Four rhenium(I) complexes ReL1-ReL4 based on dipyrido3,2-a:2variant prime,3variant prime-cphenazine (L1) and derivatives L2-L4 ligands (L2: 10,13-dibromodipyrido3,2-a:2variant prime,3variant ...prime-cphenazine, L3: 10-bromo-13-carbazolyl-dipyrido3,2-a:2variant prime,3variant prime-cphenazine, L4: 10,13-dicarbazolyldipyrido3,2-a:2variant prime,3variant prime-cphenazine) were synthesized and characterized. The Re(I) complexes ReL1-ReL4 show photoluminescent emissions at 556, 582, 637 and 662 nm, respectively, assigned to d Formula omitted. (Re)-> Formula omitted. low * (diimine) MLCT phosphorescence in CH2Cl2 solution. The carbazole containing complexes ReL3 and ReL4, as compared to ReL1, exhibit higher luminescence. These observations imply that modification of diimine rhenium(I) carbonyl complexes with carbazole moiety would lead to efficient phosphorescent properties. PUBLICATION ABSTRACT
Coronaviruses (CoVs) traffic frequently between species resulting in novel disease outbreaks, most recently exemplified by the newly emerged SARS-CoV-2, the causative agent of COVID-19. Here, we show ...that the ribonucleoside analog β-d-N
-hydroxycytidine (NHC; EIDD-1931) has broad-spectrum antiviral activity against SARS-CoV-2, MERS-CoV, SARS-CoV, and related zoonotic group 2b or 2c bat-CoVs, as well as increased potency against a CoV bearing resistance mutations to the nucleoside analog inhibitor remdesivir. In mice infected with SARS-CoV or MERS-CoV, both prophylactic and therapeutic administration of EIDD-2801, an orally bioavailable NHC prodrug (β-d-N
-hydroxycytidine-5'-isopropyl ester), improved pulmonary function and reduced virus titer and body weight loss. Decreased MERS-CoV yields in vitro and in vivo were associated with increased transition mutation frequency in viral, but not host cell RNA, supporting a mechanism of lethal mutagenesis in CoV. The potency of NHC/EIDD-2801 against multiple CoVs and oral bioavailability highlights its potential utility as an effective antiviral against SARS-CoV-2 and other future zoonotic CoVs.
When considering the price change of the underlying fractal transmission system, a fractional Black–Scholes(B-S) model with an α-order time fractional derivative is derived. In this paper, we discuss ...the numerical simulation of this time fractional Black–Scholes model (TFBSM) governing European options. A discrete implicit numerical scheme with a spatially second-order accuracy and a temporally 2−α order accuracy is constructed. Then, the stability and convergence of the proposed numerical scheme are analyzed using Fourier analysis. Some numerical examples are chosen in order to demonstrate the accuracy and effectiveness of the proposed method. Finally, as an application, we use the TFBSM and the above numerical technique to price several different European options.
This review covers the strategies for the synthesis of 9H‐pyrrolo1,2‐aindole and 9H‐pyrrolo1,2‐aindol‐9‐one derivatives. Both metal‐promoted or non‐metal catalyzed transformations will be developed, ...including some relevant applications.
Previous literature emphasizes the importance of a closing call auction system because it can not only improve the price discovery effect, but also mitigate the possibility of price manipulation. ...However, Korea Exchange, which has adopted a closing call auction system, has still suffered from the price manipulation, most cases of which are likely to be related to the derivatives contracts. Based on this environment, this paper investigates why KRX experiences the closing price manipulations so much, even though it adopted the closing call auction system. Generally, a price manipulation occurs when the legal/administrative penalty is less than the expected economic gain or when a specific market structure increases an incentive to manipulate the price. In this paper, we find that the adoption of a closing call auction price as a settlement price for KOSPI derivatives contracts strengthens the incentive for closing price manipulation, which is supported by Kyle (2007). Kyle (2007) shows that if a closing price is used as a settlement price and investors can execute the ‘market-on-expiration orders’ surely, the derivatives with cash settlement are susceptible to the price manipulation such as squeezing or cornering, equally as the derivatives with physical settlement. As such, KRX is the only financial market that satisfies the above conditions. This paper tries to verify this argument by introducing the Hong Kong Exchange case, the Korean ELS-related manipulation case and the Deutsche Bank case. Therefore, we strongly recommend changing the settlement price of KRX derivatives contracts into an average price, which is similar with the well-developed financial markets.
