Efficient synthesis,reactions, and biological activities of new thieno and furopyrazolo[3,4-b]pyrazines and their related heterocycles

In the present investigation, a simple and straightforward methodology for the preparation of novel bifunctional thienopyrazolopyrazines 4a–d has been reported. Synthesis of thieno or furopyrazolopyrazines 5a , b , e , f was achieved by the reaction of o-amino-esters 4a , b , e , f with 2,5-dimethoxytetrahydrofuran. The latter pyrrolyl derivatives 5a , b , e , f were used as starting intermediates for the synthesis of new pyrimido, pyrido, and pyrazino heterocycles fused to the thieno or furopyrazolopyrazine moiety. Furthermore, alkaline hydrolysis of the o-amino-ester 4a followed by acidification afforded the corresponding o-amino carboxylic acid 15 , which was used as a versatile precursor for the synthesis of other heterocyclic compounds fused to the thienopyrazolopyrazine ring system, namely: pyrimidine, oxazine, oxazepine, and pyridine derivatives 16–23 . The chemical structures of the synthesized compounds were confirmed on the basis of elemental and spectral analyses (Fourier-transform infrared spectroscopy [FT-IR], ¹H nuclear magnetic resonance [NMR], and mass spectroscopy [MS] in addition to ¹³C NMR for some of them). Moreover, from the biological screening, we found that most of the tested compounds exhibited promising antifungal, antibacterial, and anti-inflammatory activities compared with the corresponding reference drugs.     

Restoration of IP Networks by Using a Hybrid Interacting Mechanism Between Layer 2 & 3 in the Networks Over OA&M

The Internet generation infrastructure is growing and moving towards a consistency model of high-speed nodes interconnected by optical core networks. Therefore, the interaction between IP and optical network layers, specifically, the routing and signalling aspects, are maturing and they can lead to enhance the services and network performance. At the same time, a consensus has emerged in the industry on utilizing IP-based protocols for the optical control plane. This paper defines a new technique for IP over Optical networks (interacting between bottom layers), considering both the IP-based control plane for optical networks as well as IP-optical network interactions (together referred to as “IP over optical networks”). In this paper, a new technique is proposed that reduces recovery time by making an interoperation between the data link layer (layer 2) with the network layer (layer 3). The proposed technique enables layer 2 with layer 3 to make a hybrid mechanism that improves the recovery time in the network through two cases (1st-Detection and 2nd-Rerouting). The technique involves detecting failure in less time through layer 2 and rerouting traffic through an alternative path between source and destination by using a new algorithm in layer 3 to deliver data packets without the need to wait for the routing protocol to update the network topology and compute the routing table. In case of the network recovery, layer 2 has demonstrated its capability to detect failure extremely quickly shown through the immediate detection of the loss of signals for the link or node. The recovery mechanism, i.e., the rerouting mechanism, which leads the node, switches the data packets through an adjacent node to its destination via the life node. The latter is created by the proposed mechanism before the occurrence of the failure. The aim of this mechanism is to avoid loss of packets, improve QoS and improve recovery time as we have shown in the results shown below.     

Antitumor,cytotoxic, and antioxidant evaluation of six heterocyclic compounds containing different heterocycle moieties

Heterocyclic compounds with different heterocycle moieties, namely benzoxazinone, benzimidazole, quinazolinone, and benzofuranone heterocyclic rings, were synthesized, characterized, and evaluated for their anticancer activity against human hepatocellular carcinoma cell line (HepG2) using sulforhodamine B (SRB) and dimethylthiazol-diphenyltetrazolium bromide (MTT) assays. Also, their cytotoxic activities were tested against human epithelioid carcinoma (Hela) cell line in comparison with normal cell, amniotic epithelial (WISH) cell line, as an in vitro toxicity estimation model. The results showed clearly that 2-(2-benzyl-4-oxoquinazolin-3(4H)-yl)acetohydrazide 4 is the most potent antioxidant and anticancer agents. Although, 3-amino-2-benzylquinazolin-4(3H)-one 5 is less potent anticancer agent against Hela but it is more safe against normal cell (WISH).     

