Assay— Dissolve about 170mg,accurately weighed,in 40mLof water.Titrate with 0.1Nsodium hydroxide VSdetermining the endpoint potentiometrically.Perform a blank determination and make any necessary correction.Each mLof 0.1Nsodium hydroxide is equivalent to 33.95mg of C16H37NO4S.Not less than 97.0%is found.

Melting range á741ñ: between 169and 173.

Assay— Dissolve 200mg,accurately weighed,in 40mLof boiling water,with vigorous stirring,and cool to room temperature.Stir the solution by mechanical means,add 5mLof 2Nnitric acid,and titrate with 0.1Nsilver nitrate VS,determining the endpoint potentiometrically,using a glass-silver electrode system and adding the titrant in 0.1-mLincrements as the end-point is approached.Perform a complete blank determination,and make any necessary correction.Each mLof 0.1Nsilver nitrate is equivalent to 36.94mg of (C4H9)4NI:not less than 99.0%is found.

Melting range á741ñ: between 146and 147.

Assay— Dissolve about 1.5g,accurately weighed,in 100mLof water.Without delay,titrate with 0.5Nsodium hydroxide VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction.Each mLof 0.5Nsodium hydroxide is equivalent to 169.7mg of (C4H9)4NH2PO4.Not less than 97.0%is found.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with an electron-capture detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 300;the detector temperature is maintained at 300;and the column temperature is maintained at 70and programmed to rise 15per minute to 300.The area of the 13C12H4Cl4O2peak is not less than 99.0%of the total peak area.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with an electron-capture detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.32-mm ×60-m capillary column coated with a 1-µm layer of phase G27;the injection port temperature is maintained at 300;the detector temperature is maintained at 350;and the column temperature is maintained at 70and programmed to rise 15per minute to 275.The area of the C12H4Cl4Opeak is not less than 99.0%of the total peak area.

Melting range á741ñ: between 51and 53.

Assay— When examined by gas-liquid chromatography,it shows a purity of not less than 98%.The following conditions have been found suitable for assaying the reagent:a 3-mm ×2.4-m stainless steel column packed with phase G16on support S1.The carrier gas is helium,flowing at 27.5mLper minute,the column temperature is 250,the injection port temperature is 200,and the detector temperature is 280.Aflame-ionization detector is employed.

Melting range,Class IIá741ñ: between 4and 8,within a 2range.

Refractive index á831ñ: between 1.4280and 1.4300at 20.

Assay— When examined by gas-liquid chromatography,using suitable gas chromatographic apparatus and conditions,it shows a purity of not less than 90%.

Boiling range(Reagent test): between 177and 187,at a pressure of 9mm of Hg.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 250;the detector temperature is maintained at 300;and the column temperature is maintained at 150and programmed to rise 10per minute to 280.The area of the C8H23N5peak is not less than 30%of the total peak area.

Refractive index á831ñ: between 1.503and 1.507at 20.

Melting range á741ñ: between 89and 91.

Assay— Inject an appropriate sample dissolved in acetone into a gas chromatograph (see Chromatography á621ñ)that is equipped with a flame-ionization detector and contains a 0.53-mm ×30-m capillary column coated with a layer of G25.The carrier gas is helium,flowing at a rate of 9mLper minute.The chromatograph is programmed as follows.Initially the column temperature is equilibrated at 150,then the temperature is increased at a rate of 10per minute to 250.The injection port temperature is maintained at 240,and the detector temperature at 265.The area of the tetrahydro-2-furancarboxylic acid peak is not less than 97%of the total peak area.

Refractive index á831ñ: 1.4600.

Boiling range: between 128and 129at a pressure of 13mm of Hg.

Density: 1.209.

Peroxide— Transfer 8mLof potassium iodide and starch TSto a 12-mLground glass-stoppered cylinder about 15mm in diameter.Fill completely with the substance under test,mix,and allow to stand protected from light for 5minutes.No color develops.

Refractive index á831ñ: 1.5401at 20.

