Benzodiazepine.<\/p>\n
Preparation <\/strong><\/p>\n Oxazepam Tablets<\/p>\n Ph Eur<\/p>\n (3RS)-7-Chloro-3-hydroxy-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one.<\/p>\n Content<\/strong><\/p>\n 99.0 per cent to 101.0 per cent (dried substance).<\/p>\n White or almost white, crystalline powder.<\/p>\n Practically insoluble in water, slightly soluble in ethanol (96 per cent).<\/p>\n Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison\u00a0 oxazepam CRS.<\/em><\/p>\n Liquid chromatography (2.2.29). Prepare the solutions immediately before use.<\/p>\n Test solution\u00a0 Dissolve 40.0 mg of the substance to be examined in 25 mL of a mixture of equal volumes of acetonitrile R and water R and dilute to 50.0 mL with the same mixture of solvents.<\/p>\n Reference solution (a)\u00a0 Dilute 1.0 mL of the test solution to 100.0 mL with a mixture of equal volumes of acetonitrile R and water R. Dilute 2.0 mL of this solution to 10.0 mL with a mixture of equal volumes of acetonitrile R and water R.<\/p>\n Reference solution (b)\u00a0 Dissolve the contents of a vial of oxazepam for peak identification CRS (containing impurities A, B, C, D and E) in 1.0 mL of the test solution.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.25 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: end-capped octadecylsilyl silica gel for chromatography R (5 \u00b5m) resistant to bases up to pH 11.<\/p>\n Mobile phase:<\/p>\n \u2014 mobile phase A: dissolve 3.48 g of dipotassium hydrogen phosphate R in 900 mL of water R, adjust to pH 10.5 with a 40 g\/L solution of sodium hydroxide R and dilute to 1000 mL with water R;<\/p>\n \u2014 mobile phase B: acetonitrile R;<\/p>\n Flow rate\u00a0 1.0 mL\/min.<\/p>\n Detection\u00a0 Spectrophotometer at 235 nm.<\/p>\n Injection\u00a0 10 \u00b5L.<\/p>\n Identification of impurities\u00a0 Use the chromatogram obtained with reference solution (b) and the chromatogram supplied with oxazepam for peak identification CRS to identify the peaks due to impurities A, B, C, D and E.<\/p>\n Relative retention\u00a0 With reference to oxazepam (retention time = about 15 min): impurity E = about 0.7; impurity A = about 0.8; impurity B = about 1.2; impurity C = about 1.4; impurity D = about 2.0.<\/p>\n System suitability\u00a0 Reference solution (b):<\/p>\n \u2014 resolution: minimum 1.5 between the peaks due to impurities E and A.<\/p>\n Limits:<\/p>\n \u2014 correction factors: for the calculation of content, multiply the peak areas of the following impurities by the corresponding correction factor: impurity A = 4.0; impurity B = 1.1;<\/p>\n \u2014 impurities A, B, C, D, E: for each impurity, not more than the area of the principal peak in the chromatogram obtained with reference solution (a) (0.2 per cent);<\/p>\n \u2014 unspecified impurities: for each impurity, not more than 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.10 per cent);<\/p>\n \u2014 total: not more than 5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (1.0 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 Loss on drying (2.2.32)<\/strong><\/p>\n Maximum 0.5 per cent, determined on 1.000 g by drying in an oven at 105 \u00b0C at a pressure not exceeding 0.7 kPa.<\/p>\n Sulfated ash (2.4.14)<\/strong><\/p>\n Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n Dissolve 0.250 g in a mixture of 10 mL of anhydrous acetic acid R and 90 mL of acetic anhydride R. Titrate with 0.1 M perchloric acid, determining the end-point potentiometrically (2.2.20).<\/p>\n 1 mL of 0.1 M perchloric acid is equivalent to 28.67 mg of C15H11ClN2O2.<\/p>\n Protected from light.<\/p>\n Specified impurities\u00a0 A, B, C, D, E.<\/p>\n A. (5RS)-7-chloro-5-phenyl-4,5-dihydro-1H-1,4-benzodiazepine-2,3-dione,<\/p>\n B. (3RS)-7-chloro-2-oxo-5-phenyl-2,3-dihydro-1H-1,4-benzodiazepin-3-yl acetate,<\/p>\n C. 6-chloro-4-phenylquinazoline-2-carbaldehyde,<\/p>\n D. (2-amino-5-chlorophenyl)phenylmethanone,<\/p>\n E. 7-chloro-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one\u00a0 4-oxide.<\/p>\n Ph Eur<\/p>\n","protected":false},"excerpt":{"rendered":" Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Benzodiazepine. Preparation Oxazepam Tablets Ph Eur DEFINITION (3RS)-7-Chloro-3-hydroxy-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one. Content 99.0 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, crystalline powder. Solubility Practically insoluble in water, slightly soluble in ethanol (96 per cent). IDENTIFICATION Infrared absorption spectrophotometry (2.2.24). Comparison\u00a0 oxazepam…<\/p>\n","protected":false},"author":5,"featured_media":26879,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26878","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\/26878","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\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=26878"}],"version-history":[{"count":4,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26878\/revisions"}],"predecessor-version":[{"id":27407,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26878\/revisions\/27407"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26879"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26878"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26878"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26878"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nDEFINITION<\/h2>\n
CHARACTERS<\/h2>\n
Appearance<\/h3>\n
Solubility<\/h3>\n
IDENTIFICATION<\/h2>\n
TESTS<\/h2>\n
Related substances<\/h3>\n
\n\n
\n Time (min)<\/strong><\/td>\n Mobile phase A (per cent V\/V)<\/strong><\/td>\n Mobile phase B (per cent V\/V)<\/strong><\/td>\n<\/tr>\n \n 0 – 4<\/td>\n 75<\/td>\n 25<\/td>\n<\/tr>\n \n 4 – 34<\/td>\n 75 \u2192 25<\/td>\n 25 \u2192 75<\/td>\n<\/tr>\n \n 34 – 45<\/td>\n 25<\/td>\n 75<\/td>\n<\/tr>\n \n 45 – 50<\/td>\n 25 \u2192 75<\/td>\n 75 \u2192 25<\/td>\n<\/tr>\n \n 50 – 60<\/td>\n 75<\/td>\n 25<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n ASSAY<\/h2>\n
STORAGE<\/h2>\n
IMPURITIES<\/h2>\n
![\"Oxazepam\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Oxazepam-British-Pharmacopoeia-2025-1.jpg\")
<\/p>\n![\"Oxazepam\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Oxazepam-British-Pharmacopoeia-2025-2.jpg\")
<\/p>\n![\"Oxazepam\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Oxazepam-British-Pharmacopoeia-2025-3.jpg\")
<\/p>\n![\"Oxazepam\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Oxazepam-British-Pharmacopoeia-2025-4.jpg\")
<\/p>\n![\"Oxazepam\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Oxazepam-British-Pharmacopoeia-2025-5.jpg\")
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