, and biomedical fields. The polysaccharides show templating and structure directing influence in manipulation of sol gel silica hybrid materials which can be calcined to derive functional biosilicas. The development of energy storage devices and white light emitting solid phosphors may be the fields of future research. 相似文献
108.
Vandana Gawande Anil Kumar Singh Piyush Rathor Darpan Damania 《Journal of Analytical Chemistry》2016,71(6):605-609
The objective of the present study was to develop and validate a rapid and simple stability indicating analytical method for estimating Ilaprazole. Ilaprazole was subjected to different stress conditions prescribed by International Conference on Harmonization (ICH) such as hydrolysis, oxidation, photolytic and dry heat degradation conditions. The drug was very susceptible to degradation under hydrolysis and photolytic conditions, less susceptible to oxidation and stable under dry heat degradation condition. An acceptable separation of drug and its degradants was achieved by using a C-18 column and mobile phase composed of ammonium acetate buffer (pH 3.2)—acetonitrile (55: 45, v/v). Flow rate was 1 mL/min and detection wavelength was set at 303 nm. Retention time of drug was found to be 6.6 min and analysis can be completed within 10 min. The method was validated with respect to linearity, precision, accuracy, robustness, LOD and LOQ as per ICH. The method was linear (R2 = 0.996) in the range of 2.5–250 μg/mL. The recovery was in the range from 99.2–100.2%. 相似文献
109.
A fast, efficient, and diastereoselective synthesis of novel 3-oxo-4-benzothiazolylpyrazolyl-β-lactams is described. The reaction between 2-aryloxy/alkoxyacetic acid and novel benzothiazolylpyrazole-substituted imines afforded exclusive formation of trans-β-lactams. The scope of the reaction was investigated by varying different groups on substrates (R1, R2, R3, Z). All the novel compounds were characterized using various spectroscopic techniques such as FT-IR, 1H NMR, 13C NMR, elemental analysis, and mass spectrometry in representative cases. No report has been listed in the literature for the synthesis of these types of β-lactam heterocycles so far. 相似文献
110.
Aman Bhalla Garima Modi Shamsher S. Bari Anu Kumari Shiwani Berry Geeta Hundal 《Tetrahedron letters》2017,58(12):1160-1165
An efficient and operationally simple strategy for the stereoselective synthesis of novel C-3 functionalized 3-sulfonyl-β-lactam heterocycles is described. The C-3 functionalized 3-phenyl/benzylsulfonyl-β-lactams 3/3′, 5/5′ has been synthesized via Michael addition using different Michael acceptors on trans-3-phenyl/benzylsulfonyl-β-lactams 2(a–f) using K2CO3 as a base and acetonitrile/DMF as solvents. The reaction furnished exclusively cis-β-lactam adducts 3(a–r) using sterically less hindered Michael acceptors. Further, the effect of steric bulk and chiralilty of Michael acceptors was explored to achieve target C-3 functionalized β-lactams 3(s-u)/3′(s-u) and 5(a–c)/5′(a–c). The structural and stereochemical analysis of novel β-lactams were carried out using FT-IR, NMR (1H, 13C, 1H-1H COSY, 1H-13C COSY and 13C DEPT-135), elemental analysis (CHNS), mass spectrometry (EIMS and LCMS) in representative cases and single crystal X-ray crystallographic studies (3e). The cis or trans configuration of the Michael acceptor (E) at C-3 was assigned with respect to C4-H. 相似文献