Action and use<\/strong><\/p>\n Opioid analgesic.<\/p>\n (6R)-6-(Dimethylamino)-4,4-diphenylheptan-3-one hydrochloride.<\/p>\n 99.0 per cent to 101.0 per cent (dried substance).<\/p>\n White or almost white, crystalline powder.<\/p>\n Soluble in water, freely soluble in ethanol (96 per cent).<\/p>\n First identification: A, C, D.<\/p>\n Second identification: A, B, D.<\/p>\n A. Specific optical rotation (see Tests).<\/p>\n B. Melting point (2.2.14): 239 \u00b0C to 242 \u00b0C.<\/p>\n C. Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison: Ph. Eur. reference spectrum of methadone hydrochloride.<\/p>\n D. Dilute 1 mL of solution S (see Tests) to 5 mL with water R and add 1 mL of dilute ammonia R1. Mix, allow to stand for 5 min and filter. The filtrate gives reaction (a) of chlorides (2.3.1).<\/p>\n Dissolve 2.50 g in carbon dioxide-free water R and dilute to 50.0 mL with the same solvent.<\/p>\n Solution S is clear (2.2.1) and colourless (2.2.2, Method II).<\/p>\n Dilute 10 mL of solution S to 25 mL with carbon dioxide-free water R. To 10 mL of the solution add 0.2 mL of methyl red solution R and 0.2 mL of 0.01 M sodium hydroxide. The solution is yellow. Add 0.4 mL of 0.01 M hydrochloric acid. The solution is red.<\/p>\n -125 to -135 (dried substance), determined on solution S.<\/p>\n Liquid chromatography (2.2.29).<\/p>\n Test solution: Dissolve 25.0 mg of the substance to be examined in the mobile phase and dilute to 100.0 mL with the mobile phase.<\/p>\n Reference solution (a): Dilute 1.0 mL of the test solution to 50.0 mL with the mobile phase. Dilute 1.0 mL of the solution to 10.0 mL with the mobile phase.<\/p>\n Reference solution (b): Dissolve 12.0 mg of imipramine hydrochloride CRS in the mobile phase and dilute to 10 mL with the mobile phase. To 1 mL of the solution add 5 mL of the test solution and dilute to 10 mL with the mobile phase.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.125 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: octadecylsilyl silica gel for chromatography R (5 \u03bcm);<\/p>\n \u2014 temperature: 25 \u00b0C.<\/p>\n Mobile phase: Mix 35 volumes of acetonitrile R and 65 volumes of an 11.5 g\/L solution of phosphoric acid R adjusted to pH 3.6 with tetraethylammonium hydroxide solution R.<\/p>\n Flow rate: 1.0 mL\/min.<\/p>\n Detection: Spectrophotometer at 210 nm.<\/p>\n Equilibration: About 30 min.<\/p>\n Injection: 10 \u03bcL.<\/p>\n Run time: 7 times the retention time of levomethadone.<\/p>\n Retention time: Levomethadone = about 5 min.<\/p>\n System suitability: Reference solution (b):<\/p>\n \u2014 resolution: minimum 2.5 between the peaks due to imipramine and levomethadone.<\/p>\n Limits:<\/p>\n \u2014 any impurity: not more than 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.1 per cent);<\/p>\n \u2014 total: not more than 2.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.5 per cent);<\/p>\n \u2014 disregard limit: 0.25 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.05 per cent).<\/p>\n Liquid chromatography (2.2.29).<\/p>\n Test solution: Dissolve 40.0 mg of the substance to be examined in the mobile phase and dilute to 100.0 mL with the mobile phase.<\/p>\n Reference solution: Dilute 1.0 mL of the test solution to 10.0 mL with the mobile phase. Dilute 1.0 mL of this solution to 20.0 mL with the mobile phase.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.25 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: 2-hydroxypropylbetadex for chromatography R (5 \u03bcm);<\/p>\n \u2014 temperature: 10 \u00b0C.