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591.
Amara Venkateswara Rao Basa Ashok Vatti Chandrasekhar Gopireddy Venkata Subbareddy Anumakonda Varada Rajulu 《International Journal of Polymer Analysis and Characterization》2018,23(6):493-501
Nanocomposite cotton fabrics with in situ-generated silver nanoparticles (AgNPs) were prepared by using Pterocarpus santalinus (Red sanders) extract in water as a reducing agent. The formation of AgNPs was analyzed by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy. The SEM analysis of nanocomposites showed the presence of spherical AgNPs with a size range of 71–90?nm. FTIR spectra showed the involvement of hydroxyl and methylene groups of cellulose matrix in reducing the silver salt into AgNPs in the presence of red sanders powder extract as reducing agent for the in situ generation of AgNPs. These nanocomposite fabrics exhibited good antibacterial activity against Gram positive and Gram negative bacteria. 相似文献
592.
Inside Cover: Sequential 1,4‐/1,2‐Addition of Lithium(trimethylsilyl)diazomethane onto Cyclic Enones to Induce C−C Fragmentation and N−Li Insertion (Angew. Chem. Int. Ed. 6/2016)
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593.
Synthesis of New Triazole and Oxadiazole Derivatives of Quinazolin‐4(3H)‐one and Their Antimicrobial Activity
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Kotla Veena Vani Garlapati Ramesh Chunduri Venkata Rao 《Journal of heterocyclic chemistry》2016,53(3):719-726
A series of new triazole derivatives of quinazolin‐4(3H)‐one and new oxadiazole derivatives of quinazolin‐4(3H)‐one were synthesized. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral data. All the newly synthesized compounds were screened for antibacterial activity against Staphylococcus aureus, Bacillus subtilis (gram‐positive bacteria), Escherichia coli, Pseudomonas aeruginosa (gram‐negative bacteria), and antifungal activity was carried out against Candida albicans and Aspergillus niger. 相似文献
594.
Polepally AR Kumar VV Bhamidipati R Kota J Naveed SA Reddy KH Mamidi RN Selvakumar N Mullangi R Srinivas NR 《Biomedical chromatography : BMC》2008,22(9):960-976
The discovery of small-molecule novel chemical entities (NCEs) is often a complex play between appropriate structural requirements and optimization of the desired efficacy, safety and pharmacokinetic properties. One of the typical structural variants such as having an active carbon-carbon double bond (alpha, beta-unsaturated carbonyl group) in xenobiotics may lead to stability issues. Such functionalities are extremely reactive, paving way to nucleophilic attack by endogenously occurring and ubiquitous nucleophiles like thiols. While it is easy to make a unilateral decision to not pursue the development of xenobiotics with such functionalities, we question the wisdom of such a decision. In this report, we present in vitro methodologies with appropriate examples to illustrate the ease of assessing the reactivity of the xenobiotics containing double bonds with a known nucleophile. The protocols involve simple reaction procedures followed by measurements using standard laboratory equipments (UV spectrophotometer, HPLC and LC-MS). Our data suggests that not all xenobiotics with carbon-carbon double bonds readily form a Michael's adduct product with glutathione. Hence, the criterion for dropping discovery compounds because of alpha,beta-unsaturated double bonds needs to be reconsidered. Copyright (c) 2008 John Wiley & Sons, Ltd. 相似文献
595.
The reaction of β-chloroacrolein with 1 equiv of 2-aminophenol in DMF proceeds smoothly to afford 11-hydroxy derivative of chromenoquinoline in good yield. This single pot method allows for a rapid access to a variety of chromenoquinolines or oxepinoquinolines depending on the nature of β-chloroacrolein used. The structures were established by spectroscopic data and further confirmed by X-ray diffraction analysis. A plausible mechanism for this reaction has been proposed. The reaction seemed to proceed via a chloroimine species, whose intermediacy has been established, followed by the construction of the fused quinoline ring. 相似文献
596.
Gowravaram Sabitha Narjis Fatima E. Venkata Reddy J.S. Yadav 《Tetrahedron letters》2008,49(42):6087-6089
The total syntheses of (6R)-6-[(2R)-2-hydroxyhexyl]tetrahydro-2H-2-pyranone and 7-hydroxy-5-dodecanolide are described utilizing a Prins reaction and ring closing metathesis reaction sequence. 相似文献
597.
Naga Venkata Sastry Mudiganti 《Tetrahedron letters》2008,49(49):6980-6983
Asymmetric synthesis of all the four stereoisomers of cis-3,4-dihydroxy-3,4-dihydromollugins 4 and 6 and trans-3,4-dihydroxy-3,4-dihydromollugins 5 and 7 was achieved. The O-methoxymethyl mollugin derivatives were dihydroxylated to (−)- and (+)-cis-3,4-dihydroxy-3,4-dihydromollugin derivatives using both AD-mix-α and AD-mix-β. Deprotection of the MOM-ethers of cis-dihydroxy compounds resulted in the targeted stereoisomers (−)-(3R,4R)-cis-3,4-dihydroxy-3,4-dihydromollugin 4, (−)-(3R,4S)-trans-3,4-dihydroxy-3,4-dihydromollugin 5, (+)-(3S,4S)-cis-3,4-dihydroxy-3,4-dihydromollugin 6 and (+)-(3S,4R)-trans-3,4-dihydroxy-3,4-dihydromollugin 7. These routes were paved with difficulties, for example, incompatibility of the substrates with AD-mixes, the unexpected formation of trans-dihydroxy compounds and failures in deprotection protocols. 相似文献
598.
Journal of Cluster Science - The current work demonstrated an in vitro model of diastase capped gold nanoparticles (Au NPs) and nanoplates (Au NPts) as unique contrast agents for molecular imaging... 相似文献
599.
Luísa R. Carvalho Marta C. Corvo Ramu Enugala M. Manuel B. Marques Eurico J. Cabrita 《Magnetic resonance in chemistry : MRC》2010,48(4):323-330
The solid‐phase synthesis (SPS) of a structurally complex glycopeptide, using Sieber amide resin, was monitored by high resolution magic angle spinning NMR, demonstrating the further application of this technique. A synthetic peptidoglycan derivative, a precursor of a biologically active PGN, known to be involved in the cellular recognition, was prepared by SPS. The synthesis involved the preparation of an N‐alloc glucosamine moiety and the synthesis of a simple amino acid sequence L ‐Ala‐D ‐Glu‐L ‐Lys‐D ‐Ala‐D ‐Ala. Last step consisted the coupling, on solid‐phase, of the protected muramyl unit to the peptide chain. Proton spectra with good suppression of the polystyrene signals in swollen resin samples were obtained in DMF‐d7 as a solvent and by using a nonselective 1D TOCSY/DIPSI‐2 scheme, thus allowing to follow the SPS without losses of compound and cleavage from the resin. The assignment of the proton spectra of the resin‐bound amino acid sequence and of the bound glycopeptide was achieved through the combination of MAS COSY, TOCSY and NOESY. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
600.