the seasonal variation of volatile oil compositions (vocs) from fresh flowers of persian musk rose was investigated by combi pal headspace techniques. in this study, a total number of 21 vocs were detected by headspace on the combi pal system and gas chromatography-mass spectrometry (hs-gc/ms) from rosa moschata herrm. at different seasons which was representing 92.53-99.37% of total vocs. the ...

the synthesis of functionalized 2-oxo-2h-coumarin derivatives has been studied by a one-pot reaction of o-hydroxybenzaldehyde, ethyl 2-bromoacetate and triphenylphosphine in the presence of catalytic amount of triethyl amine in etoac, water or under solvent free conditions. we have found the best results obtained under solvent free condition.

in the chemical industry, process intensification is needed to meet important goals such as sustainable and eco-friendly processes. for esterification reaction the “produce more with less pollution” objective can be achieved by coupling reaction and separation in a so called integrated process. in this work a model for describing the esterification reaction of ethyl acetate in pervaporation mem...

losartan potassium is a well known orally active non-peptide angiotensin ii receptor antagonist. losartan potassium and its principle active metabolites block the vasoconstrictor and aldosterone secreting effect of angiotensin ii by selectively blocking the binding of angiotensin ii to at1 receptors. the drug is reported to promote the decrease in ventricular hypertrophy, salt and water excreti...

We investigated the effect of different solvents (ethyl acetate, methanol, acetone, and chloroform) on the extraction of phytoconstituents from Lantana camara leaves and their antioxidant and antibacterial activities. Further, GC-MS analysis was carried out to identify the bioactive chemical constituents occurring in the active extract. The results revealed the presence of various phytocompound...

natural substances extracted from plants have recently been considered as potential sunscreen resources because of their ultraviolet ray absorption in the uva region and their antioxidant activity. in the present study, the uv protective effects of ethyl acetate extracts of some common medicinal plants, which have flavonoids and other phenolics as the most important components, were evaluated u...

the cycloalkylation of diethyl malonate and ethyl cyanoacetate with alkyl dihalide was investigated by using comminuted potassium carbonate as a base and toluene as a solvent in the presence of hexadecyltrimethylammonium bromide (htmab) as a phase-transfer catalyst, which provided a conventional procedure with the advantage of short reaction period and high product yield. the factors influencin...

normal 0 false false false en-us x-none ar-sa backgrounds : lumbar disc herniation (ldh) is the most common surgical intervention of spine surgery. during few days of the operation, most patients experience worrying low back pain ( lbp) and radicular leg pain (rlp). applying liquid form of bupivacaine in the vicinity of surgical field could be effective on pain relief only for few hours after o...

mercaptans are commonly present in petroleum products. their foul odor and highly corrosive nature make them the most undesirable sulfur compounds so they should be removed because of environmental issues. merox process is used for oxidation of mercaptans to disulfide using air in the presence of alkaline solution and merox catalyst. in this paper, due to lack of information about the kinetic o...