Action and use<\/strong><\/p>\n Anticholinergic.<\/p>\n Preparations<\/strong><\/p>\n Oxybutynin Oral Solution<\/p>\n Oxybutynin Tablets<\/p>\n Oxybutynin Prolonged-release Tablets<\/p>\n 4-(Diethylamino)but-2-yn-1-yl (RS)-cyclohexyl(hydroxy)phenylacetate hydrochloride.<\/p>\n 99.0 per cent to 102.0 per cent (dried substance).<\/p>\n White or almost white, crystalline powder.<\/p>\n Freely soluble in water and in ethanol (96 per cent), soluble in acetone, practically insoluble in cyclohexane.<\/p>\n First identification: B, D.<\/p>\n Second identification: A, C, D.<\/p>\n A. Melting point (2.2.14): 124 \u00b0C to 129 \u00b0C.<\/p>\n B. Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison: oxybutynin hydrochloride CRS.<\/p>\n C. Thin-layer chromatography (2.2.27).<\/p>\n Test solution: Dissolve 50 mg of the substance to be examined in ethanol (96 per cent) R and dilute to 10 mL with the same solvent.<\/p>\n Reference solution: Dissolve 10 mg of oxybutynin hydrochloride CRS in ethanol (96 per cent) R and dilute to 2 mL with the same solvent.<\/p>\n Plate: TLC silica gel plate R.<\/p>\n Mobile phase: methanol R.<\/p>\n Application: 5 \u03bcL.<\/p>\n Development: Over 2\/3 of the plate.<\/p>\n Drying: In air.<\/p>\n Detection: Expose to iodine vapour for 30 min.<\/p>\n Results: The principal spot in the chromatogram obtained with the test solution is similar in position, colour and size to the principal spot in the chromatogram obtained with the reference solution.<\/p>\n D. It gives reaction (a) of chlorides (2.3.1).<\/p>\n Dissolve 2.00 g in water R and dilute to 20.0 mL with the same solvent.<\/p>\n Solution S is clear (2.2.1) and not more intensely coloured than reference solution BY5<\/sub> (2.2.2, Method II).<\/p>\n -0.10\u00b0 to + 0.10\u00b0, determined on solution S.<\/p>\n Liquid chromatography (2.2.29).<\/p>\n Test solution: Dissolve 50.0 mg of the substance to be examined in the mobile phase and dilute to 10.0 mL with the mobile phase.<\/p>\n Reference solution (a): Dissolve 5.0 mg of oxybutynin hydrochloride CRS and 5.0 mg of oxybutynin impurity A CRS in the mobile phase and dilute to 10.0 mL with the mobile phase. Dilute 5.0 mL of this solution to 50.0 mL with the mobile phase.<\/p>\n Reference solution (b): Dilute 1.0 mL of the test solution to 100.0 mL with the mobile phase. Dilute 1.0 mL of this solution to 10.0 mL with the mobile phase.<\/p>\n Reference solution (c): Dissolve 5 mg of oxybutynin hydrochloride for system suitability CRS (containing impurities C, D and F) in 1 mL of the mobile phase.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.15 m, \u00d8 = 3.9 mm;<\/p>\n \u2014 stationary phase: end-capped octylsilyl silica gel for chromatography R (5 \u03bcm);<\/p>\n \u2014 temperature: 35 \u00b0C.<\/p>\n Mobile phase: Mix 49 volumes of a solution containing 3.4 g\/L of potassium dihydrogen phosphate R and 4.36 g\/L of dipotassium hydrogen phosphate R and 51 volumes of acetonitrile R1.<\/p>\n Flow rate: 1 mL\/min.<\/p>\n Detection: Spectrophotometer at 210 nm.<\/p>\n Injection: 10 \u03bcL.<\/p>\n Run time: Twice the retention time of oxybutynin.<\/p>\n Identification of impurities: Use the chromatogram obtained with reference solution (a) to identify the peak due to impurity A; use the chromatogram supplied with oxybutynin hydrochloride for system suitability CRS and the chromatogram obtained with reference solution (c) to identify the peaks due to impurities C, D and F.<\/p>\n Relative retention: With reference to oxybutynin (retention time = about 15 min): impurity D = about 0.08; impurity F = about 0.7; impurity C = about 0.8; impurity A = about 1.6.<\/p>\n System suitability: Reference solution (c):<\/p>\n \u2014 resolution: minimum 2.0 between the peaks due to impurities F and C.