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1.
da Silva Pedro Rafael Sena Laís Cristina Santana Silva Rubens Pedro Lorena de Santana Danielle Cristine Almeida Silva de Santana Fernando José Malagueño 《Analytical and bioanalytical chemistry》2019,411(16):3447-3461
Analytical and Bioanalytical Chemistry - This study aimed to determine simultaneously five major street cocaine adulterants (caffeine, lidocaine, phenacetin, diltiazem, and hydroxyzine) in human... 相似文献
2.
Prof. Miguel A. Sierra Prof. Luis Casarrubios Dr. María C. de la Torre 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7232-7242
Overuse and misuse of antibacterial drugs has resulted in bacteria resistance and in an increase in mortality rates due to bacterial infections. Therefore, there is an imperative necessity of new antibacterial drugs. Bio-organometallic derivatives of antibacterial agents offer an opportunity to discover new active antibacterial drugs. These compounds are well-characterized products and, in several examples, their antibacterial activities have been studied. Both inhibition of the antibacterial activity and strong increase in the antibiotic activity of the parent drug have been found. The synthesis of the main classes of bio-organometallic derivatives of these drugs, as well as examples of the use of structure–activity relation (SAR) studies to increase the activity and to understand the mode of action of bio-organometallic antimicrobial peptides (BOAMPs) and platensimicyn bio-organometallic mimics is presented in this article. 相似文献
3.
We construct highly edge-connected -regular graphs of even order which do not contain pairwise disjoint perfect matchings. When is a multiple of 4, the result solves a problem of Thomassen [4]. 相似文献
4.
The European Physical Journal H - The widespread positivist approach of physics research in Italy at the turn of the XIX and XX centuries did not provide a fertile ground for the scientific debate... 相似文献
5.
High refractive index hyperbranched polyvinylsulfides for planar one‐dimensional all‐polymer photonic crystals 下载免费PDF全文
Serena Gazzo Giovanni Manfredi Robert Pötzsch Qiang Wei Marina Alloisio Brigitte Voit Davide Comoretto 《Journal of Polymer Science.Polymer Physics》2016,54(1):73-80
We report on the growth and characterization of one‐dimensional (1D) planar all‐polymer photonic crystals (PhC) with high dielectric contrast (Δn = 0.3) prepared by spin coating using hyperbranched polyvinylsulfide polymers (HB‐PVS) as high refractive index material and cellulose acetate as low refractive index material. Solution processable HB‐PVS show a near ultraviolet absorption inducing an increased refractive index in the visible‐near infrared (n = 1.68, λ = 1000 nm). HBPVS:Cellulose Acetate Distributed Bragg Reflectors show a very clear fingerprint of the photonic band gap possessing the expected polarized dispersion properties as a function of the incidence angle. Moreover, engineered microcavities tuned on the weak fluorescence spectrum of the HB‐PVS show directional fluorescence enhancement effects due to spectral redistribution of the emission oscillator strength. The combination of all these properties testifies the high optical quality of the obtained photonic structures thus indicating HB‐PVS as an interesting material for the preparation of such PhC. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 73–80 相似文献
6.
Discovery,Characterization, and Analogue Synthesis of Bohemamine Dimers Generated by Non‐enzymatic Biosynthesis 下载免费PDF全文
Dr. Peng Fu Aaron Legako Scott La Prof. Dr. John B. MacMillan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3491-3495
Dibohemamines A–C ( 5 – 7 ), three new dimeric bohemamine analogues dimerized through a methylene group, were isolated from a marine‐derived Streptomyces spinoverrucosus. The structures determined by spectroscopic analysis were confirmed through the semi‐synthetic derivatization of monomeric bohemamines and formaldehyde. These reactions, which could occur under mild conditions, together with the detection of formaldehyde in the culture, revealed that this dimerization is a non‐enzymatic process. In addition to the unique dimerization of the dibohemamines, dibohemamines B and C were found to have nm cytotoxicity against the non‐small cell‐lung cancer cell line A549. In view of the potent cytotoxicity of compounds 6 and 7 , a small library of bohemamine analogues was generated for biological evaluation by utilizing a series of aryl and alkyl aldehydes. 相似文献
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Supramolecular Wiring of Benzo‐1,3‐chalcogenazoles through Programmed Chalcogen Bonding Interactions 下载免费PDF全文
Dr. Adrian Kremer Dr. Andrea Fermi Nicolas Biot Prof. Johan Wouters Prof. Dr. Davide Bonifazi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5665-5675
The high‐yielding synthesis of 2‐substituted benzo‐1,3‐tellurazoles and benzo‐1,3‐selenazoles through a dehydrative cyclization reaction has been reported, giving access to a large variety of benzo‐1,3‐chalcogenazoles. Exceptionally, these aromatic heterocycles proved to be very stable and thus very handy to form controlled solid‐state organizations in which wire‐like polymeric structures are formed through secondary N???Y bonding interactions (SBIs) engaging the chalcogen (Y=Se or Te) and nitrogen atoms. In particular, it has been shown that the recognition properties of the chalcogen centre at the solid state could be programmed by selectively barring one of its σ‐holes through a combination of electronic and steric effects exerted by the substituent at the 2‐position. As predicted by the electrostatic potential surfaces calculated by quantum chemical modelling, the pyridyl groups revealed to be the stronger chalcogen bonding acceptors, and thus the best ligand candidate for programming the molecular organization at the solid state. In contrast, the thiophenyl group is an unsuitable substituent for establishing SBIs in this molecular system as it gives rise to chalcogen–chalcogen repulsion. The weaker chalcogen donor properties of the Se analogues trigger the formation of feeble N???Se contacts, which are manifested in similar solid‐state polymers featuring longer nitrogen–chalcogen distances. 相似文献
10.
Ratios for target Ar K-shell ionization associated with single and double electron capture, as well as the ratios corresponding to total capture and the projectile K x rays, were determined for 1.8- to 2.2-MeV/u F7 + ,8 + ,9+ projectiles. This work was performed at Western Michigan University with the tandem Van de Graaff accelerator. Coincidences between emitted K-shell X-rays (both target and projectile) and the corresponding charge-changed particles were observed. The F9+ Ar K X-ray coincidence ratios for double to single capture are found to well exceed unity over the limited energy range of the measurements. Possible explanations for this anomalous behavior are discussed. 相似文献