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41.
A selective reduction of aldehydes to alcohols using benzyltriethy lammoniun chloride - zinc - Methanol System is done.  相似文献   
42.
Aldehydes and ketones are reduced to correspondig alcohols in good yields at room temperature.  相似文献   
43.
Antibiotic susceptibility test (AST) discs are used as an in-vitro diagnostic tool to select the appropriate antibiotic to treat an infection. Generally, the concentration of the drug loaded on to the AST discs is measured by studying its activity against quality control organisms. This methodology has several limitations—it is time consuming, requires trained manpower, has a wider acceptance criteria of zone of inhibitions—causing ambiguity in judging smaller variations in drug concentration. To overcome these issues, we have developed and validated high-performance liquid chromatographic (HPLC) methods for the determination of strength of AST discs for in-house researched antibiotics, namely Levonadifloxacin/WCK 771, Nafithromycin/WCK 4873, Cefepime-Tazobactam/WCK 4282, and Cefepime-Zidebactam/WCK 5222. The drugs were extracted from the AST discs using an appropriate solvent. The developed methods are simple, accurate, precise, reproducible, rugged, and robust. They are efficient in terms of time, and can be easily conducted in a quality control laboratory during release as well as stability evaluation of AST disc. Application of HPLC methods for the determination of strength of AST discs ensures flawless quality and, consequently, a better selection of drugs to treat bacterial infections in clinics.  相似文献   
44.
Chromatographia - WCK 771 is a novel antibacterial drug recently launched in India for the treatment of acute bacterial skin and skin structure infections (ABSSSI). This report describes...  相似文献   
45.
A simple and efficient synthesis of previously unknown benzosubstituted dioxaphosphonines containing a quinoxaline subunit is described. Reasonably good yields of the products, mild reaction conditions, and convenient work-up are the advantages of this method. The procedure does not require any catalyst or activator and can be efficiently achieved via dianion cyclization. All the synthesized compounds have been characterized by satisfactory elemental analyses and spectral (IR, 1H, 13C, 31P NMR, and mass) studies.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   
46.
Dialkyldithiophosphate derivatives of macrocyclic complexes of Pb(II), having N2S2 potential donors, of the general formula, [Pb(L)S2P(OR)2] (where L = macrocyclic ligands L1, L2, L3, L4 & L5 and R = CH3-, C3H7 n- & C3H7 i-) have been Synthesized from the reactions of [Pb(L)X2] (where X = Cl, NO3, or CH3COO) with sodium dialkyl dithiophosphates in 1:2 molar ratios in THF. Fifteen new derivatives have been synthesized by the combination of five macrocyclic complexes of 14–20 member rings with three different types of dialkyldithiophosphate. These compounds have been characterized by elemental analysis, molar conductance, molecular weight determination, IR, 1H NMR, 13C, and 31P NMR. Molecular weight determinations of these complexes indicate their monomeric nature. An octahedral structure is proposed.  相似文献   
47.
Abstract

The films of poly(4,4′-cyclohexylidene diphenylene-m-benzene disulfonate) (PSBB, 0.610 mm thick) and poly(4,4′-cyclohexylidene diphenylene-toluene-2,4-disulfonate) (PSBT, 0.537 mm thick) showed 8.23 ± 0.25 and 9.6 ± 0.245 kV, respectively, as the dielectric breakdown voltage (ac) in air at room temperature. The same films have 8.8 × 1011 and 7.2 × 1014 ω°Cm volume resistivity. PSBB (40 μm thick) and PSBT (50 μm thick) films have tensile strengths of 1971 and 1677 kg/cm2 and percent elongations of 1.3 and 1.2, respectively. The static hardnesses of PSBB (0.178 mm thick) and PSBT (0.190 mm thick) at three different loads (15–60 g) are 12.8–15.5 and 14.5–16.5 kg/mm2, respectively. PSBB and PSBT are thermally stable up to about 355°C in an N2 atmosphere and involve two-step degradation. DSC and DTA showed T g at about 125–127 and 138–142°C, respectively, for PSBB and PSBT in N2. PSBB and PSBT have comparable breakdown voltages and volume resistivity with some useful plastics whereas they have superior T g and thermal stability with retention of excellent solubility in common solvents over polysulfonates without a cardo group. Thus, the cardo (cyclo-hexyl) group has enhanced thermal and mechanical properties with excellent solubility and easy processing.  相似文献   
48.
Solid–liquid phase‐transfer conditions were employed for the first time in the Thorpe reaction to synthesize 4‐amino‐1‐aryl‐3,5‐substituted‐1H‐pyrazoles 3. Aryl amines were diazotized and coupled with various active methylene compounds such as cyano acetamide, cyanoacetophenone, malononitrile, and ethyl cyanoacetate, resulting into α‐arylhydrazononitriles 1. Cyclization of 1 using α‐bromo ketones or esters resulted in compounds 3.  相似文献   
49.
A six‐step general and very efficient synthesis of 4‐(arylmethyl)‐5,5‐dialkyldihydrofuranones starting from corresponding aryl aldehyde has been developed. Solafuranone, a novel furanone isolated from the Chinese folk medicine Solanum indicum, has been accomplished starting from 2,6‐dimethylbenzaldehyde in six steps in an overall yield of 70%. Contrary to expectations, solafuranone and its analogue failed to exhibit any significant cytotoxicity against A549 (lung adenocarcinoma) and HL60 (leukemia cells) cell lines.  相似文献   
50.

Surgery, chemotherapy and radiotherapy, the conventional treatment modalities of cancer though successful are limited by presence of residual tumor cells, toxic side-effects and treatment resistance, thus raising the need for investigating other novel approaches. Here, we have used a cold atmospheric plasma (CAP) jet and assessed the in vitro efficacy in gingivobuccal squamous cell carcinoma (GB-SCC) – ITOC-03, breast adenocarcinoma—MCF7 and HEK293 cells. Cells lines were subjected to varying doses of ionizing radiation (0, 2, 4, 6, 8 Gy) and CAP jet treatment (0, 60, 180, 240, 300 s). CAP jet treatment showed time dependent increase in H2O2 and NO2? concentration. Cell viability assay showed potent effect of CAP jet on all three cell lines in comparison to radiation treatment, while helium gas treatment showed minimal inhibitory effect. Irradiated, CAP jet and helium gas treated cells showed loss of nucleic acid features, 788 cm?1 and 1340 cm?1 in Raman spectra, indicating DNA damage. Principal Component Analysis (PCA) showed distinct classification of CAP-treated and control cells, while Principal Component – Linear Discriminant Analysis (PC-LDA) based classification of Raman spectra showed ITOC-03 and HEK293 cells to be sensitive to CAP jet and radiation treatment in comparison to MCF7 cells. Collectively, cell viability assay and Raman spectroscopy have shown potent effect of CAP jet in GB-SCC and breast adenocarcinoma cells.

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