Assay— Transfer about 200mg,accurately weighed,to a beaker,add 50mLof water and 10mLof diluted nitric acid,swirl to dissolve the test specimen,add 50.0mLof 0.1Nsilver nitrate VS,and mix.Add 2mLof ferric ammonium sulfate TSand 5mLof nitrobenzene,shake,and titrate the excess silver nitrate with 0.1Nammonium thiocyanate VS:each mLof 0.1Nsilver nitrate is equivalent to 10.96mg of (CH3)4NCl.Not less than 98%is found.

Assay— Accurately weigh a glass-stoppered flask containing about 15mLof water.Add a quantity of a solution of tetramethylammonium hydroxide,equivalent to about 200mg of (CH3)4NOH,and again weigh.Add methyl red TS,and titrate the solution with 0.1Nhydrochloric acid VS:each mLof 0.1Nacid is equivalent to 9.115mg of (CH3)4NOH.

Residue on evaporation— Evaporate 5mLof solution on a steam bath,and dry at 105for 1hour:the weight of the residue is equivalent to not more than 0.02%of the weight of the test specimen.

Ammonia and other amines— Accurately weigh a quantity of solution,corresponding to about 300mg of (CH3)4NOH,in a low-form weighing bottle tared with 5mLof water.Add a slight excess of 1Nhydrochloric acid (about 4mL),evaporate on a steam bath to dryness,and dry at 105for 2hours:the weight of the tetramethylammonium chloride so obtained,multiplied by 0.8317,represents the quantity,in mg,of (CH3)4NOHin the portion of test specimen taken and corresponds to within 0.2%above or below that found in the Assay.

Assay— Accurately weigh about 800mg,dissolve in 100mLof water,and titrate with 0.1Nhydrochloric acid VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nhydrochloric acid is equivalent to 18.22mg of (CH3)4NOH·5H2O:not less than 98%is found.

Assay— Accurately weigh about 1g of the solution,and dilute with water to about 50mL.Add phenolphthalein TS,and titrate with 0.1Nhydrochloric acid VSto the disappearance of the pink color:each mLof 0.1Nhydrochloric acid VSis equivalent to 91.15mg of (CH3)4NOH.Between 23%and 25%is found.

Clarity— Aportion of it in a test tube is clear,or only slightly turbid,when viewed transversely.

Melting range á741ñ: between 87and 90.

Loss on drying á731ñ— Dry it at 105for 4hours:it loses not more than 8%of its weight.

Assay— Dissolve about 500mg,accurately weighed,in a mixture of 80mLof water and 0.5mLof sulfuric acid.When dissolution is complete,add 20mLof hydrochloric acid.Heat to 60and maintain this temperature while titrating with 0.1Nceric sulfate VS,determining the endpoint potentiometrically,using silver-silver chloride and platinum electrodes.Each mLof 0.1Nceric sulfate is equivalent to 11.99mg of TlCl.Not less than 99%is found.

Assay— Dissolve about 34mg,accurately weighed,in 50mLof glacial acetic acid.Titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 18.02mg of C7H8N4O2.Not less than 95%is found.

Solubility— A200-mg portion mixed with 50mLof water shows not more than a faint haze.

Residue on ignition— Accurately weigh about 1.5g,previously dried at 105for 2hours,and ignite until thoroughly charred.Cool,add 2mLof nitric acid and 2mLof sulfuric acid,ignite gently to expel excess acids,then at 600to 800to constant weight:the residue of sodium sulfate (Na2SO4)is between 19.8%and 21.5%of the weight of the test specimen (theory is 20.4%).

Sensitiveness to magnesium— Add 0.2mLof a solution (1in 10,000)and 2mLof 1Nsodium hydroxide to a mixture of 9.5mLof water and 0.5mLof a solution prepared by dissolving 1.014g of clear crystals of magnesium sulfate in water,diluting with water to 100mL,then diluting 10mLof the resulting solution with water to 1liter:a distinct pink color is produced within 10minutes.

Melting temperature á741ñ: 236,with decomposition.

Assay— Not less than 98%of C4H10O2Sis found,a suitable gas chromatograph equipped with a flame-ionization detector being used.The following conditions have been found suitable:a 4.0-mm ×1.83-m glass column is packed with 10%phase G25on support S1A;the column,injection port,and detector temperatures are maintained at 200,250,and 310,respectively.