<\/p>\n Mobile phase: Mix 1 volume of triethylamine R adjusted to pH 4.0 with phosphoric acid R, 15 volumes of acetonitrile R and 85 volumes of a 13.6 g\/L solution of potassium dihydrogen phosphate R.<\/p>\n Flow rate: 0.7 mL\/min.<\/p>\n Detection: Spectrophotometer at 210 nm.<\/p>\n Equilibration: About 30 min.<\/p>\n Injection: 10 \u03bcL.<\/p>\n Relative retention: With reference to levomethadone: dextromethadone = about 1.4.<\/p>\n System suitability: Test solution:<\/p>\n \u2014 number of theoretical plates: minimum 2000, calculated for the peak due to levomethadone;<\/p>\n \u2014 tailing factor: maximum 3 for the peak due to levomethadone.<\/p>\n Limit:<\/p>\n \u2014 dextromethadone: not more than the area of the principal peak in the chromatogram obtained with the reference solution (0.5 per cent).<\/p>\n Maximum 0.5 per cent, determined on 1.000 g by drying in an oven at 105 \u00b0C.<\/p>\n Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n Dissolve 0.300 g in a mixture of 40 mL of water R and 5 mL of acetic acid R. Titrate with 0.1 M silver nitrate. Determine the end-point potentiometrically (2.2.20), using a silver electrode.<\/p>\n 1 mL of 0.1 M silver nitrate is equivalent to 34.59 mg of C21<\/sub>H28<\/sub>ClNO.<\/p>\n Protected from light.<\/p>\n Specified impurities A, B, C, D, E, F.<\/p>\n A. (6S)-6-(dimethylamino)-4,4-diphenylheptan-3-one,<\/p>\n B. (4RS)-4-(dimethylamino)-2,2-diphenylpentanenitrile,<\/p>\n C. (3RS)-4-(dimethylamino)-3-methyl-2,2-diphenylbutanenitrile,<\/p>\n D. (5RS)-6-(dimethylamino)-5-methyl-4,4-diphenylhexan-3-one,<\/p>\n E. diphenylacetonitrile,<\/p>\n F. (2S)-2-[[(4-methylphenyl)sulfonyl]amino]pentanedioic acid (N-p-tosyl-L-glutamic acid).<\/p>\n","protected":false},"excerpt":{"rendered":" (Ph. Eur. monograph 1787) C21H28ClNO\u00a0 \u00a0 \u00a0 \u00a0345.9\u00a0 \u00a0 \u00a0 \u00a0 5967-73-7 Action and use Opioid analgesic. DEFINITION (6R)-6-(Dimethylamino)-4,4-diphenylheptan-3-one hydrochloride. Content 99.0 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, crystalline powder. Solubility Soluble in water, freely soluble in ethanol (96 per cent). IDENTIFICATION First identification: A, C, D….<\/p>\n","protected":false},"author":2,"featured_media":16972,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-16944","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicinal-substances"],"acf":[],"_links":{"self":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/16944","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=16944"}],"version-history":[{"count":3,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/16944\/revisions"}],"predecessor-version":[{"id":16975,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/16944\/revisions\/16975"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/16972"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=16944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=16944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=16944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}DEFINITION<\/h2>\n
Content<\/h3>\n
CHARACTERS<\/h2>\n
Appearance<\/h3>\n
Solubility<\/h3>\n
IDENTIFICATION<\/h2>\n
TESTS<\/h2>\n
Solution S<\/h3>\n
Appearance of solution<\/h3>\n
Acidity or alkalinity<\/h3>\n
Specific optical rotation (2.2.7)<\/h4>\n
Related substances<\/h3>\n
Dextromethadone<\/h3>\n
Loss on drying (2.2.32)<\/h4>\n
Sulfated ash (2.4.14)<\/h4>\n
ASSAY<\/h2>\n
STORAGE<\/h2>\n
IMPURITIES<\/h2>\n
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