The anti-HCV,Sofosbuvir, versus the anti-EBOV Remdesivir against SARS-CoV-2 RNA dependent RNA polymerase in silico

Molecular Diversity - Coronavirus diseases 2019 (COVID-19) are seriously affecting human health all over the world. Nucleotide inhibitors have promising results in terms of its efficacy against...     

Uses of cyclohexan-1,3-dione for the synthesis of tetrahydrochromeno[3,4-c]chromen derivatives with anti-tumor activities

Cyclohexan-1,3-dione ( 1 ) was used as the key starting material, which reacted with salicylaldehyde ( 2 ) and either malononitrile ( 3a ) or ethyl cyanoacetate ( 3b ) in ethanol containing a catalytic amount of triethylamine to give the 3,4,7,12b-tetrahydrochromeno[3,4-c]chromen-1-one derivatives 5a , b . The latter compounds underwent Gewald's thiophene synthesis through the reaction with either malononitrile or ethyl cyanoacetate to give compounds 6a-d , respectively. On the other hand, compound 5a was used for the synthesis of annulated chromeno[3,4-c]chromen derivatives through its reaction with different chemical reagents. The synthesized compounds were evaluated against the six cancer cell lines A549, HT-29, MKN-45, U87MG, SMMC-7721, and H460 using the standard MTT assay in vitro, with foretinib as the positive control, many compounds expressed high inhibitions. The most active compounds 5b , 6b , 6d , 7 , 9b , 11a , 11b , 13 , 17 , 18b , 20b , 21b , 21e , and 21f were selected for inhibition of five tyrosine kinases and some selected compounds for Pim-1 kinase inhibition. The results showed that compounds 6b , 6d , 11a , 13 , 17 , 20b , and 21e were the most potent compounds with the tyrosine kinases and compounds 6d , 11a , 20b , and 21e were the most potent inhibitors of Pim-1 kinase.     

Enhancing foam stability in porous media by applying nanoparticles

Several new foaming agent formulations (surfactants and polymers) in the presence of multi-walled carbon nanotube (MWCNT) were developed in 3% salinity (NaCl, 2.4?wt%, CaCl₂, 0.6?wt%). The dispersion stability of the MWCNT and the viscosity of the solutions were examined as a prerequisite for reservoir applications. Foam was generated in situ and one-dimensional flow-through tests were performed by co-injecting air and foaming solution either in the presence of MWCNT or at particle-free condition. The pressure drop (Δp) across the sand-pack and the nanoparticles breakthrough were closely monitored. The fluid injection rate, gas fraction, and the effect of MWCNT on foams in porous media were investigated.

Our results reveal that foams stabilized by the selected nanoparticles are capable of generating stronger foams leading to higher apparent Δp. The Δp profile varies with gas fraction, which largely affects the foam texture and quality. Also, the viscosity of foaming agent solutions influences Δp values. Adding MWCNT to the foaming agent solutions appears beneficial to the flooding as surfactants adsorption onto nanoparticle surfaces, which facilitates surfactants partitioning to the G/L interface.

Addition of nanoparticles in the developed foam formulations leads to the formation of high-quality stronger foams in porous media, which could potentially improve the sweep efficiency and increase the oil recovery.     

Quantitative structure–activity relationship model for prediction study of corrosion inhibition efficiency using two‐stage sparse multiple linear regression

A new quantitative structure–activity relationship (QSAR) of the inhibition of mild steel corrosion in 1 M hydrochloric acid using furan derivatives was developed by proposing two‐stage sparse multiple linear regression. The sparse multiple linear regression using ridge penalty and sparse multiple linear regression using elastic net (SMLRE) were used to develop the QSAR model. The results show that the SMLRE‐based model possesses high predictive power compared with sparse multiple linear regression using ridge penalty‐based model according to the mean‐squared errors for both training and test datasets, leave‐one‐out internal validation (Q²_int = 0.98), and external validation (Q²_ext = 0.95). In addition, the results of applicability domain assessment using the leverage approach reveal a reliable and robust SMLRE‐based model. In conclusion, the developed QSAR model using SMLRE can be efficiently used in the studies of corrosion inhibition efficiency. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis,characterization, anti-fungi and anti-bacterial activity of new [(2-pyridyl)-3-isatin]-bishydrazone

New [(pyridine-2-carboxaldhyde)-3-isatin]-bishydrazone (cpish), [(2-acetylpyridine)-3-isatin]-bishydrazone (apish), and [(2-benzoyl pyridine)-3-isatin]-bishydrazone (bpish) have been synthesized and characterized by the elemental analysis, IR, NMR and electronic spectra. The bioefficiency of the [(2-pyridyl)-3-isatin]-bishydrazones have been examined for their in-vitro antibacterial and antifungal activity against many types of bacteria and fungal cultures which are common contaminants of the environment in Egypt and some of which are involved in human and animal diseases or in plant diseases or frequently reported from contaminated soil, water, and food substances. The results of these studies indicate that the [(2-pyridyl)-3-isatin]-bishydrazones possess notable antimicrobial properties.     

A Review of Human Coronaviruses’ Receptors: The Host-Cell Targets for the Crown Bearing Viruses

A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors.     

Dust ion‐acoustic solitons collision in weakly relativistic plasmas with superthermality‐distributed electrons and positrons: Higher‐order phase shifts

The higher‐order (H‐O) phase shift of dust ion‐acoustic solitons (DIASs) in a weakly relativistic plasma is examined considering the influence of both superthermality‐distributed electrons and positrons. Employing the extended Poincaré–Lighthill–Kuo method (EPLKM), the Korteweg–de Vries equations (KdVEs) and the deviation in trajectories of DIASs (i.e., phase shifts) are obtained after the collision. For obtaining H‐O phase shifts of DIASs, the fifth‐order dispersion terms are added into KdVEs. The effects of the relativistic factor for a weakly relativistic regime and the superthermality of both electrons and positrons on the H‐O phase shifts are discussed. Numerical analysis gives rise to important highlights on the excitation and the collision of DIASs in astrophysical situations such as a pulsar magnetosphere.