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71.
Moideen Musthafa Ramaiah Konakanchi 《Phosphorus, sulfur, and silicon and the related elements》2020,195(4):331-338
AbstractA series of aroyl selenourea dibenzosuberene (1–3) derivatives were synthesized and characterized by different analytical methods and single crystal X-ray crystallography. Quantum chemical computations were made using DFT to determine the structural and molecular properties of the compounds. The in vitro antibacterial action of the compounds was evaluated against chosen gram-negative (Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli), and gram-positive (Bacillus subtilis, Staphylococcus aureus, and Staphylococcus epidermidis) bacteria for their antifungal activity against Curvularia lunata, Penicillium notatum, and Aspergillus niger. Using molecular docking studies, the binding modes were understood along with the mechanism in opposing the target protein MurB. 相似文献
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An aerobic oxidative cross-dehydrogenative coupling reaction between sp(3) C-H and sp(2) C-H bonds is developed by employing a vanadium catalyst (10 mol%) in an aqueous medium using molecular oxygen as the oxidant. This environmentally benign strategy exhibits larger substrate scope and shows high regioselectivity. 相似文献
74.
Sanju KS Neelakandan PP Ramaiah D 《Chemical communications (Cambridge, England)》2011,47(4):1288-1290
We observed FRET between an excimer of a partially intercalated cyclophane and ethidium bromide, a classical intercalator in presence of DNA and by fine-tuning the molar concentrations of these three components, we could generate white light emission in the aqueous and non-aqueous media. 相似文献
75.
A new spectrophotometnc method for the estimation of bismuth with EDTA, using iron-salicylate complex as the indicator, has been developed. The determinations were carried out by measuring the absorbance at 520 mmu. of solutions containing bismuth, iron(III), salicylic acid and various quantities of EDTA, at pH 0.5. It has been shown from the stability constants of the complexes present that before the end-point iron(III) will not react appreciably with the Bi-EDTA complex. The interference from iron(III) in the estimation of bismuth, which is a serious drawback in many other methods, is eliminated in the present method, as iron(III) acts as the indicator. 相似文献
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Devan N Sridhar PR Prabhu KR Chandrasekaran S 《The Journal of organic chemistry》2002,67(26):9417-9420
Tetrathiomolybdate provides an easy access to beta-hydroxy disulfides, beta-hydroxy sulfides, and selenides from epoxides in a tandem, multistep process in one pot. This strategy has been utilized effectively in the construction of thiabicylo[3.2.2]nonane derivative 24. 相似文献
80.
Amino Acid–Porphyrin Conjugates: Synthesis and Study of their Photophysical and Metal Ion Recognition Properties 下载免费PDF全文
Albish K. Paul Suneesh C. Karunakaran Joshy Joseph Danaboyina Ramaiah 《Photochemistry and photobiology》2015,91(6):1348-1355
Synthesis, photophysical and metal ion recognition properties of a series of amino acid‐linked free‐base and Zn‐porphyrin derivatives (5–9) are reported. These porphyrin derivatives showed favorable photophysical properties including high molar extinction coefficients (>1 × 105 m ?1 cm?1 for the Soret band), quantum yields of triplet excited states (63–94%) and singlet oxygen generation efficiencies (59–91%). Particularly, the Zn‐porphyrin derivatives, 6 and 9 showed higher molar extinction coefficients, decreased fluorescence quantum yields, and higher triplet and singlet oxygen quantum yields compared to the corresponding free‐base porphyrin derivatives. Further, the study of their interactions with various metal ions indicated that the proline‐conjugated Zn‐porphyrins (6 and 9) showed high selectivity toward Cu2+ ions and signaled the recognition through changes in fluorescence intensity. Our results provide insights on the role of nature of amino acid and metallation in the design of the porphyrin systems for application as probes and sensitizers. 相似文献