In vitro cytotoxic evaluation of some new heterocyclic sulfonamide derivatives

Sulfonamide‐bearing compounds posses many types of biological activities and have been recently reported to show substantial antitumor activity in vitro and/or in vivo. There are a variety of mechanisms for the anticancer activity, and the most prominent mechanism is the inhibition of carbonic anhydrase isozymes. This work reports the synthesis of some new quinoline, pyrimido[4,5‐b]quinoline and 3,1‐oxazinoquinoline derivatives bearing a sulfonamide moiety. All the newly synthesized compounds were evaluated for their in vitro anticancer activity against Ehrlich ascites carcinoma cells. Compounds 10 , 13 , and 26 were the most active compounds with IC₅₀ values of 6.1 μM, 6.8 μM, and 6.4 μM, respectively, and exhibited better activities than the reference drug doxorubicin (IC₅₀ = 68.1 μM). J. Heterocyclic Chem., 2011.     

The impact of protonation and deprotonation of 3-methyl-2'-deoxyadenosine on N-glycosidic bond cleavage

The enzyme-substrate contacts that are believed to be involved in depurination by proton transfer have been modelled by protonation and deprotonation of 3-methyl-2'-deoxyadenosine (3-MDA) using quantum mechanical calculations in the gas-phase and solution media. The change in the charge distribution on the sugar ring and nucleobase that is introduced by the protonation and deprotonation strongly affects the N-glycosidic bond length. The unimolecular cleavage and hydrolysis of the N-glycosidic bond, involving D(N)*A(N) and A(N)D(N) pathways, have been considered at several levels of theory. The trend in the energy barriers is A(N)D(N) > cleavage > D(N)*A(N). All probable proton transfer reactions resulting from enzyme-substrate contacts do not facilitate the N-glycosidic bond cleavage of 3-MDA. The deprotonation of 3-MDA that may result from the interaction between H6 and enzyme do not facilitate bond cleavage. The protonation at N7 induces more positive charge on the sugar ring and further facilitates the depurination relative to the protonation at N1. The changes in the charges calculated on the ribose and nucleobase are in good relationship with the C1'-C2', C1'-O4', and N-glycosidic bond lengths along the cleavage. The change in energy barrier ΔE of glycosidic bond cleavage from the gas-phase to solution media strongly depends on the charge of the species.     

A collocation method of lines for two‐sided space‐fractional advection‐diffusion equations with variable coefficients

We present the method of lines (MOL), which is based on the spectral collocation method, to solve space‐fractional advection‐diffusion equations (SFADEs) on a finite domain with variable coefficients. We focus on the cases in which the SFADEs consist of both left‐ and right‐sided fractional derivatives. To do so, we begin by introducing a new set of basis functions with some interesting features. The MOL, together with the spectral collocation method based on the new basis functions, are successfully applied to the SFADEs. Finally, four numerical examples, including benchmark problems and a problem with discontinuous advection and diffusion coefficients, are provided to illustrate the efficiency and exponentially accuracy of the proposed method.     

Comparison between standard and counterpoise-corrected optimization using some hydrogen and halogen bonded systems

The effect of the counterpoise correction on the geometries, stabilization energies, and vibrational harmonic frequencies of some hydrogen- and halogen-bonded systems (B?=?CH₃CN,?HCN,?NH₃,?N₂,?CO,?H₂O,?H₂S,?PH₃;?HX?=?HF,?HCl,?HBr,?HCN,?HCF₃; XY?=?Br₂,?BrCl,?BrF,?Cl₂,?ClF,?F₂) has been analysed at the MP2 level of theory using the popular 6-311++G(d,p) basis set. The optimized B?···?H and B?···?X bond lengths increase with counterpoise (CP) correction. In some cases standard values and in other cases CP-corrected values are close to experimental data. The absolute values of complexation energies of CP-corrected structures are higher than standard by inclusion of BSSE correction. The effect of CP correction on intermolecular bond lengths and complexation energies of B?···?XY series are usually higher than B?···?HX. Also, this effect is higher for H₂S and PH₃ groups. The CP correction changes the vibrational harmonic frequencies by 0–100%. The changes are frequently lower than 20% for frequencies higher than 300?cm^?1.     

Optimization of two parallel wires of laser plasma filaments for channeling electromagnetic energy

We theoretically investigated the electromagnetic wave (EMW) transmission along two parallel wires of laser plasma filaments produced by the filamentation of ultrafast laser pulses in air. Many factors, such as wire diameter and separation, electron density, and operating frequency are shown to influence the propagation loss. By taking into consideration the radiation and transmission effects of the wires, the calculations of the two parallel filament wires reasonably agrees with that of the standard commercial twin-lead wire. Specifically, the optimum separation of the two wires is determined for a given frequency and an effective electron density of the wires. When compared with free-space propagation, transmission enhancement of tens dB is obtained using optimized wire configurations. Thus, the two plasma wires may be a potential channel for point to point directed delivery of EM energy or communication of pulsed-modulated EM radiation.     

