An efficient and mild methodology for rapid and efficient synthesis of isatin Schiff bases was described under microwave irradiation and solvent free condition.aromatic or heterocyclic Primary amines and isatin could be selectively reacted under microwave irradiation into the corresponding isatin Schiff bases in high yields and short reaction time.  

The chemical composition of the essential oils was influenced by many factors including extraction methods. In this study, the effect of extraction methods; hydrodistillation, microwave assisted hydrodistillation and solvent free microwave extraction of Mentha piperita L. growing in Taif, KSA, on the yield and chemical composition of their essential oils were investigated. Furthermore, the oils...

Microwave-assisted extraction (MAE) and microwave-assisted hydrolysis (MAAH) were developed for the sample preparation of guava leaves prior to GC determination of quercetin and its glycosides. Ethanol was selected as the solvent. The optimum MAE temperature, particle size, solvent volume and MAE time are 120 degrees C, 40 - 60 mesh, 20 mL and 5 min, respectively; the optimum MAAH temperature a...

A calcium sennoside was extracted by developed microwave assisted extraction technique from Senna leaves. Microwave extraction was carried out at 250 W for 20 minutes, 350 W for 15 minutes and 450 W for 10 min heating period, these produced increase yields of calcium sennosides when compared to conventional heating. The yield of calcium sennosides obtained by microwave extraction was found to b...

An alternative method for the extraction of polychlorinated biphenyls (PCBs) in ash samples, which is less time and solvent consuming than Soxhlet extraction, is presented. A study was carried out to evaluate the possibilities of microwave-assisted extraction (MAE) to determine exactly which parameters affect the efficiency of the process, since direct extrapolation of extraction conditions for...

A modeling technique based on absorbed microwave energy was proposed to model microwave-assisted extraction (MAE) of antioxidant compounds from cocoa (Theobroma cacao L.) leaves. By adapting suitable extraction model at the basis of microwave energy absorbed during extraction, the model can be developed to predict extraction profile of MAE at various microwave irradiation power (100-600 W) and ...

Plant extracts having an antiplatelet aggregation activity may be a potential choice for development of antiinflammatory drugs because of their natural origin. The extraction of bioactive compounds being the most crucial step in the commercial development of natural products it is essential to have rapid and efficient phytochemical extraction methods. Extracts of B. monnieri were prepared using...

In the last 10 years there has been an increased interest in using techniques involving microwave-assisted extraction and pressurised solvent extraction in analytical laboratories. This review gives a brief overview of both methods, and reports on their application to the extraction of natural products. The influence of parameters such as the nature of the solvent and volume, temperature, time ...

a phosgene-free synthesis of symmetrical n,n'-disubstituted urea by the reaction of aromatic and aliphatic primary amines and urea promoted by  microwave irradiation in the presence of a suitable energy-transfer solvent such as n-n-dimethylacetamide is described.