Quantized electron accumulation states in indium nitride studied by angle-resolved photoemission spectroscopy

Electron accumulation states in InN have been measured using high resolution angle-resolved photoemission spectroscopy (ARPES). The electrons in the accumulation layer have been discovered to reside in quantum well states. ARPES was also used to measure the Fermi surface of these quantum well states, as well as their constant binding energy contours below the Fermi level E(F). The energy of the Fermi level and the size of the Fermi surface for these quantum well states could be controlled by varying the method of surface preparation. This is the first unambiguous observation that electrons in the InN accumulation layer are quantized and the first time the Fermi surface associated with such states has been measured.     

Development of a Surfactant/Platinum Composite for Sensitive Cardio‐selective Beta Blocker Detection and their Theoretical Studies

An electrooxidative behavior of beta‐blocker drug esmolol was thoroughly investigated by using glassy carbon electrode modified with sodium dodecyl sulfate‐based platinum nanoparticles. The designed nanosensor exhibited remarkable electro‐catalytic effect by dramatically boosting the signal of the esmolol as compared to the bare electrode with detection limit up to picomolar. The effects of pH, scan rate, temperature, deposition potential, deposition time, effect of electrolyte and interfering agents were investigated to optimize conditions for getting intense signal of the analyte. Under optimized experimental conditions, a linear calibration plot for esmolol with a detection limit of 60 pM was obtained. The analyte sensing ability of the modified electrode was supported by the application of theoretical studies that showed favorable interaction between sodium dodecyl sulfate/platinum nanoparticles composite and esmolol. In this study, our aim was to developed a nanosensor for the sensitive detection of esmolol by electrochemical assay. We tried a lot of different modification style and modifiers for creating a sensitive nanosensor for esmolol. This nanosensor can be applied to the esmolol in serum sample without using any further separation, evaporation or precipitation steps. Application could apply in serum sample to test accuracy of our sensor and method. The high recovery results were observed in serum study.     

Flavonoids of Crataegus microphylla

Crataegus microphylla C. Koch is one of the 17 species of Crataegus growing in Turkey [H.P.T. Ammon and R. Kaul (1994). Dtsch. Apoth. Ztg., 134, 2433, 2521, 2631.]. This report is part of a series on the chemical investigations of Crataegus species from Turkey. Nine flavonoids have been isolated from the leaves and flowers of C. microphylla C. Koch. The amounts of the flavonoids from the leaves and flowers of the plant were determined.     

Electrochemical Investigation of Ruxolitinib: Sensitive Voltammetric Assay in Drug Product and Human Serum by Using Different Solid Electrodes

Ruxolitinib (RUX), a compound of the pyrrolopyrimidines class with activity as a tyrosine kinase inhibitory drug, is used to treat myelofibrosis. This study is reported for the detailed electrochemical behavior of RUX. The effects of supporting electrolyte, pH, and scanning rate on the peak potentials and currents of RUX were investigated by BDDE and GCE using different voltammetric techniques. Under optimum experimental conditions, calibration curves for RUX were obtained as 4 μM–80 μM and 1 μM–80 μM with a limit of detection (LOD) of 0.517 μM and 0.192 μM by the GCE and BDDE, respectively using DPV.     

Applications of Transition‐Metal‐Catalyzed Asymmetric Allylic Substitution in Total Synthesis of Natural Products: An Update

Metal‐catalyzed asymmetric allylic substitution (AAS) reaction is one of the most synthetically useful reactions catalyzed by metal complexes for the formation of carbon‐carbon and carbon‐heteroatom bonds. It comprises the substitution of allylic substrates with a wide range of nucleophiles or S_N2′‐type allylic substitution, which results in the formation of the above‐mentioned bonds with high levels of enantioselective induction. AAS reaction tolerates a broad range of functional groups, thus has been successfully applied in the asymmetric synthesis of a wide range of optically pure compounds. This reaction has been extensively used in the total synthesis of several complex molecules, especially natural products. In this review, we try to highlight the applications of metal (Pd, Ir, Mo, or Cu)‐catalyzed AAS reaction in the total synthesis of the biologically active natural products, as a key step, updating the subject from 2003 till date.     

Complete mappings and Carlitz rank

The well-known Chowla and Zassenhaus conjecture, proven by Cohen in 1990, states that for any \(d\ge 2\) and any prime \(p>(d^2-3d+4)^2\) there is no complete mapping polynomial in \(\mathbb {F}_p[x]\) of degree d. For arbitrary finite fields \(\mathbb {F}_q\), we give a similar result in terms of the Carlitz rank of a permutation polynomial rather than its degree. We prove that if \(n<\lfloor q/2\rfloor \), then there is no complete mapping in \(\mathbb {F}_q[x]\) of Carlitz rank n of small linearity. We also determine how far permutation polynomials f of Carlitz rank \(n<\lfloor q/2\rfloor \) are from being complete, by studying value sets of \(f+x.\) We provide examples of complete mappings if \(n=\lfloor q/2\rfloor \), which shows that the above bound cannot be improved in general.     

Recent Development in the Design of Neoglycoliposomes Bearing Arborescent Architectures

This brief review highlights systematic progress in the design of synthetic glycolipid (neoglycolipids) analogs evolving from the conventional architectures of natural glycosphingolipids and gangliosides. Given that naturally occurring glycolipids are composed of only one hydrophilic sugar head-group and two hydrophobic lipid tails embedded in the lipid bilayers of the cell membranes, they usually require extraneous lipids (phosphatidylcholine, cholesterol) to confer their stability. In order to obviate the necessity for these additional stabilizing ingredients, recent investigations have merged dendrimer chemistry with that of neoglycolipid syntheses. This singular approach has provided novel glycoarchitectures allowing reconsidering the necessity for the traditional one to two hydrophilic/hydrophobic ratio. An emphasis has been provided in the recent design of modular arborescent neoglycolipid syntheses coined glycodendrimersomes.     

Synthesis of some novel thiocyanotopurine derivatives and investigation of their antimicrobial activity and DNA interactions

A series of 6-thiocyanatopurine derivatives introduced with different alkyl groups in position 9 was synthesized. The structures of the synthesized compounds were evaluated via spectroscopic methods and elemental methods of analyses. All the synthesized compounds were screened for their antibacterial activities against Gram-positive and Gram-negative bacteria and for their antifungal activities against yeast strains. All the synthesized compounds showed better antibacterial activities against Gram-positive bacteria compared to Gram-negative bacteria. DNA interactions with pBR322 DNA were determined. Most of the compounds caused conformational changes in DNA.