Ethylacetate, extraction with

A solution of 24.6 g of o-allyl-epoxypropoxybenzene dissolved in 250 ml of absolute ethanol saturated with ammonia was placed in an autoclave and heated on a steam-bath for 2 hours. The alcohol was then removed by distillation and the residue was redissolved in a mixture of methanol and ethylacetate. Hydrogen chloride gas was introduced into the solution. The hydrochloride salt was then precipitated by the addition of ether to yield 11.4 g of product. Five grams of the amine-hydrochloride thus formed were dissolved in 50 ml of methanol and 9 ml of acetone. The resulting solution was cooled to about 0°C. At this temperature 5 g of sodium borohydride were added over a period of 1 hour. Another 2.2 ml of acetone and O.B g of sodium borohydride were added and the solution was kept at room temperature for 1 hour, after which 150 ml of water were added to the solution. The solution was then extracted with three 100-ml portions of ether which were combined, dried over potassium carbonate, and evaporated. The free base was then recrystallized from petrol ether (boiling range 40°-60°C) to yield 2.7 g of material having a melting point of 57°C. 

Aliquots (0.25 mL) of plasma samples were mixed with 50 pL of the IS (Pfizer Global UK-115794, 20 /ig/mL in water) followed by 0.5 mL 0.2M ammonium acetate buffer (pH 9.0), extracted with 7 mL ethylacetate diethylether (1 1 v/v), vortexed for 90 sec, centrifuged at 1500 g for 3 min, and frozen. The organic layer was collected, evaporated to dryness at 40°C under a stream of nitrogen, reconstituted with 0.2 mL of mobile phase, and centrifuged at 10,000 g for 6 min. The supernatant was collected and assayed. The injection volume was 30 pL. Figure 11.2 shows chromatograms of voriconazole and the IS in plasma. 

Warm to dissolve 1.5 g 2,3-dihydro-LSD in 5 ml acetone, 40 ml water and 40 ml saturated NaHC03. Cool to 20° and add all at once with vigorous stirring 2.46 g potassium nitro-sodisulfonate dissolved in 90 ml water and 10 ml saturated NaHC03. After 1 minute, extract 7 times with ethylacetate, wash the combined extracts with water, dry and carefully remove solvent to get a mixture of 12-OH-LSD, LSD and starting material which can be chromatographed to give about 0.2 g 12-OH-LSD. 

Dried and powdered aerial parts of the plant (500 g) were extracted with actone at room temperature for 24 h. After filtration, the extract was evaporated in vacuo to a small volume. The extract was concentrated by distillation and evaporated to dryness. The residue (16 g) was chromatographed over a silica gel column eluting with on petroleum ether, a gradient of petroleum ether-chloroform, up to chloroform, followed by chloroform-ethylacetate, up to ethylacetate and fiially with methanol. 

Mix 230 ml of dry ethanol with 32.5 g of sodium methoxide under a nitrogen atmosphere until the methoxide is dissolved. Add 110 g of diethyl malonate and stir for 10 min, then add 75 g of 3-nonene-2-one (or equimolar amount of 5,6-dimethylundec-3-ene-2-one for dimethyl-heptyl) keeping the temp below 49° with external cooling. Stir and reflux for 3 hours, cool to room temp, neutralize with coned HCL add (about 45 ml), and let stand for 8-12 hours. Evaporate in vacuo, and dissolve the residue in 1 N HCl acid and 800 ml ethylacetate. Allow to stand to separate the ethyl acetate, then wash it (the acetate) with two 300 ml portions of water and extract with a saturated solution of NaHCOs until a small sample shows no turbidity upon acidification (it will take at least nine 100 ml portion extractions). Combine the NaHCOs extractions and very carefully acidify them with tiny portions of acid. Extract with three 300 ml portions of ether, and remove the ether by evaporation in vacuo after drying with MgS04 to get the methyl-carboxylate. 

Extraction with a mixture of CH2C12, ethylacetate, MeOH, and NH4OH. Decantation, filtration, evaporation to dryness. Ether-MeOH dissolution, HC1 extraction. Acid layers washed with hexane, basified, LLE in CH2C12. Organic extract evaporated, dissolved in MeOH, and filtered. 

A mixture of amide (1 mmol), aldehyde (1 mmol and in the case of 2a, 1.5 mmol as 40% solution in water) and amine (1.5 mmol) were mixed and ground with the solid support in a mortar. The mixture was transferred to a screw-cap Teflon container and irradiated in microwave oven for the required time. The progress of reaction was monitored with TLC. After cooling, the mixture was extracted with ethylacetate and filtered off. Evaporation of the solvent and remaining amine under reduced pressure gives the crude product that if necessary can be purified by recrystallization or chromatography. 

