667 research outputs found

    Síntesis y evaluación de algunos agentes surfactantes de aminas grasas de cadena larga

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    This study continues our series of synthesis of surface active agents containing heterocyclic moiety. NHeptadecanoyl- 3-(4-oxo-4H-benzo[d][1,3]oxazin-2-yl)- acrylamide (4) was used as a new starting material to synthesize propenoxylated nonionic surface active agents having heterocycles such as (thiazole, triazole, benzoxazine, quinazoline, triazine, and oxazine). The structures of the prepared compounds were elucidated by using spectroscopic tools (IR, 1H NMR and Mass spectroscopy). Physical properties such as surface and interfacial tension, cloud point, foaming height, wetting time, emulsification power and critical micelle concentration (CMC) were determined. Antimicrobial and biodegradability properties were also screened. It was found that the produced novel groups of nonionic surface active agents have pronounced surface properties and good antimicrobial activities.Este estudio continua nuestra serie sobre la síntesis de agentes surfactantes que contienen grupos heterociclicos. N-Heptadecanoyl-3-(4-oxo-4H-benzo[d][1,3]oxazin-2-yl)- acrylamida (4) se usa como nueva materia prima para sintetizar surfactantes noiónico propenoxilado conteniendo herociclos tales como thiazol, triazol, benzoxazina, quinazolina, triazina, y oxazina. Las estructuras de los compuestos preparados se dilucidan mediante herramientas espectroscópicas (IR, 1H NMR and espectroscopía de masas). Se determinan sus propiedades físicas, tensión superficial e interfacial, punto de nube, altura de espuma, poder de emulsificación y concentración micelar critica.También se revisan sus propiedades antimicrobianas y de biodegradabilidad Se encontró que los nuevos compuestos poseían destacadas propiedades superficiales y unas buenas actividades antimicrobianas

    Síntesis y evaluación de compuestos heterocíclicos derivados de ?-hidroxiácidos con interés industrial potencial.

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    The reaction of 2-hydroxyheptadecanoyl chloride (2) and anthranilic acid gave 2-(1-hydroxyheptadecyl)-4H-3,1-benzoxazin-4-one (3) which was used as starting material to synthesize some condensed and non-condensed heterocyclic compounds by a reaction with nitrogen nucleophiles (e.g., hydrazine hydrate, and formamide). The subsequent reaction of the synthetic products with different amounts of propylene oxide gave a novel group of nonionic compounds having a double function as antibacterial and surface active agents which may serve in the manufacturing of drugs, cosmetics, pesticides or as antibacterial and/or antifungal products. The surface active properties such as surface and interfacial tensions, cloud point, foaming height, wetting time, and emulsification power were determined. Antimicrobial and biodegradability were also screened.La reacción de cloruro de 2-hidroxiheptadecanoilo (2) con ácido antranílico produjo 2-(1-hidroxiheptadecil)-4H-3,1-benzoxazin-4-ona (3) que fue usada como material de partida en la síntesis de compuestos heterocíclicos condensados y no condensados por reacción con nucleófilos nitrogenados (hidracina y formamida). La reacción de los productos sintetizados con distintas cantidades de óxido de propileno dio un grupo nuevo de compuestos no iónicos con una función doble como antibacterianos y agentes tensioactivos que pueden servir en la manufactura de medicamentos, cosméticos, pesticidas, o como productos antibacterianos y/o antifúngicos. Se determinaron las propiedades tensioactivas así como la capacidad antimicrobiana y la biodegrabilidad de los compuestos sintetizados

    Tensioactivos anfóteros conteniendo un grupo alfa hidroxi éster y un residuo de aminoácido

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    A series of amphoteric surfactants containing α-hydroxy ester group and an amino acid residue were prepared with the addition of epoxy derivatives (which were prepared from epoxidation of alkyl methacrylate) to different types of amino acids (glycine, alanine, valine, isoleucine, phenylalanine, tyrosine, serine, threonine, aspartic and anthranilic acid).The structures of the prepared compounds were confirmed by infrared spectra, proton magnetic resonance spectra, Mass spectra and elementary analysis. Surface tension, Kraft point, foaming power, critical micelle concentration emulsion and Ca++ stabilities were determined. Antimicrobial activity and biodegradability were also screened.Se prepararon una serie de tensioactivos anfóteros conteniendo un grupo alfa hidroxi éster y un residuo de aminoácido por adición de derivados epoxy (obtenidos mediante epoxidación de metacrilato de alquilo) a diferentes tipos de aminoácidos (glicina, alanina, valina, isoleucina, fenilalanina, tirosina, serina, treonina y ácidos aspártico y antranílico). Las estructuras de los compuestos preparados se confirmaron por los espectros de infrarrojo, de masa, resonancia magnética nuclear de protones y análisis elemental. Se determinaron la tensión superficial, el punto de Kraft, el poder espumante, la concentración micelar crítica en emulsión y las estabilidades de Ca++. También se estudiaron la actividad antimicrobiana y la biodegradabilidad

    Amphoteric surface active agents

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    ENHANCEMENT OF LORNOXICAM SOLUBILITY BY INCLUSION COMPLEXATION WITH CYCLODEXTRIN: PREPARATION AND CHARACTERIZATION

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    Objective: Lornoxicam is a potent anti-inflammatory drug which has analgesic and antipyretic properties. It is water-insoluble powder. The inclusion complexes of lornoxicam (LOR) with β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPCD) were prepared and characterised in order to improve the solubility of the drug and enhance its bioavailability.Methods: Complexes were prepared by physical mixing and freeze-drying in three different drug/polymer ratios (1:1, 1:2 and 3:2). The solid complexes were characterised through differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffraction, nuclear magnetic resonance (NMR) spectroscopy, and Fourier transformed infrared (FTIR) spectroscopy.Results: The data showed that LOR may be complexed with cyclodextrin (CD) forming soluble complexes. The lyophilized 1:2 LOR/HPCD complex is the most soluble.Conclusion: Solubility increases with lyophilization than with physical mixing and by the use of HPCD than βCD in complexation

