Isomerisation with sodamide in liquid ammonia of the S-alkyldihydroanisoles (IV) containing unconj ugated double bonds gives the exocyclic conjugated dienes (VI) as the final product if R'Reduction by sodium and propan-2-01 in liquid ammonia of 3,4-dimethylanisole (VII) and of B-methoxy-1,2,3,4-tetrahydronaphthalene (IX), followed by similar isomerisation, gives the endocyclic dienes (VIII) and (X). The mechanisms involved are discussed.REDUCTION of alkylanisoles with sodium and ethanol in liquid ammonia gives chiefly dihydroanisoles containing unconjugated double bonds as the result of kinetically controlled reactions.l~~*~ In the presence of an alkali-metal amide in liquid ammonia, these dienes are converted into the more stable conjugated isomers, usually by turning of a double bond about the carbon atom bearing the methoxyl group. This has been shown 3 ~4 to be due to establishment of an equilibrium of the type shown below. Apart from their intrinsic interest, a study of such reactions is important in understanding the course of reductions by lithium and various amines, since such equilibrations are clearly involved and permit reduction to occur past the dihydro-stage.2 H 6 Because 2,5-dihydroanisole is converted into 2,3-dihydroanisole as above, it was expected that 2,5-dihydro-3-methylanisole (I) would give the homologue (11). In fact this is produced to some extent, as shown by the diene reaction with dimethyl acetylenedicarboxylate.6 However, it was noted 6 that if the isomerisation proceeded for a long time, and in particular if the ammonia evaporated, a different product was obtained. This has now been shown to be the exocyclic diene (111) and it has been found that the endocyclic diene (11) cannot be prepared by this method in a state of purity because its rate of isomerisation to the diene ( 111) is comparable with its rate of formation.The courses of these and analogous reactions were followed by means of ultraviolet spectra. The unreduced alkylanisoles have twin peaks,' A , ,

A silver nanoparticle (AgNP) is likely to provide an attractive object for combining a variety of biochemical properties with great therapeutic potential by using radiation. The present study explores the IC 50 value of chitosan-poly (vinyl alcohol) hydrogel (Cs/PVA) and Ag-doped chitosan-poly (vinyl alcohol) (Cs/PVA/Ag) nanocomposite in view of their anticancer application. The aim was to develop (Cs/PVA) based hydrogel synthesized by gamma radiation which could behave both as a nanoreactor for Ag nanoparticle with promising anticancer applications. The (Cs/PVA/Ag) nanocomposite was confirmed by FTIR (Fourier transform infrared) spectroscopy, XRD (X-ray diffraction) and EDX (energy dispersive X-ray) analysis. The anti-cancer activity of the prepared nanocomposites was demonstrated in human liver cancer cell line (HEPG2) and breast cancer cell lines (MCF7). It has significant effects against human liver cancer cell line HEPG2 compared to breast cancer cell line MCF7. Further quantitative analysis on the molecular and protein levels is still required to confirm the impact of chitosan on genotoxic effect before reaching a final conclusion and starting its biomedical application.

C HITOSAN/ Gelatin/2-(Dimethylamino) ethyl methacrylate (Cs/Gltn/PDMAEMA) hydrogel was synthesized by gamma irradiation for the expulsion of phosphate ions from wastewater. Chemical adjustment of the hydrogel with thiourea was performed to introduce thiol groups Cs/Gltn/PDMAEMA-treated. Moreover trapping of SiO 2 into the hydrogel matrix to acquire Cs/Gltn/PDMAEMA/SiO 2 composite. It was found that the gelation increases with increasing PDMAEMA content in the hydrogel. The maximum gelation performed at an equal ratio of Cs/Gltn at a radiation dose of 15 kGy. The adsorption capacities of the prepared systems towards phosphate ions were investigated. It was obtained that the maximum removal is achieved at pH 6 through 180 min. However, the removal percent decreases with increasing phosphate ions concentration and temperature. The ability of the prepared adsorbents towards phosphate ions removal are ascending ordered in the sequence of Cs/Gltn/PDMAEMA hydrogel, Cs/Gltn/PDMAEMA-treated , and Cs/Gltn/PDMAEMA/SiO 2 composite. The pseudo secondorder equation fits well the adsorption kinetics. The adsorption isotherm follows the Freundlich model higher than the Langmuir model

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Novel sensitive disposable sensors have been introduced for potentiometric determination of naproxen (NAP) based on single‐walled carbon nanotubes‐polyvinyl chloride (SWNTs‐PVC) composite incorporated of calix[4]arene as host‐guest molecular recognition element. The electrode matrix composition was optimized on the basis of the nature and content of the sensing element, cationic sites, plasticizer and nanomaterial. Remarkable selectivity and sensitivity towards NAP was achieved in the concentration range from 10−8 to 10−2 mol L−1 with anionic Nernstian compliance −61.0±0.0 mV decade−1. Modification with calixarene and carbon nanotubes improved the sensors performance through formation of NAP‐calixarene inclusion complex and promotion of the electron‐transfer processes which enhance the potential stability, response time, and shelf lifetime of the sensor. The proposed sensors were successfully applied for the potentiometric assay of NAP in dosage formulation and biological fluids under batch and flow injection analysis (FIA) conditions with average recoveries agreeable with the reported official methods.