Cyclization of aminodimethylchromenylbenzophenone 6-(2-aminobenzoyl)-5,7-dimethoxy-2,2-dimethylchromene (0.12 g) was dissolved in DMSO (8 ml) and NaH (0.06 g) added, the mixture was stirred for 6 days at room temperature. A further addition of NaH (0.06 g) was made and the solution heated to 50°C for 0.5 h whence it was poured into water, extracted with EtOAc and worked up in the usual way to give a crude mixture (0.11 g components). Separation of this mixture on plate (silica gel benzene EtOAc, 10 4) gave band 1 (Rf 0.45 38 mg) identified as starting material. Band 2 (Rf 0.32 42 mg 43%) which crystallized from ethylacetate as des-N-methylisoacronycine, MP 293°-295°C. Band 3 (Rf 0.10 29 mg, 29%) crystallized from ethyl acetate as des-N-methylacronycine. MP 237°-240°C. 

A mixture of 59.5 g (0.2 mol) 2-(4-methoxybenzyl)-l,3,3-trimethyl-4-piperidone hydrochloride and 53.8 g (0.4 mol) of aluminum trichloride and 54.0 g of nitrobenzene in 1500 ml of dry benzene are boiled under reflux for 1 h. After cooling the reaction mixture is extracted with 750 ml 4 N sodium hydroxide solution, the temperature being maintained below 35°C. The organic phase is separated and extracted with 750 ml 1 N hydrochloric acid. The acid aequeous phase is rendered alkali by the addition of 100 ml 25% ammonia and extracted three times with 250 ml chloroform. The collected chloroformic phases are dried with sodium sulfate and evaporated under reduced pressure. The residue, 46.7 g, is converted into the hydrochloride by reaction with iso-propanol/HCI and crystallized from a mixture of methanol and ethylacetate. 44.6 g of the 5-hydroxy-2 -methoxy-2,9,9-trimethyl-6,7-benzomorphan hydrochloride are obtained, melting point 233-236° C (dec.). 

To a suspension of 7-amino-3-vinyl-3-cephem-4-carboxylic acid (11.25 g), 2-(aminothiazol-4-yl)-2-(tert-butoxycarbonylmethoxyimino)acetic acid S-mercaptobenzothiazole ester (23.88 g) in ethylacetate (266 ml) and water (9 ml) at 2°C is added triethylamine. After completion of the reaction, water is added and pH is adjusted to 2.1 with diluted sulfuric acid. The phases are separated and the aqueous phase is extracted with ethylacetate. The organic extracts are combined and concentrated to a volume of 120 ml, then acetonitrile (100 ml) and formic acid (22 ml) are added. The mixture is stirred at 30-35°C for 1 hour. The mixture is cooled to 2°C, the precipitate is filtered, washed with acetonitrile and dried to obtain 20.86 g of 5-thia-l-azabicyclo(4.2.0)oct-2-ene-2-carboxylic acid, 7-(((2Z)-(2-amino-4-thiazolyl)(carboxymethoxy)imino)acetylamino)-3-ethenyl-8-oxo-, (6R,7R)-(Cefixime). 

A solution of 19.9 g of morpholine, 14.8 g of diisopropylethylamine and 28.7 g of 3,4-difluoronitrobenzene in 100 mL of ethylacetate was refluxed under nitrogen for 4 hours. The mixture was allowed to cool to room temperature overnight, then 100 mL of ethyl acetate, 150 mL of methylene chloride, and 150 mL of water were added, and the aqueous layer extracted with methylene chloride and ethyl acetate. The combined organic layers were dried (Na2S04) to give a yellow solid. This was recrystallized from acetone-water to give 3-fluoro-4-morpholinyl-nitrobenzene as a yellow solid, m.p. = 112-113°C. 

In this process, 1.2 g of ll-(3-dimethylaminopropyl)-ll-hydroxy-2-(2-triphenylmethyloxyethyl)-6,ll-dihydrodibenz[b,e]oxepin is dissolved in 50 ml of pyridine. To the solution is dropwise added 0.8 g of phosphorusoxychloride under a nitrogen atmosphere and ice-cooling. After stirring the mixture at room temperature for one hour, the solvent is distilled away under reduced pressure. The residue is extracted with 100 ml of methylene chloride, and washed with saturated aqueous sodium bicarbonate solution and saturated aqueous sodium chloride solution in order. After drying the mixture over anhydrous sodium sulfate, the solvent is distilled away under reduced pressure. The resultant residue is purified by column chromatography on silica gel (eluent hexane ethylacetate triethylamine = 10 10 1) to obtain 0.82 g of the desired product as a colorless oily matter. 