Refractive index á831ñ: between 1.4250and 1.4270,at 20.

Residue on ignition(Reagent test): not more than 0.1%.

Solubility— Asolution of 1mLin 10mLof water is clear and colorless.

Sensitiveness— Mix 1mLwith 2mLof stronger ammonia water,and dilute with water to 20mL.Add 1mLof this solution to a mixture of 20mLof water and 0.1mLof dilute ferric chloride TS(1in 100),then add 5mLof ammonia TS:a distinct pink color is produced.

Loss on drying á731ñ— [NOTE—This test is applicable only to the dry form.]Dry it in vacuum at 60for 6hours:it loses not more than 5.0%of its weight.

Melting range á741ñ: between 48and 51,but when melted it remains liquid at a considerably lower temperature.

Nonvolatile matter— Volatilize 2g on a steam bath,and dry at 105to constant weight:the residue weighs not more than 1mg (0.05%).

Add the following:

Assay— Accurately weigh 0.75g into 100mLof 2Nsulfuric acid contained in a Smith weighing buret.Pour the solution through a zinc-mercury reduction column into 50mLof 0.1Nferric ammonium sulfate VS.Elute with 100mLof 2Nsulfuric acid and 100mLof water.Add 10mLof phosphoric acid,and titrate with 0.1Npotassium permanganate VS.Perform a blank determination,and make any necessary correction.Each mLof 0.1Npotassium permanganate is equivalent to 18.97mg of TiCl4.Not less than 99.5%is found.

Boiling range(Reagent test): between 135and 140.

Melting range á741ñ: between 129and 131.

Assay— When examined by gas-liquid chromatography,it shows a purity of not less than 98%.The following conditions have been found suitable for assaying the article:A3-mm ×1.8-m stainless steel column packed with a 5%phase G4on support S1.Nitrogen,having a flow rate of about 12mLper minute,is the carrier gas,the detector and column temperature are about 125,and the injection port temperature is about 205.Aflame-ionization detector is employed and the specimen is a 5%solution in carbon disulfide.

Refractive index á831ñ: between 1.544and 1.546,at 20.

Assay— Transfer about 650mg,accurately weighed,to a suitable container,dissolve in 125mLof alcohol,add 25mLof water,and mix.Titrate with 0.5Nsodium hydroxide VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction.Each mLof 0.5Nsodium hydroxide is equivalent to 68.07mg of C8H8O2:not less than 98%is found.

Melting range á741ñ: over a range of 2that includes 181.

Specific gravity á841ñ: 1.008at 20.

Boiling range(Reagent test): between 200and 202.

Assay— Dissolve 400mg,accurately weighed,in 100mLof glacial acetic acid,and titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 10.72mg of CH3C6H4NH2.Not less than 98%,calculated on the dried basis,is found.

Loss on drying— Weigh accurately about 1g,and dry at 30to constant weight:it loses not more than 2%of its weight.

Assay— Dissolve about 34mg,accurately weighed,in 50mLof glacial acetic acid.Titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary corrections.Each mLof 0.1Nperchloric acid is equivalent to 15.41mg of C4H6N6O.Not less than 97%is found.

Refractive index á831ñ: between 1.4205and 1.4225.

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,nitrogen being used as the carrier gas.The following conditions have been found suitable:a 3-mm ×1.8-m stainless steel column containing phase G4on support S1A;the injection port temperature is maintained at 270;the detector temperature is maintained at 300.The area of the tributyrin peak is not less than 98%of the total peak area.

Refractive index á831ñ: between 1.4345and 1.4365at 20.

Acid content— Transfer 1.0g,accurately weighed,to a beaker,add 75mLof methanol,and dissolve by stirring.When dissolution is complete,add 25mLof water,and titrate with 0.05Npotassium hydroxide VS,using phenolphthalein TSas indicator.Perform a blank determination,and make any necessary correction.Each mLof 0.05Npotassium hydroxide is equivalent to 88.1mg of butyric acid:not more than 0.5%is found.

Assay—

Melting range á741ñ: between 152and 156.

