Assay— When examined by gas-liquid chromatography, using suitable gas chromatographic apparatus and conditions, it shows a purity of not less than 99%.

Assay— Transfer about 1 g, accurately weighed, to a suitable, tared crucible, moisten with a few drops of sulfuric acid, and ignite gently to constant weight. Each mg of residue is equivalent to 3.662 mg of C10H21NaO4S. Not less than 95% is found.

Insoluble matter— Boil 1 g with 30 mL of water in a small flask: the solution is colorless and clear, or not more than opalescent.

Loss on drying 731— Dry it at 105 to constant weight: it loses not more than 10.0% of its weight.

Residue on ignition (Reagent test)— Ignite 1 g with 0.5 mL of sulfuric acid: the residue weighs not more than 5 mg (0.5%).

Chloride (Reagent test)— Dissolve 3 g in 75 mL of boiling water, cool, dilute with water to 75 mL, and filter if necessary. To 25 mL of the filtrate add 2 mL of nitric acid and 1 mL of silver nitrate TS, and allow to stand for 5 minutes: any turbidity produced is not greater than that of a control containing 0.02 mg of added Cl (0.002%).

Sulfate (Reagent test, Method I)— To a 25-mL portion of the filtrate from the preceding test add 0.5 mL of diluted hydrochloric acid and 2 mL of barium chloride TS, and allow to stand for 10 minutes: any turbidity produced is not greater than that of a control containing 0.2 mg of added SO4 (0.02%).

Alcohol-soluble substances— Boil 1 g with 20 mL of alcohol for 5 minutes under a reflux condenser, and filter while hot. Evaporate 10 mL of the filtrate on a steam bath, and dry at 105: the residue weighs not more than 5 mg (1%).

Reducing sugars— Shake 2 g with 100 mL of water for 10 minutes, and filter until clear. To 50 mL of the filtrate add 50 mL of alkaline cupric tartrate TS, and boil for 3 minutes. Filter through a tared filtering crucible, wash with water, then with alcohol, and finally with ether, and dry at 105 for 2 hours: the precipitate of cuprous oxide weighs not more than 115 mg (corresponding to about 5% of reducing sugars as dextrose).

Insoluble matter— Dissolve 2 g in 100 mL of water, without heating, and filter immediately: the insoluble residue does not exceed 1 mg (0.05%).

Residue on ignition (Reagent test): not more than 1 mg, from 2 g (0.05%).

Suitability test for detection of selenium— Dissolve 1.633 g of selenious acid (H2SeO3) in water, and dilute with water to 1 L. Dilute 10 mL of this solution with water to 1 liter, to make a solution containing 0.010 mg of Se per mL. Place 1 mL of the resulting solution in a 100-mL beaker, add 2 mL of formic acid solution (1 in 7), and dilute with water to 50 mL. Add 2 mL of 3,3¢-diaminobenzidine hydrochloride solution (1 in 200), and allow to stand for 30 to 50 minutes. Adjust with 6 N ammonium hydroxide to a pH between 6 and 7. Transfer to a 125-mL separator, add 10.0 mL of toluene, and shake vigorously for 30 seconds: a distinct yellow color is produced in the toluene layer. A blank containing diaminobenzidine hydrochloride but no selenium standard, treated in the same manner, shows no color in the toluene layer.

Loss on ignition— Accurately weigh about 4 g, and ignite to constant weight: it loses not more than 10.0% of its weight.

Organic impurities— It does not darken appreciably upon ignition.

Loss on drying 731— Dry it at 110 for 2 hours: it loses not more than 2.0% of its weight.

Melting range 741 : between 82 and 84.

Solubility in alcohol— A solution of 100 mg in 10 mL of alcohol is not more than faintly turbid.

Residue on ignition (Reagent test)— Ignite 500 mg with 0.5 mL of sulfuric acid: the residue weighs not more than 1 mg (0.2%).