HCPT (0.364 g 0.01 mmol) and 40% aqueous dimethylamine (12 ml) was added in dichloromethane (50 ml) in which anhydrous potassium carbonate (2.17 g, 15 mmol) has been suspended. The reaction mixture was stirred at room temperature for 5 h, then filtered and solid extracted with ethylacetate (20 ml). The solvent is evaporated in vacuo giving a residue. The residue was triturated with 0.5% aq HCI (50 ml) to dissolve the water-soluble adduct. Water-soluble were partitioned with petroleum ether (3 times 50 ml) and followed by ethylacetate (3 times 50 ml). The aqueous layer was lyophilized as an off white hydrochloride salt of 9-[(dimethylamino)methyl]10-hydroxy(20S)-camptothecin (topotecan hydrochloride) yield 0.236 g (65%). 

A solution of N-(4-nitrophenylacetyl)-l,2,3,4-tetrahydro-6,7-dimethoxy-l-methylisoquinoline (38.3 g, 0.1035 m) in a mixture of methanol (500 ml), ethylacetate (500 ml) and cone. HCI (8 ml) in a pressure bottle was treated with 5.0 g 5% Pd/C catalyst under nitrogen and the mixture hydrogenated on a Parr apparatus at 50 psi for 4 hr. The catalyst was removed by filtration and the solvent evaporated to a solid residue. The solid was dissolved in water (2 liters), filtered, then basified to pH with 50% NaOH. Extraction with CHCI3 (3 x 250 ml) and evaporation of the extracts gave N-(4-aminophenylacetyl)-l,2,3,4-tetrahydro-6,7-dimethoxy-l-methylisoquinoline as an off-white solid, 30.4 g (85% yield). 

Wilfordil Hook F (celastraceae) on the basis of bioassay-directed fractionation. The ethanol extract was concentrated in an ethylacetate layer of an ethylacetate-water participation. The ethylacetate extract was eluted on silica gel with chloroform and 5% methanol in chloroform. The latter fraction was further chromatographed on silica AR-CC-7 with chloroform to yield a triptolide-enriched fraction. This was further chromatographed on silica AR CC-7 to yield triptolide (137) which on crystallization from CH2Cl2-Et20 was obtained as white needles, m.p. 

Dry clean tanshen rhizomes were powdered and extracted with hexane for three days at room temperature. The hexane solution was kept overnight and then filtered. After removal of the solvent a residue was obtained which was separated into seven colored fractions by column chromatography with silica gel. Miltirone was isolated by preparative tic from fraction 1 (light red) using hexane ethyl acetate (4 1) followed by benzene-acetone (20 1). The product obtained was recrystallized from ethylacetate, m.p. 100-101°C. Its structure was confirmed by mass spectrum, NMR, IR and UV spectra which agree quite closely with those of Ho et al [76], Miltirone showed antioxidant behavior comparable to that of the commonly used phenolics BHT and BEA [77], The antioxidant activity of miltirone in lard at 100°C was determined with a Rancimat. Miltirone and other related compounds may have the potential of being used as natural antioxidants in food and cosmetics. 

Nimodipine was determined using a HPTLC method in tablets after their extraction with methanol (paracetamol was used as an internal standard). The plates were developed with toluene/ethylacetate (1 1), and densito-metric detection was effected at 240 nm. Calibration graphs were linear from 25 ng (the detection limit) to 200 ng. Recovery was 96.03%, and the relative standard deviation was 0.56% [13]. 

Therefore the condensed product is treated by adsorption on charcoal followed by desorption with acetone. The acetone solution is distilled, and the chiral units are finally obtained. In some cases, such as C4 chirals, extraction with a solvent such as ethylacetate, butylacetate or butanol can be used. The method chosen depends on the solubility of the chiral compound in water or the solvent. 

The third column (118) was a simple rectification column in which decane was separated from THF/ ethylacetate. Decane was recycled into the extraction column 116. Compared to different alternatives, which were simulated, this process has the following advantages. Water was eliminated from the ethylacetate/ THF-mixtures before their rectification. This approach takes advantage of the fact that the VLE-data of ethylacetate/ THF are more favorable than the ones of ethylacetate/ THF/ water. The counter current extraction with decane allows an efficient separation of the polar impurities such as methanol, ethanol, and acetic acid. Furthermore decane eliminated the water from the recovered solvent mixture (extractive rectification in column 117). Methylacetate posed a further problem and a rectification column was necessary to separate it from THF. The stripping column 117 combined the dewatering and the elimination of methylacetate. 

The reduced amino compound was extracted with ethylacetate after initial filtration, dried over anhydrous Na2S04 over night, filtered and evaporated the solvent. The product was recrystallised from methanol and identified by their melting points and IR spectra. 

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