Assay— Inject an appropriate specimen into a gas chromatograph (see Chromatography á621ñ)equipped with a thermal conductivity detector,helium being used as the carrier gas.The following conditions have been found suitable:a 2.0-mm ×1.8-m glass column packed with 10%G1phase on support S1A;the injection port temperature is maintained at 50;the detector temperature is maintained at 300;and the column temperature is maintained at 0and programmed to rise 3per minute to 50.The area of the CCl3Fpeak is not less than 99%of the total peak area.

Refractive index á831ñ: between 1.380and 1.384at 20.

Melting range á741ñ: between 47and 49.

Suitability— Determine its suitability for use in the test for Related compoundsunder Propoxyphene Hydrochloride(USPmonograph)as follows.Dissolve a suitable quantity in chloroform to yield a solution containing 20µg per mL.Following the directions given in the test for Related compoundsunder Propoxyphene Hydrochloride,inject a suitable volume of the solution into the chromatograph,and record the chromatogram.Concomitantly record the chromatogram from the Standard preparationprepared as directed in the test for Related compounds:only one main peak is obtained from the n-tricosane solution,and no minor peaks are observed at,or near,the peak positions obtained for propoxyphene,acetoxy,or carbinol in the chromatogram from the Standard preparation.

Boiling range(Reagent test): between 89and 90.

Absorbance— To 1mLin a 50-mLvolumetric flask add 10mLof methanol and 1mLof hydrochloric acid,and add chloroform to volume.The absorbance of this solution,determined at the wavelength of maximum absorbance at about 285nm,with a suitable spectrophotometer,does not exceed 0.01.[NOTE—If the absorbance exceeds 0.01,purify the triethylamine as follows.Reflux 100mLwith 20mLof water and 2g of sodium hydrosulfite for not less than 8hours,wash with water,dry by refluxing,using a Dean-Stark trap,and distil,collecting only the first 75mLof the filtrate.Store over anhydrous sodium carbonate or anhydrous potassium carbonate.]

Assay— Transfer about 35mg,accurately weighed,to a suitable beaker,add 50mLof glacial acetic acid,and dissolve by stirring.Add 5mLof mercuric acetate TS,with stirring.When solution is complete,titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically.Perform a blank titration,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 13.77mg of C6H15N·HCl.Not less than 97.5%of C6H15N·HCl is found.

Melting point á741ñ: between 256and 259,with decomposition.

Assay— Inject an appropriate test specimen into a suitable gas chromatograph equipped with a flame-ionization detector (see Chromatography á621ñ),helium being used as the carrier gas.The following conditions have been found suitable:a 3-mm ×1.85-m stainless steel column packed with support S2;the injection port,column,and detector temperatures are maintained at 250,230,and 310,respectively.The area of the C6H14O4peak is not less than 97%of the total peak area.

Refractive index á831ñ: between 1.4550and 1.4570,at 20.

Assay— Dissolve about 300mg,accurately weighed,in 25mLof water and 25mLof alcohol.Titrate with 0.1Nsodium hydroxide VS,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary corrections.Each mLof 0.1Nsodium hydroxide is equivalent to 11.40mg of C2HF3O2.Not less than 99%is found.

Assay— Transfer about 0.8g,accurately weighed,to a glass-stoppered flask containing 50mLof methanol.Add 500mg of phenolphthalein,and titrate with 0.1Nsodium methoxide VSto a pink endpoint.Calculate Aby the formula: in which Vis the volume,in mL,of 0.1Nsodium methoxide and Wis the weight,in mg,of test specimen.To a second glass-stoppered flask containing 50mLof a mixture of dimethylformamide and water (1:1)transfer 0.4g,accurately weighed,of the specimen under test,add 500mg of phenolphthalein,and titrate with 0.1Nsodium hydroxide VSto a pink endpoint.Calculate Bby the formula: in which V1is the volume,in mL,of 0.1Nsodium hydroxide and W1is the weight,in mg,of test specimen.Calculate the percentage of (F3CCO)2Oby the formula: Not less than 97%is found.If 2Ais greater than B,calculate the percentage of F3CCOOHby the formula:

Assay— Inject an appropriate specimen into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 100;the detector temperature is maintained at 150;and the column temperature is maintained at 0and programmed to rise 10per minute to 150.The area of the CF3CH2OHpeak is not less than 99%of the total peak area.