    Genetic Algorithm Optimization Model for Determining the Probability of Failure on Demand of the Safety Instrumented System

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    A more accurate determination for the Probability of Failure on Demand (PFD) of the Safety Instrumented System (SIS) contributes to more SIS realiability, thereby ensuring more safety and lower cost. IEC 61508 and ISA TR.84.02 provide the PFD detemination formulas. However, these formulas suffer from an uncertaity issue due to the inclusion of uncertainty sources, which, including high redundant systems architectures, cannot be assessed, have perfect proof test assumption, and are neglegted in partial stroke testing (PST) of impact on the system PFD. On the other hand, determining the values of PFD variables to achieve the target risk reduction involves daunting efforts and consumes time. This paper proposes a new approach for system PFD determination and PFD variables optimization that contributes to reduce the uncertainty problem. A higher redundant system can be assessed by generalizing the PFD formula into KooN architecture without neglecting the diagnostic coverage factor (DC) and common cause failures (CCF). In order to simulate the proof test effectiveness, the Proof Test Coverage (PTC) factor has been incorporated into the formula. Additionally, the system PFD value has been improved by incorporating PST for the final control element into the formula. The new developed formula is modelled using the Genetic Algorithm (GA) artificial technique. The GA model saves time and effort to examine system PFD and estimate near optimal values for PFD variables. The proposed model has been applicated on SIS design for crude oil test separator using MATLAB. The comparison between the proposed model and PFD formulas provided by IEC 61508 and ISA TR.84.02 showed that the proposed GA model can assess any system structure and simulate industrial reality. Furthermore, the cost and associated implementation testing activities are reduced

    Monitoring of multi-class pesticide residues in green grape and their potential risk for Egyptian consumer

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    Abstract: The residual concentrations of 100 pesticides in 32 fresh grape samples collected from local markets at eight Egyptian governorates during 2011' summer season were monitored based on QuEChERS extraction followed by analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatographytandem mass spectrometry (GC-MS/MS). The potential health risks associated with the exposure to violated pesticides were estimated as well. Mean recoveries ranged between 71 and 96.3%, while the repeatability expressed as relative standard deviation (RSD) was < 19.8%. Limits of quantification (LOQ) was 0.01 mg kg -1 , which is equal or below the Maximum Residue Limits (MRLs). Of the analysed samples, 81.25% contained detectable residues, of which 21.88% exceeded their MRLs. Out of 35 pesticides that were detected in grape samples, carbendazim, acetamiprid, boscalid, λ-cyhalothrin, profenofos and pyraclostrobin were the most frequently pesticides detected. No residues of organochlorine pesticides and their metabolites were detected in any analysed samples. This study showed also that the estimated daily intake (EDI) of the violated pesticides by the Egyptian population through the consumption of grape did not exceed the toxicological acceptable level

    Síntesis y evaluación de compuestos heterocíclicos derivados de ?-hidroxi ácidos grasos con interés industrial potencial

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    T2-Hydroxyheptadecanoic acid chloride (2) reacted with anthranilic acid to produce 2-substituted-3,1-benzoxazin-4-one (3) which was used as starting material to synthesize some condensed and non-condensed heterocyclic compounds by reaction with nitrogen nucleophiles e.g., hydrazine hydrate, and formamide. The products were subjected to reaction with different moles of propylene oxide (n = 5, 10, 15) to produce a novel group of nonionic compounds having a double function as antibacterial and surface active agents which can be used in the manufacturing of drugs, cosmetics, pesticides or can be used as antibacterial and/or antifungal additives. The surface active properties as surface and interfacial tension, cloud point, foaming height, wetting time, and emulsification power were determined, the antimicrobial and biodegradability were also screened.El cloruro del ácido 2-hidroxiheptadecanoico (2) reaccionó con el ácido antranílico para producir 3,1-benzoxazin-4-onas 2-sustituidas que fueron usadas como material de partida en la síntesis de compuestos heterocíclicos condensados y no condensados por reacción con nucleófilos nitrogenados, como la hidracina o la formamida. Los productos fueron hechos reaccionar con diferentes moles de óxido de propileno (n = 5, 10, 15) para producir un grupo nuevo de compuestos no-iónicos teniendo una doble función como antibacterianos y tensoactivos que pueden ser usados en la manufactura de medicamentos, cosméticos, pesticidas, o pueden ser usados como aditivos antibacterianos y/o antifúngicos. Se determinaron diversas propiedades físicas de los compuestos preparados así como sus efectos antimicrobianos y sus biodegrabilidad

    Synthesis and Reactivity of 6-Iodo-4H-3,1-Benzoxazin-4-one Towards Nitrogen Nucleophiles and Their Antimicrobial Activities

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    In attempt to find new pharmacological active molecules, we synthesized 6-iodo-4H-3,1-benzoxazin-4-one and allowed it to react with some nitrogen nucleophiles namely; hydroxylamine hydrochloride, hydrazine hydrate, fomamide, aliphatic amine, aromatic amines, aralkyl amine, different amino acids, heteryl amines, ethanolamine and sodium azide to afford annelated quinazolinone derivatives and other related systems. The synthesized compounds were characterized with the help of spectroscopic techniques including IR, 1H-NMR and Mass spectra. Also their antimicrobial activities were screened against different strains of bacteria and fungi. Keywords: 6-Iodo-4H-3,1-benzoxazin-4-one; quinazolinone derivatives;  nitrogen nucleophiles; antimicrobial activity
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