A mild and efficient one-pot reaction for the synthesis of 1-substituted beta-carboline derivatives via the Minisci reaction has been developed with good yields and selectivity. In addition, the ...mechanism of the 1-substituted beta-carboline derivatives by means of the nucleophilic radical is described. PUBLICATION ABSTRACT
The benzene moiety is the most prevalent ring system in marketed drugs, underscoring its historic popularity in drug design either as a pharmacophore or as a scaffold that projects pharmacophoric ...elements. However, introspective analyses of medicinal chemistry practices at the beginning of the 21st century highlighted the indiscriminate deployment of phenyl rings as an important contributor to the poor physicochemical properties of advanced molecules, which limited their prospects of being developed into effective drugs. This Perspective deliberates on the design and applications of bioisosteric replacements for a phenyl ring that have provided practical solutions to a range of developability problems frequently encountered in lead optimization campaigns. While the effect of phenyl ring replacements on compound properties is contextual in nature, bioisosteric substitution can lead to enhanced potency, solubility, and metabolic stability while reducing lipophilicity, plasma protein binding, phospholipidosis potential, and inhibition of cytochrome P450 enzymes and the hERG channel.
A zoo of diffeomorphism groups on Michor, Peter W; Mumford, David
Annals of global analysis and geometry,
12/2013, Letnik:
44, Številka:
4
Journal Article
Recenzirano
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).We consider the groups ..., ..., and ... of smooth diffeomorphisms on ... which differ from the identity by a function ...which is in either ... (bounded in all derivatives), ..., or ... (rapidly decreasing). We show that all these groups are smooth regular Lie groups.
Compound identification from accurate mass MS/MS spectra is a bottleneck for untargeted metabolomics. In this study, we propose nine rules of hydrogen rearrangement (HR) during bond cleavages in ...low-energy collision-induced dissociation (CID). These rules are based on the classic even-electron rule and cover heteroatoms and multistage fragmentation. We evaluated our HR rules by the statistics of MassBank MS/MS spectra in addition to enthalpy calculations, yielding three levels of computational MS/MS annotation: “resolved” (regular HR behavior following HR rules), “semiresolved” (irregular HR behavior), and “formula-assigned” (lacking structure assignment). With this nomenclature, 78.4% of a total of 18506 MS/MS fragment ions in the MassBank database and 84.8% of a total of 36370 MS/MS fragment ions in the GNPS database were (semi-) resolved by predicted bond cleavages. We also introduce the MS-FINDER software for structure elucidation. Molecular formulas of precursor ions are determined from accurate mass, isotope ratio, and product ion information. All isomer structures of the predicted formula are retrieved from metabolome databases, and MS/MS fragmentations are predicted in silico. The structures are ranked by a combined weighting score considering bond dissociation energies, mass accuracies, fragment linkages, and, most importantly, nine HR rules. The program was validated by its ability to correctly calculate molecular formulas with 98.0% accuracy for 5063 MassBank MS/MS records and to yield the correct structural isomer with 82.1% accuracy within the top-3 candidates. In a test with 936 manually identified spectra from an untargeted HILIC-QTOF MS data set of human plasma, formulas were correctly predicted in 90.4% of the cases, and the correct isomer structure was retrieved at 80.4% probability within the top-3 candidates, including for compounds that were absent in mass spectral libraries. The MS-FINDER software is freely available at http://prime.psc.riken.jp/.
This paper investigates empirically the modelling issues for the stochastic processes underlying KOSPI200 index options. Empirical results show that we need to incorporate two factor stochastic ...volatility processes to have a good option pricing performance. However, the number of the leverage channel is not an important issue for the modelling of the KOSPI200 index options. Our results also show that the models with finite activity large jumps outperform that with infinite activity small jumps for the financial crisis period. On the while, for the pre-crisis period, there is no clear superiority or inferiority between both jumps models.
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