<\/p>\n Calculation of percentage contents:<\/p>\n \u2014 correction factor: multiply the peak area of impurity D by 0.6;<\/p>\n \u2014 for impurity A, use the concentration of impurity A in reference solution (a);<\/p>\n \u2014 for impurities other than A, use the concentration of oxybutynin hydrochloride in reference solution (b).<\/p>\n Limits:<\/p>\n \u2014 impurity A: maximum 1.5 per cent;<\/p>\n \u2014 impurities C, D, F: for each impurity, maximum 0.15 per cent;<\/p>\n \u2014 unspecified impurities: for each impurity, maximum 0.10 per cent;<\/p>\n \u2014 sum of impurities other than A: maximum 0.5 per cent;<\/p>\n \u2014 reporting threshold: 0.05 per cent.<\/p>\n Maximum 3.0 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 5.0 mL of 0.01 M hydrochloric acid and 50 mL of ethanol (96 per cent) R.<\/p>\n Carry out a potentiometric titration (2.2.20), using 0.1 M sodium hydroxide. Read the volume added between the 2 points of inflexion.<\/p>\n 1 mL of 0.1 M sodium hydroxide is equivalent to 39.40 mg of C22<\/sub>H32<\/sub>ClNO3<\/sub>.<\/p>\n Protected from light.<\/p>\n Specified impurities A, C, D, F.<\/p>\n Other detectable impurities (the following substances would, if present at a sufficient level, be detected by one or other of the tests in the monograph. They are limited by the general acceptance criterion for other\/unspecified impurities and\/or by the general monograph Substances for pharmaceutical use (2034). It is therefore not necessary to identify these impurities for demonstration of compliance. See also 5.10. Control of impurities in substances for pharmaceutical use) B, E.<\/p>\n A. 4-(diethylamino)but-2-yn-1-yl (RS)-(cyclohex-1-en-1-yl)(cyclohexyl)hydroxyacetate,<\/p>\n B. 4-(diethylamino)but-2-yn-1-yl hydroxy(diphenyl)acetate (diphenyl analogue of oxybutynin),<\/p>\n C. 4-[ethyl(methyl)amino]but-2-yn-1-yl (RS)-cyclohexyl(hydroxy)phenylacetate (methylethyl analogue of oxybutynin),<\/p>\n D. (RS)-cyclohexyl(hydroxy)phenylacetic acid (cyclohexylphenylglycolic acid),<\/p>\n E. 4-[ethyl(propyl)amino]but-2-yn-1-yl (RS)-cyclohexyl(hydroxy)phenylacetate (ethylpropyl analogue of oxybutynin),<\/p>\n F. methyl (RS)-cyclohexyl(hydroxy)phenylacetate.<\/p>\n","protected":false},"excerpt":{"rendered":" (Ph. Eur. monograph 1354) C22H32ClNO3\u00a0 \u00a0 \u00a0 394.0\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 1508-65-2 Action and use Anticholinergic. Preparations Oxybutynin Oral Solution Oxybutynin Tablets Oxybutynin Prolonged-release Tablets DEFINITION 4-(Diethylamino)but-2-yn-1-yl (RS)-cyclohexyl(hydroxy)phenylacetate hydrochloride. Content 99.0 per cent to 102.0 per cent (dried substance). CHARACTERS Appearance White or almost white, crystalline powder. Solubility Freely soluble in water and…<\/p>\n","protected":false},"author":2,"featured_media":26087,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26064","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\/26064","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=26064"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26064\/revisions"}],"predecessor-version":[{"id":26091,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26064\/revisions\/26091"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26087"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26064"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26064"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26064"}],"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
Optical rotation (2.2.7)<\/h4>\n
Related substances<\/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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