Proteomic Advances in Milk and Dairy Products

Proteomics is a new area of study that in recent decades has provided great advances in the field of medicine. However, its enormous potential for the study of proteomes makes it also applicable to other areas of science. Milk is a highly heterogeneous and complex fluid, where there are numerous genetic variants and isoforms with post-translational modifications (PTMs). Due to the vast number of proteins and peptides existing in its matrix, proteomics is presented as a powerful tool for the characterization of milk samples and their products. The technology developed to date for the separation and characterization of the milk proteome, such as two-dimensional gel electrophoresis (2DE) technology and especially mass spectrometry (MS) have allowed an exhaustive characterization of the proteins and peptides present in milk and dairy products with enormous applications in the industry for the control of fundamental parameters, such as microbiological safety, the guarantee of authenticity, or the control of the transformations carried out, aimed to increase the quality of the final product.     

γ irradiation effect on the polarization and resistance of Li-Co-Yb-ferrite

The effect of γ irradiation on some physical properties of rare earth ferrite of the general formula Li_0.5+zCo_z Yb_xFe_2.5−2z−xO₄, (z=0.1, x=0.00, 0.025, 0.050, … , 0.200) is discussed. The temperature dependence of the polarization and resistance is studied in the range (300 K≤T≤700 K) at different frequencies (10 kHz≤f≤1 MHz). The relaxation time and the activation energy have been calculated before and after irradiation with γ rays doses of 1 and 3 Mrad. A comparison was made between the ac resistance before and after irradiation for the samples with (0.0≤x≤0.2). The results after irradiation with 1 Mrad γ rays showed that the resistance at the critical concentration decreases from 800 to 25 kΩ at room temperature. Furthermore, with increasing temperature the resistance ranged from R≈130 kΩ at T≈310 K to R≈0.13 kΩ at T≈640 K. Thus, it is possible to improve the conductivity of this type of rare earth ferrite materials to be used in technological applications at room as well as at high temperature.     

On The Optimization of Fractional Order Low-Pass Filters

This paper presents three different optimization cases for normalized fractional order low-pass filters (LPFs) with numerical, circuit and experimental results. A multi-objective optimization technique is used for controlling some filter specifications, which are the transition bandwidth, the stop band frequency gain and the maximum allowable peak in the filter pass band. The extra degree of freedom provided by the fractional order parameter allows the full manipulation of the filter specifications to obtain the desired response required by any application. The proposed mathematical model is further applied to a case study of a practical second- generation current conveyor (CCII)-based fractional low-pass filter. Circuit simulations are performed for two different fractional order filters, with orders 1.6 and 3.6, with cutoff frequencies 200 and 500 Hz, respectively. Experimental results are also presented for LPF of 4.46 kHz cutoff frequency using a fabricated fractional capacitor of order 0.8, proving the validity of the proposed design approach.     

Selective phosphate sensing using copper monoamino-phthalocyanine functionalized acrylate polymer-based solid-state electrode for FIA of environmental waters

A novel solid-state selective sensor for mono-hydrogen phosphate (HPO₄)^?2 based on copper monoamino phthalocyanine (CuMAPc) ionophore covalently attached to poly (n-butyl acrylate) (PnBA) has been developed and potentiometrically evaluated. The all solid-state sensor was constructed by the application of a thin film of a polymer cocktail containing a CuMAPc–PBDA ionophore and benzyl-dimethylhexadecyl ammonium chloride (BDMHAC) as a lipophilic cationic additive onto a gold electrode pre-coated with the conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 14.31 % of CuMAPc-PnBA (ionophore II) exhibited a good selectivity for (HPO₄)^?2. The thus constructed sensor discriminated many anions, including F^?, Cl^?, Br^?, I^–, CH₃COO^?, NO₃ ^?, ClO₄ ^?, and SO₄ ^2?. The potentiometric response of the phosphate selective electrode was found to be independent of the pH of sample solution in the range 6–9. The sensor showed a Nernstian slope of ?29.8 ± 0.3 mV conc.^?1 decade^?1 with linear range of 4.0 × 10^?9–1.0 × 10^?2 mol L^?1 and detection limit of 1.0 × 10^?9 mol L^?1 at pH 8.0. The proposed phosphate sensor has been utilized as a detector for the flow injection potentiometric determination of phosphate in different water samples at the nanomolar concentration range.