Boiling range: between 77and 80.

Boiling range: between 28and 30.

Assay— When tested by thin-layer chromatography,with the use of plates coated with chromatographic silica gel mixture,a developing system consisting of chloroform,methanol,and acetic acid (17:2:1),and examined visually and under long-wavelength UVlight,a single spot is exhibited.

Melting range á741ñ: between 48and 52.

Melting range á741ñ: between 185and 192,determined after recrystallization from hot alcohol,if necessary.

Residue on ignition(Reagent test)— Ignite 1g with 0.5mLof sulfuric acid:the residue weighs not more than 10mg (1%).

Assay— Inject an appropriate test specimen into a suitable gas chromatograph (see Chromatography á621ñ),helium being used as a carrier gas.The following conditions have been found suitable:A3-mm ×1.85-m stainless steel column containing phase G16on support S1A;the injection port,column,and detector temperatures are maintained at 180,165,and 270,respectively,and a flame-ionization detector is used.The area of the C8H11Npeak is not less than 98%of the total peak area.

Refractive index á831ñ: between 1.4970and 1.4990,at 20.

Refractive index á831ñ: between 1.4744and 1.4764at 20.

Melting range á741ñ: between 54and 56.

Melting range á741ñ: between 172and 175.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 300;the detector temperature is maintained at 300;and the column temperature is maintained at 200and programmed to rise 10per minute to 300.The area of the C19H16peak is not less than 99%of the total peak area.

Melting range á791ñ: between 92and 94.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 280;the detector temperature is maintained at 300;and the column temperature is maintained at 180.The area of the C19H16Opeak is not less than 96.5%of the total peak area.

Solubility— Separate 100-mg portions dissolve completely in 10mLof water and in 10mLof alcohol,respectively,to yield solutions that are clear,or practically so.

Loss on drying á731ñ— Dry it at 105to constant weight:it loses not more than 5.0%of its weight.

Residue on ignition(Reagent test): negligible,from 100mg.

Sensitiveness— Dissolve 10mg in 10mLof dehydrated alcohol (A).Then dissolve 10mg of dextrose in 20mLof dehydrated alcohol (B).To 0.2mLof Badd 1mLof dehydrated alcohol and 0.5mLof dilute tetramethylammonium hydroxide TS(1volume diluted with 9volumes of dehydrated alcohol),then add 0.2mLof A:a pronounced red color develops within about 10minutes.

Assay— Dissolve about 80mg in 30mLof methanol.Add 40mLof water and titrate with 1Nhydrochloric acid,determining the endpoint potentiometrically.Perform a blank determination and make any necessary correction.Each mLof 1Nhydrochloric acid is equivalent to 48.75mg of C6H18N4.Not less than 98.0%is found.

Refractive index á831ñ: between 1.4956and 1.4986at 20.

Add the following:

pHrange: from 1.4(red)to 2.6(yellow).

Add the following:

Assay— Accurately weigh about 300mg,dissolve in a mixture of 3mLof formic acid and 50mLof glacial acetic acid,add 2drops of crystal violet TS,and titrate with 0.1Nperchloric acid VSto a green endpoint.Each mLof 0.1Nperchloric acid is equivalent to 20.42mg of C11H12N2O2.Between 98.0%and 102.0%,calculated on the dried basis,is found.

Specific rotation á781ñ: between -30.0and -33.0,determined in a solution containing 1.0g of test specimen,previously dried at 105for 3hours,in 100mL.

Loss on drying á731ñ— Dry it at 105for 3hours:it loses not more than 0.3%of its weight.

Residue on ignition(Reagent test): not more than 0.1%.

Tyrosine— Dissolve 100mg in 3mLof diluted sulfuric acid,add 10mLof mercuric sulfate TS,and heat on a steam bath for 10minutes.Filter,wash with 5mLof mercuric sulfate TS,and add to the combined filtrate 0.5mLof sodium nitrite solution (1in 20):no red color is produced within 15minutes.

Add the following: