Chromene is considered a fused pyran ring with a benzene ring, which is found in many plants and is part of many important compounds such as anthocyanidins, anthocyanins, catechins, and flavanones. These compounds are included under the headings "flavonoids" and "iso-flavonoids." These compounds are well known as bioactive molecules with wide medicinal uses. According to these pharmacokinetic characteristics, many researchers are giving more attention to this type of compound and its derivatives. Many chromene derivatives have been synthesized to study their biological effects for the treatment of many diseases. Furthermore, the researcher displayed wide interest in finding new methods for synthesizing chromene derivatives. These methods depend on utilizing a new catalyst to increase the yield of this reaction or reduce the time of the reaction. On the other hand, new methods were found by using a new reactant and a new substrate. This review will present the most recent important methods for the synthesis of chromene derivatives as well as an examination of their biological activity.
Nanocrystalline aluminophosphate AlPO4-5 molecular sieves were synthesized by hydrothermal method (HTS). Synthesis parameters like time and temperature of crystallization were investigated. Type of template (R) and ratio of R/P2O5 were studied also. Characterization of the synthesized AlPO4-5 were done by powder X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), Fourier transform infrared (FTIR), differential scanning calorimetry-thermogravimetry analysis (DSC-TGA), and N2 adsorption-desorption BET analysis. XRD patterns results showed excellent crystallinity for two types of templates, di-n-propylamine (DPA) and tetrapropyl ammonium hydroxide (TPAOH) f
... Show MoreFour new phenol-formaldehyde resins containing tetrachlorophthalimides in their repeating units were synthesized via condensation of formaldehyde with N-(hydroxy phenyl)tetrachlorophthalimides under conditions similar to those used in novolac preparation. In this work structural modifications were performed first via design and synthesis of new phenolic component represented by phenolic ring linked to thermally stable tetrachlorophthalimide moiety which condense with formaldehyde and second via introducing of phenolic hydroxyl groups present in the new synthesized resins by esterification reaction with acetyl chloride producing the corresponding acetoxy substituted resins. Both the prepared and the cured resins have new properties which
... Show MoreIn this work, new di-acid monomers 4, 4’-di-carboxillic-4â€-bromo-2â€, 6â€-dimethyl triphenylamine (Ma), 4, 4’- di-carboxylic -4â€-chloro-2â€, 6â€-dimethyl triphenylamine (Mb) and 4, 4’- di-carboxylic -2â€,4â€-dichloro-6â€-methyl triphenylamine (Mc) were synthesized by reaction of p-cyanobenzofluride with three different aromatic amines (4-bromo,2,6-dimethyl aniline, 4-chloro,2,6-dimethyl aniline and 2,4 dichloro, 6- methyl aniline ) via aromatic nucleophilc substitution method to form three di cyano intermediates 4, 4’-Dicyano-4â€-bromo-2â€, 6â€-dimethyl triphenylamine (Da), 4,
... Show MoreBromelain is a proteolytic enzyme rich in cysteine proteases, extracted from the stem and fruit of pineapple (Ananas comosus). There are several therapeutic applications of the bromelain enzyme, where it has anti-inflammatory, anti-cancer, and antimicrobial activity, reduces joint pain, and accelerates wound healing. In the current study, bromelain enzyme was loaded on silver nanoparticles (Br-AgNPs) prepared using the citrate-reduction Turkevich method. Different characterization analyses were performed, including UV-Vis spectrophotometers, FTIR, SEM, and XRD analyses. Moreover, the antioxidant activity of prepared Br-AgNPs was evaluated by DPPH assay. The results of UV-Vis showed a peak at 434 nm, which referred to the AgNPs f
... Show MoreThe new Schiff base 1‐[(2‐{1‐[(dicyclohexylamino)‐methyl]‐1H‐indol‐3‐yl}‐ethylimino)‐methyl]naphthalen‐2‐ol (HL) was prepared from 1‐{[2‐(1H‐Indol‐3‐yl)‐ethylimino] methyl}‐naphthalen‐2‐ol and dicyclohexyl amine. From this Schiff base, monomeric complexes [M (L)n (H2O)2 Cl2] with M = Cr, Fe, Mn, Cd, and Hg were synthesized and characterized based on elemental analysis (EA), FT‐IR, mass(MS), UV‐visible, thermal analysis, magnetic moment, and molar conductance. The results showed that the geometrical structural were octahedral geometries for the Cr(III) and Fe(III) complex
Polypyrrole (PPy) nanocomposites were prepared using chemical oxidation and were combined with manganese oxide (MnO2) nanoparticles. The PPY-MnO2 nanocomposite was synthesized by integrating PPy nanofibers with varying volume ratio percentages of MnO2 dopant (10, 30, and 50% vol. ratio). The structural features of the PPy and PPy-MnO2 nanocomposite were investigated using X-ray diffraction (XRD). Fourier transfor infrared (FTIR) spectroscopy was used to demonstrate the molecular structures of primary materials and the final product of PPy, MnO2, and PPy- MnO2 nanocomposites. Field Emission Scanning Electron Microscopy (FESEM) showed that the morphology of PPy consisted of a network of nanofibers. Increasing the volume ratios of ma
... Show Moreهدفت هذه الد ا رسة لاختبار تاثير بعض ظروف النمو على الفاعلية التثبيطية لبكتيريا Lactobacillus delbrueckii و L.fermentum على نمو بكتيريا E.coli وقد دلت نتائج د ا رسة اختبار الفاعلية التثبيطية
للعزلتان البكتيريتان Lactobacillus delbrueckii L.fermentum , ضد العزلة البكترية E.coli المستخدمة في هذه الد ا رسة عند الت ا ركيز المختلفة 100,90,70,50) ( % بان عالق العزلتان البكتيريتان
Lactobacillus delbrueckii و L.fermentum عند التركيز % 100 اعطى اعلى فاعلية تثبيطية ضد
بكتريا E.coli
In this research study, I tried to trace the epic effect to learn how it was understood and how it was used. Following the descriptive and analytical approach in the research, the first chapter dealt with a presentation of the methodological framework of the problem, the goal, the limits of the research, the importance and the need for it and the definition of terms, as well as the theoretical framework which consisted of two topics, including the impact of the epic theater on the world theater and the second the effect of the epic theater on the Arab theater, This came by tracing the epic impact on the world stage of the Greeks, the Middle Ages, the Renaissance, and the Arab theater of the twentieth century.
As for the second
The structural properties of the CuO nanopowder oxide prepared reflux technique
without any templates or surfactant, using copper nitrate hydrate (Cu(NO)3 3H2O) in deionized
water with aqueous ammonia solution are reported. The Xrd analysis data and processing in origin
pro program used to get FWHM and integral width to study the effect of different synthesis times
was studied on the structural properties. It was found that values of crystal sizes are 17.274nm,
17.746nm, and 18.560nm, the size of nanoparticles is determined by Halder-Wagner, and 15.796
nm, 15.851nm, and 16.52nm, were calculated by Size-Strain Plot (SSP) method. The Sample was
considered to determine physical and microstructural paramete