RESUMEN
4-Hydroxycoumarins are some of the most versatile heterocyclic scaffolds and are frequently applied in the synthesis of various organic compounds. 4-Hydroxycoumarin-based compounds are important among heterocyclic structures due to their biological and pharmaceutical activities. In this study, we provide an overview on the recent applications of 4-hydroxycoumarin in multicomponent reactions for the synthesis of various heterocyclic compounds during the time period of 2015-2018.
Asunto(s)
4-Hidroxicumarinas/química , Piranos/química , Pirimidinas/química , Pirrolidinas/químicaRESUMEN
An isonicotinic acid hydrazide (INAH) chemically modified fumed silica, as a novel adsorbent, was designed for the preconcentration and determination of Hg (II) ions in fish samples via the solid phase extraction followed by the hydride generation atomic absorption spectrometry (HG-AAS). In this work, the efficiency of the synthesized adsorbent was investigated to determine its ability for the extraction of the Hg (II) ions from the aqueous solutions. The extraction efficiency was investigated by optimizing of different experimental conditions, such as pH, sample volume, flow rate, adsorbent dosage, and eluent type. Under the optimal conditions, a linear calibration curve for the solid phase extraction method was obtained in the range of between 0.12 and 16.5⯵gâ¯L-1. The obtained detection limit and preconcentration factor were 0.018⯵gâ¯L-1 and 25, respectively (RSDâ¯>â¯3%). The proposed optimized method was successfully applied to fish samples.
Asunto(s)
Productos Pesqueros/análisis , Mercurio/análisis , Nanopartículas/química , Extracción en Fase Sólida/métodos , Espectrofotometría Atómica/métodos , Adsorción , Animales , Contaminación de Alimentos/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Mercurio/aislamiento & purificación , Dióxido de Silicio/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificaciónRESUMEN
Indoles are some of the most versatile and common nitrogen-based heterocyclic scaffolds and are frequently used in the synthesis of various organic compounds. Indole based compounds are very important among heterocyclic structures due to their biological and pharmaceutical activities. The last decade, in particular, has witnessed considerable activity towards the synthesis of indole derivatives due to the possibilities for the design of polycyclic structures by the incorporation of multiple fused heterocyclic scaffolds in an attempt to achieve promising new heterocycles with chemical and biomedical relevance. In this study, we provide an overview on recent applications of indole in the multicomponent reactions for the synthesis of various heterocyclic compounds during the period of 2012 to 2017.