Sensitiveness— To 10 mL of a water solution containing 0.01 mg of phenol add 0.3 mL of a sodium borate buffer (made by dissolving 2.84 g of crystallized sodium borate in 90 mL of warm water, adding 8.2 mL of 1 N sodium hydroxide and diluting with water to 100 mL) and 0.1 mL of a solution of 10 mg of the test specimen in 20 mL of alcohol: a distinct blue color develops within 10 minutes.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography 621) 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 200; the detector temperature is maintained at 300; and the column temperature is maintained at 100 and programmed to rise 10 per minute to 200. The area of the C8H19N peak is not less than 99% of the total peak area.

Refractive index 831: between 1.415 and 1.419 at 20.

Assay— Accurately weigh about 2 g into a suitable flask, add 25.0 mL of 1 N sodium hydroxide and 30 mL of isopropyl alcohol, and mix. Digest the mixture at a temperature near boiling for 30 minutes, then cool in a water bath to room temperature. Add phenolphthalein TS, and titrate with 1 N sulfuric acid VS to the disappearance of the pink color. Perform a complete blank determination, and make any necessary correction. Each mL of 1 N sulfuric acid consumed is equivalent to 139.2 mg of C16H22O4. Not less than 98% is found.

Refractive index 831: between 1.491 and 1.493 at 20.

Acid content— Accurately weigh about 10 g, and dissolve in 100 mL of an alcohol-ether mixture (1:1). Add phenolphthalein TS, and titrate immediately with 0.05 N alcoholic potassium hydroxide VS. Each mL of 0.05 N alcoholic potassium hydroxide is equivalent to 4.15 mg of phthalic acid: not more than 0.02% is found.

Melting range, Class I 741 : between 49 and 50.

Melting range 741 : between 38 and 41.

Change to read:

Assay— When examined by gas–liquid chromatography, with the use of suitable apparatus and conditions, it shows a purity of not less than 98%.

Density: between 1.299 and 1.301.

Refractive index 831: between 1.548 and 1.550 at 25.

Residue on evaporation— Evaporate 80 mL on a steam bath, and dry at 105 for 1 hour: the residue weighs not more than 50 mg (0.005%).

Acidity— Add phenolphthalein TS to 25 mL of methanol, and titrate with 0.02 N alcoholic potassium hydroxide VS until a faint pink color persists for 15 seconds. Pipet 25 mL of test specimen into the solution; mix, avoiding exposure to the atmosphere; and titrate with 0.02 N alcoholic potassium hydroxide VS: not more than 2.2 mL is required to restore the pink color (about 0.005%).

Assay—

Residue on ignition (Reagent test)— Ignite 200 mg with 5 drops of sulfuric acid: the residue weighs not more than 1 mg (0.5%).

Sensitiveness— Dissolve 100 mg in 60 mL of alcohol, add 2.5 mL of 0.1 N sodium hydroxide, and dilute with water to 100 mL. Add 1 mL of this solution to a solution of potassium iodide prepared by dissolving 100 mg of potassium iodide, previously dried at 105 to constant weight and accurately weighed, in 50 mL of water containing 1 mL of glacial acetic acid, and titrate with 0.1 N silver nitrate VS until the color of the precipitate changes from pale yellowish orange to pink. The volume of 0.1 N silver nitrate consumed is not more than 0.10 mL greater than the calculated volume, the calculated volume being based upon the KI content of the dried specimen as determined in the Assay under Potassium Iodide (USP monograph).

Assay— Inject an appropriate specimen into a gas chromatograph (see Chromatography 621) equipped with a thermal-conductivity detector, helium being used as the carrier gas. The following conditions have been found suitable: a 0.53-mm × 30-m capillary column coated with a 5-µm layer of phase G2; the injection port temperature is maintained at 200; the detector temperature is maintained at 200; and the column temperature is maintained at 0 and programmed to rise 5 per minute to 40, and then to rise at 10 per minute to 180. The area of the CHCl2F peak is not less than 98% of the total peak area.

Melting range 741 : between 103 and 107, but the range between beginning and end of melting does not exceed 2.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography 621) 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 230; the detector temperature is maintained at 300; the column temperature is maintained at 130 and programmed to rise 10 per minute to 280. The area of the C6H4Cl2O peak is not less than 98.5% of the total peak area.

Assay— Inject an appropriate specimen into a gas chromatograph (see Chromatography 621) 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 150 and programmed to rise 10 per minute to 280. The area of the C8H6Cl2O2 peak is not less than 97% of the total peak area.

Melting range 741 : between 65 and 67.

Solubility in alcohol— A solution of 100 mg in 10 mL of alcohol is complete and clear.

Residue on ignition— Ignite 500 mg with 0.5 mL of sulfuric acid: the residue weighs not more than 1 mg (0.2%).

Sensitiveness— It meets the requirements of the test for Sensitiveness under 2,6-Dibromoquinone-chlorimide.

Change to read:

Assay— Accurately weigh about 400 mg in a tared, small weighing bottle equipped with a well-fitting closure. Transfer the stoppered bottle to a 250-mL beaker, add sufficient glacial acetic acid TS to cover the bottle, and open the bottle under the surface of the acid. Add crystal violet TS, and titrate with 0.1 N perchloric acid VS. Each mL of 0.1 N perchloric acid is equivalent to 18.13 mg of (C6H11)2NH. Not less than 98% is found.

Specific gravity 841: between 0.911 and 0.917.

Boiling range (Reagent test): between 255 and 257.

Water, Method I 921: not more than 0.5%.

Melting range 741: between 62 and 66.

Assay— Inject an appropriate specimen (about 0.2 µL) into a suitable gas chromatograph (see Chromatography 621) equipped with a flame-ionization detector, helium being used as the carrier gas flowing at about 40 mL per minute. The following conditions have been found suitable: a 3-mm × 1.8-m stainless steel column containing 20% phase G16 on support S1A; the injection port temperature is maintained at 250; the column temperature is maintained at 140 and programmed to rise 6 per minute to 200. The detector temperature is maintained at 310. The area of the N,N-diethylaniline peak having a retention time of about 4.9 minutes is not less than 99% of the total peak area.

Refractive index 831: between 1.5405 and 1.5425 at 20.

Specific gravity 841: between 1.117 and 1.120 at 20.

Distilling range 721: between 240 and 250.

Acidity— Transfer 54 mL (60 g) to a 250-mL conical flask, add phenolphthalein TS, and titrate with 0.02 N alcoholic potassium hydroxide VS to the production of a pink color that is stable for at least 15 seconds: not more than 2.5 mL is consumed (0.005% as CH3COOH).

Water 921: not more than 0.2%.

Residue on ignition 281— Transfer 50 g to a tared platinum dish, heat the dish gently until the vapors ignite, and allow the specimen to burn completely. Ignite the residue at 800 ± 25, cool, and weigh: the residue weighs not more than 2.5 mg (0.005%).

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography 621) 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 G2. The injection port temperature is maintained at 200; the column temperature is maintained at 100 and programmed to rise 10 per minute to 250 and held there for 5 minutes. The detector temperature is maintained at 300. The area of the main peak is not less than 95% of the total peak area.

Refractive index 831: between 1.4815 and 1.4845 at 20.

Specific rotation 781: between 47 and 49, determined in a solution in 75 percent acetic acid containing 100 mg per mL.

Solubility in alcohol— A solution of 500 mg in 20 mL of warm alcohol is colorless and complete.

Loss on drying 731— Dry it at 105 to constant weight: it loses not more than 6% of its weight.

Residue on ignition (Reagent test): not more than 0.3%.

Assay— When tested by thin-layer chromatography, with the use of plates coated with chromatographic silica gel mixture, a developing system consisting of toluene and methanol (80:20), and examined visually and under long-wavelength UV light, a single spot is exhibited.

Assay—

Assay—

Assay— Dissolve about 75 mg, accurately weighed, in 30 mL of methanol. Slowly add 40 mL of water. Titrate with 0.1 N sodium hydroxide VS, determining the endpoint potentiometrically. Perform a blank determination and make any necessary correction. Each mL of 0.1 N sodium hydroxide is equivalent to 15.41 mg of C7H6O4. Not less than 99% is found.

Melting range 741 : about 207, with decomposition.

Change to read:

Residue on ignition— Ignite 200 mg with 5 drops of sulfuric acid: the weight of the residue does not exceed 1.0 mg (0.5%).

Sensitiveness— Accurately weigh about 100 mg of potassium iodide, previously dried at 105 to constant weight, and dissolve it in 50 mL of water. Add 1 mL of diiodofluorescein TS prepared from the test specimen and 1 mL of glacial acetic acid, and titrate with 0.1 N silver nitrate VS until the color of the precipitate changes from brownish red to a bluish red. The volume of 0.1 N silver nitrate consumed is not in excess of 0.10 mL over the calculated volume, based on the KI content of the dried potassium iodide determined as follows. Dissolve about 500 mg of potassium iodide, accurately weighed, in about 10 mL of water, and add 35 mL of hydrochloric acid and 5 mL of chloroform. Titrate with 0.05 M potassium iodate VS until the purple color of iodine disappears from the chloroform. Add the last portions of the iodate solution dropwise, agitating vigorously and continuously. After the chloroform has been decolorized, allow the mixture to stand for 5 minutes. If the chloroform develops a purple color, titrate further with the iodate solution. Each mL of 0.05 M potassium iodate is equivalent to 16.60 mg of KI.

Specific gravity: between 0.716 and 0.720.

Distilling range, Method II 721— Not less than 95% distils between 65 and 70.

Peroxides— To 10 mL, contained in a clean, glass-stoppered cylinder previously rinsed with a portion of the ether under examination, add 1 mL of freshly prepared potassium iodide solution (1 in 10). Shake, and allow to stand for 1 minute: no yellow color is observed in either layer (about 0.001% as H2O2).

Residue on evaporation— [Note—If peroxide is present, do not carry out this procedure.] Evaporate 14 mL (10 g) from a tared shallow dish, and dry at 105 for 1 hour: the residue weighs not more than 1 mg (0.01%).

Acidity— Add 2 drops of bromothymol blue TS to 10 mL of water in a glass-stoppered, 50-mL flask, and titrate with 0.010 N sodium hydroxide until a blue color persists after vigorous shaking. Add 5 mL of Diisopropyl Ether, and titrate with 0.010 N sodium hydroxide: not more than 0.30 mL is required to restore the blue color (0.005% as CH3COOH).

NOTE—For spectrophotometric determinations, use diisopropyl ether that meets the following additional requirement:

Absorbance— Its absorbance at 255 nm, in a 10-mm quartz cell, does not exceed 0.2, water being used as the blank.

Assay— Not less than 98% of C6H15N is found, a suitable gas chromatograph equipped with a flame-ionization detector being used. The following conditions have been found suitable: a 3.2-mm × 1.83-m stainless steel column is packed with a cross-linked polystyrene support; the injection port temperature is maintained at 250 and the detector at 310; the column temperature is programmed to rise at 10 per minute from 50 to 220.

Refractive index 831: between 1.3915 and 1.3935, at 20.

Assay— Accurately weigh about 500 mg, dissolve in 50 mL of glacial acetic acid, mix, add crystal violet TS, and titrate with 0.1 N perchloric acid VS. Each mL of 0.1 N perchloric acid is equivalent to 12.92 mg of C8H19N. Not less than 98% is found.

Refractive index 831: between 1.4125 and 1.4145 at 20.

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography 621) equipped with a flame-ionization detector, nitrogen being used as the carrier gas. The following conditions have been found suitable: a 0.3-mm × 30-m capillary column coated with phase G1; the injection port temperature is maintained at 270; the detector temperature is maintained at 300; the column temperature is maintained at 150 and programmed to rise 10 per minute to 270. The area of the main peak is not less than 97% of the total peak area.

Melting range 741: between 50 and 52.

Change to read:

Boiling range (Reagent test)— Not less than 95% distills between 83 and 86.

Refractive index 831: between 1.379 and 1.381, at 20.

Acidity— To 20 mL add bromophenol blue TS, and titrate with 0.020 N sodium hydroxide: not more than 2.0 mL is consumed (about 0.015% as CH3COOH).

Water, Method I921: not more than 0.2%.

Melting range 741 : between 65 and 67.

Assay—

Refractive index 831: between 1.514 and 1.518 at 20.

Melting range 741: between 109 and 111.

Assay— When examined by gas-liquid chromatography, with the use of suitable apparatus and conditions, it shows a purity of not less than 99%.

Distilling range 721: between 164.5 and 167.5.

Residue on evaporation— Evaporate 215 mL on a steam bath, and dry at 105 for 1 hour: the residue weighs not more than 2 mg (0.001%).

pH of 20% solution— Weigh 20 g of it into a 100-mL volumetric flask, and dilute with carbon dioxide-free water to volume: the solution shows a pH between 4.0 and 7.0.

Ultraviolet absorbance— Determine its absorbance throughout the range 270 to 400 nm, using a 1-cm cell, a suitable spectrophotometer, and water to set the instrument: the absorbance does not exceed 1.00 at 270 nm, 0.30 at 280 nm, 0.15 at 290 nm, 0.05 at 310 nm, 0.03 at 320 nm, and 0.01 at 360 to 400 nm.

Water, Method I 921: not more than 0.05%.

Solubility— Insoluble in water; sparingly soluble in chloroform, in ether, or in fatty oils. Dissolve 100 mg in 20 mL of alcohol: the solution is complete or practically so and clear.

Melting range 741: between 115 and 117.

Residue on ignition 281: not more than 0.1%.

Sensitiveness— Add 0.05 mL of an alcohol solution (1 in 200) and 2 g of ammonium chloride to 25 mL of carbon dioxide-free water: the lemon-yellow color of the solution is changed to orange by the addition of 0.05 mL of 0.1 N hydrochloric acid and restored on the subsequent addition of 0.05 mL of 0.1 N sodium hydroxide.

Melting range 741 : between 132 and 136.

Melting range 741: between 83 and 85.

Refractive index 831 : about 1.5609 at 20.

Assay— Inject an appropriate specimen (about 0.2 µL) into a suitable gas chromatograph (see Chromatography 621) equipped with a flame-ionization detector, helium being used as the carrier gas flowing at about 40 mL per minute. The following conditions have been found suitable: a 3-mm × 1.8-m stainless steel column containing 20% phase G16 on support S1A; the injection port temperature is maintained at 250; the column temperature is maintained at 50 and programmed to rise 10 per minute to 200. The detector temperature is maintained at 310. The area of the N,N-dimethylaniline peak having a retention time of about 11.5 minutes is not less than 99% of the total peak area.

Refractive index 831: between 1.5571 and 1.5591 at 20.

Boiling range (Reagent test)— Distill 100 mL: the difference between the temperatures observed, when 1 mL and 95 mL have distilled, is not more than 2.5. Its boiling temperature at a pressure of 760 mm of mercury is 194.2.

Hydrocarbons— Dissolve 5 mL in a mixture of 10 mL of hydrochloric acid and 15 mL of water: a clear solution results and it remains clear on cooling to about 10.

Aniline or monomethylaniline— Place 5 mL in a glass-stoppered flask, add 5 mL of a solution of acetic anhydride in benzene (1 in 10), mix, and allow to stand for 30 minutes. Add 30.0 mL of 0.5 N sodium hydroxide VS, shake the mixture, add phenolphthalein TS, and titrate with 0.5 N hydrochloric acid VS. Perform a blank determination, and make any necessary correction. Not more than 0.30 mL of 0.5 N sodium hydroxide is consumed by the test specimen.

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography 621) 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 phase G1: the detector temperature and the injection port temperature are maintained at 300; the column temperature is maintained at 180 and programmed to rise at the rate of 10 per minute to 280 and held at that temperature for 10 minutes. The area of the main peak is not less than 99% of the total peak area.

Melting range 741 : between 148 and 150.

Assay— Transfer about 250 mg, accurately weighed, to a suitable beaker, add 100 mL of glacial acetic acid, and dissolve by stirring. When solution is complete, titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 17.12 mg of C12H13N. Not less than 98% is found.

Refractive index 831: between 1.6210 and 1.6230 at 20, sodium light being used.

Sulfanilamide test— Dissolve 20 mg of USP Sulfanilamide RS in 100 mL of water to obtain the Sulfanilamide solution. Into two 150-mL beakers pipet 1.0 mL and 2.5 mL of the Sulfanilamide solution, respectively. Dilute with water to 90 mL. To provide a blank, place 90 mL of water in a third beaker. To each beaker add 8.0 mL of trichloroacetic acid solution (3 in 20) and 1.0 mL of sodium nitrite solution (1 in 1000). Stir the solutions for 5 minutes, then add 10 mL of acetate buffer TS, and 1.0 mL of a 1 in 1000 solution of N,N-dimethyl-1-naphthylamine in alcohol. The pH is about 5 to 6, using pH paper. Stir for an additional 5 minutes, then add 20 mL of glacial acetic acid. The pH is about 3 to 4, using pH paper. In comparison with the blank, the beaker containing 1.0 mL of the Sulfanilamide solution shows a pink color, while the other beaker shows a deep pink to red color.

Refractive index 831: 1.4243 at 20.

Assay— Inject a 1 in 3 solution of it in xylene into a suitable gas chromatograph equipped with a flame-ionization detector, helium being used as the carrier gas at a flow rate of about 40 mL per minute. The following conditions have been found suitable: a 3.2-mm × 1.83-m stainless steel column packed with 10% phase G25 on support S1A; the injection port is maintained at about 250 and the detector at about 310; the column temperature is programmed to rise at 8 per minute from 100 to 200. Similarly inject a specimen of xylene. The area of the C8H10O peak is not less than 98% of the total peak area corrected for xylene.

Melting range 741: between 44 and 46.

Assay— Transfer about 400 mg, accurately weighed, to a 250-mL beaker, and dissolve in about 75 mL of water. Titrate with 0.1 N sodium hydroxide VS, determining the endpoint potentiometrically. Each mL of 0.1 N sodium hydroxide is equivalent to 10.46 mg of C8H12N2·2HCl. Not less than 98% is found.

Solubility— A solution of 1 g in 10 mL of water produces not more than a slight haze.

Melting range 741 : between 89 and 92.

Residue on ignition (Reagent test): not more than 0.5%.

Melting range 741: between 69 and 71.

Solubility in sodium hydroxide— A solution of 500 mg in 25 mL of 1 N sodium hydroxide is clear or not more than faintly turbid.

Residue on ignition— Ignite 1 g with 0.5 mL of sulfuric acid: the residue weighs not more than 1 mg (0.1%).

Melting range 741: between 51 and 53.

Residue on ignition— Ignite 500 mg with 5 drops of sulfuric acid: the residue weighs not more than 1 mg (0.2%).

Melting range 741 : between 197 and 200.

Solubility in sulfuric acid— Dissolve 500 mg in a mixture of 25 mL of sulfuric acid and 25 mL of water: the solution is clear or not more than slightly turbid.

Residue on ignition (Reagent test): negligible, from 500 mg.

Melting range 741 : between 26 and 28.

Melting range 741: between 192 and 194.

Assay— Dissolve about 115 mg, accurately weighed, in 30 mL of methanol. Slowly add about 20 mL of water, heating slightly if necessary for complete solution. Titrate with 0.1 N sodium hydroxide VS, determining the endpoint potentiometrically. Perform a blank determination and make any necessary correction. Each mL of 0.1 N sodium hydroxide is equivalent to 22.73 mg of C14H13NO2. Not less than 98.0% is found.

Assay—

Refractive index 831: between 1.495 and 1.499 at 20.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography 621) 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 230; the detector temperature is maintained at 300; and the column temperature is maintained at 160 and programmed to rise 10 per minute to 260. The area of the C10H8N2·HCl peak is not less than 98.5% of the total peak area.

Melting range 741 : between 42 and 44.

Melting point 741 : higher than 300.