Chemometric Assisted UV-Spectrophotometric Methods Using Multivariate Curve Resolution Alternating Least Squares and Partial Least Squares Regression for Determination of Beta-Antagonists in Formulated Products: Evaluation of the Ecological Impact

In this study, UV-spectrophotometry coupled with chemometrics has been utilized to enhance the sustainability of quality control analysis of beta antagonists. First, we developed and optimized two eco-friendly chemometric-assisted methods without preliminary separation utilizing (1) multivariate curve resolution alternating least squares (MCR-ALS) and (2) well-established partial least squares regression (PLSR) multivariate calibration for the resolution and quantification of the most commonly prescribed beta antagonists in active pharmaceutical ingredients or commercial pharmaceutical products. The performance of the two proposed chemometric methods was computed and compared. Second, a comprehensive qualitative and quantitative evaluation of the eco-friendliness of the developed methods was performed utilizing the following greenness assessment tools: Green Analytical Procedure Index (GAPI), Analytical Eco-scale assessment (AES) tool, Raynie and Driver’s assessment tool and Analytical GREEnness Metric (AGREE). The models showed satisfactory recovery with a range from 99.83% to 101.12% for MCR-ALS and from 99.66% to 101.54% for PLSR. The optimized models were employed for green analysis of the investigated beta-blockers in single or co-formulated formulations without prior separation. The predictivity of the proposed MCR-ALS and the well-established PLSR method were very comparable. Nevertheless, the MCR-ALS method has the ability to recover the pure spectra of the studied analytes and the interferences as well. The proposed chemometric methods are fast, precise and do not need any sample pretreatment. In addition, they can be used as a benign substitute for the traditional methods used for the analysis of the investigated drugs in pharmaceutical products without harmful impacts on human health and the environment. They also provide advantages in terms of low solvent usage, reduced energy consumption and short analysis time, making them a safe and sustainable approach for quality control analysis.     

Oil-in-Water Nanoemulsion Can Modulate the Fermentation,Fatty Acid Accumulation,and the Microbial Population in Rumen Batch Cultures

In this study, three oil-in-water nanoemulsions were tested in two stages: In the first stage, three levels (on the substrate dry matter (DM)), namely 3%, 6%, and 9%, of three different oils, olive oil (OO), corn oil (CO), and linseed oil (LO), in raw and nanoemulsified (N) forms were used separately in three consecutive rumen batch cultures trials. The second stage, which was based on the first stage’s results, consisted of a batch culture trial that compared the raw and nanoemulsified (N) forms of all three oils together, provided at 3% of the DM. In the first stage, NOO, NCO, and NLO preserved higher unsaturated fatty acid (UFA) and less saturated fatty acid (SFA) compared to OO, CO, and LO, respectively; noticeably, NCO had UFA:SFA = 1.01, 1.16, and 1.34 compared to CO, which had UFA:SFA = 0.66, 0.69, and 0.72 when supplemented at 3%, 6%, 9% of DM, respectively. In the second stage, UFA:SFA = 1.04, 1.12, and 1.07 for NOO, NCO, NLO, as compared to UFA:SFA = 0.69, 0.68, and 0.72 for OO, CO, and LO supplemented at 3% of DM. In conclusion, oil-in-water nanoemulsions showed an ability to decrease the transformation of UFA to SFA in the biohydrogenation environment without affecting the rumen microorganisms.     

Thermal conductivity modeling of nanofluids with ZnO particles by using approaches based on artificial neural network and MARS

Journal of Thermal Analysis and Calorimetry - Nanofluids are attractive alternatives for the current heat transfer fluids due to their remarkably higher thermal conductivity which leads to the...     

Comprehensive Metabolite Profiling in Genetic Resources of Garlic (Allium sativum L.) Collected from Different Geographical Regions

Garlic (Allium sativum) is the second most important Allium crop that has been used as a vegetable and condiment from ancient times due to its characteristic flavor and taste. Although garlic is a sterile plant that reproduces vegetatively through cloves, garlic shows high biodiversity, as well as phenotypic plasticity and environmental adaptation capacity. To determine the possible mechanism underlying this phenomenon and to provide new genetic materials for the development of a novel garlic cultivar with useful agronomic traits, the metabolic profiles in the leaf tissue of 30 garlic accessions collected from different geographical regions, with a special focus on the Asian region, were investigated using LC/MS. In addition, the total saponin and fructan contents in the roots and cloves of the investigated garlic accessions were also evaluated. Total saponin and fructan contents did not separate the garlic accessions based on their geographical origin, implying that saponin and fructan contents were clone-specific and agroclimatic changes have affected the quantitative and qualitative levels of saponins in garlic over a long history of cultivation. Principal component analysis (PCA) and dendrogram clustering of the LC/MS-based metabolite profiling showed two major clusters. Specifically, many Japanese and Central Asia accessions were grouped in cluster I and showed high accumulations of flavonol glucosides, alliin, and methiin. On the other hand, garlic accessions grouped in cluster II exhibited a high accumulation of anthocyanin glucosides and amino acids. Although most of the accessions were not separated based on country of origin, the Central Asia accessions were clustered in one group, implying that these accessions exhibited distinct metabolic profiles. The present study provides useful information that can be used for germplasm selection and the development of new garlic varieties with beneficial biotic and abiotic stress-adaptive traits.     

Investigation and comparison of biological effects of regioselectively synthesized thiazole derivatives

In this study, anticancer, antibacterial (against hospital-isolated antibiotic-resistant Escherichia coli strains), antifungal, and antioxidant effects of synthesized heterocyclic compounds 5 and 7 containing thiazole core were examined. Cytotoxicity testing was utilized against MCF-7 breast cancer cells via MTT cell viability assay. Antibacterial and antifungal activities were checked out according to Clinical and Laboratory Standards Institute (CLSI) guidelines, and antioxidant properties were evaluated through scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals. Results showed the viability of breast cancer cell lines was reliant on concentration of heterocycles and time of incubation. Synthetic compounds exhibited excellent antibacterial and antifungal properties base on their minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) values as well as high antioxidant activities according to their IC₅₀ values. Higher anticancer and antibacterial properties were observed with compound 7; on the contrary, thiazole 5 had better antioxidant effects. They can be introduced as potent antimicrobial, antioxidant, and anticancer agents.