Action and use<\/strong><\/p>\n Anabolic steroid; androgen.<\/p>\n 17-Methyl-2\u2032H-5\u03b1-androst-2-eno[3,2-c]pyrazol-17\u03b2-ol.<\/p>\n 98.5 per cent to 101.0 per cent (dried substance).<\/p>\n White or almost white, hygroscopic, crystalline powder.<\/p>\n Practically insoluble in water, soluble in dimethylformamide, slightly soluble in ethanol (96 per cent), very slightly soluble in methylene chloride.<\/p>\n It shows polymorphism (5.9).<\/p>\n A. Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison: stanozolol CRS.<\/p>\n If the spectra obtained in the solid state show differences, dissolve the substance to be examined and the reference substance separately in the minimum volume of methylene chloride R, evaporate to dryness at room temperature under an air-stream and record new spectra using the residues.<\/p>\n B. Liquid chromatography (2.2.29) as described in the test for related substances with the following modification.<\/p>\n Injection: Test solution and reference solution (c).<\/p>\n Results: The principal peak in the chromatogram obtained with the test solution is similar in retention time and size to the principal peak in the chromatogram obtained with reference solution (c).<\/p>\n + 37 to + 41 (dried substance).<\/p>\n Dissolve 60.0 mg in methanol R and dilute to 20.0 mL with the same solvent.<\/p>\n Thin-layer chromatography (2.2.27).<\/p>\n Solvent mixture: methanol R1, methylene chloride R (10:90 V\/V).]\n Test solution: Dissolve 20 mg of the substance to be examined in 1.0 mL of the solvent mixture.<\/p>\n Reference solution: Dissolve 2 mg of stanozolol CRS, 2.0 mg of stanozolol impurity A CRS and 2.0 mg of stanozolol impurity B CRS in 1.0 mL of the solvent mixture. Dilute 0.1 mL of the solution to 2.0 mL with the solvent mixture.<\/p>\n Plate: TLC silica gel plate R.<\/p>\n Mobile phase: glacial acetic acid R, ethyl acetate R, cyclohexane R (2:48:50 V\/V\/V).<\/p>\n Application: 10 \u03bcL.<\/p>\n Development: Over 3\/4 of the plate.<\/p>\n Drying: In air.<\/p>\n Detection: Spray with vanillin reagent R and heat at 120 \u00b0C.<\/p>\n System suitability: Reference solution:<\/p>\n \u2014 the chromatogram shows 3 clearly separated spots, due to stanozolol, impurity A and impurity B, in order of increasing RF value.<\/p>\n Limits:<\/p>\n \u2014 impurity A: any spot due to impurity A is not more intense than the corresponding spot in the chromatogram obtained with the reference solution (0.5 per cent);<\/p>\n \u2014 impurity B: any spot due to impurity B is not more intense than the corresponding spot in the chromatogram obtained with the reference solution (0.5 per cent).<\/p>\n Liquid chromatography (2.2.29).<\/p>\n Test solution: Dissolve 15.0 mg of the substance to be examined in methanol R and dilute to 5.0 mL with the same solvent.<\/p>\n Reference solution (a): Dilute 1.0 mL of the test solution to 100.0 mL with methanol R. Dilute 1.0 mL of this solution to 10.0 mL with methanol R.<\/p>\n Reference solution (b): Dissolve 1 mg of stanozolol CRS and 1 mg of stanozolol impurity B CRS in methanol R and dilute to 20 mL with the same solvent.<\/p>\n Reference solution (c): Dissolve 15.0 mg of stanozolol CRS in methanol R and dilute to 5.0 mL with the same solvent.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.15 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: end-capped octadecylsilyl silica gel for chromatography R1 (5 \u03bcm).<\/p>\n Mobile phase: 1 g\/L solution of sodium dihydrogen phosphate R adjusted to pH 3.0 with phosphoric acid R, methanol R1 (30:70 V\/V).<\/p>\n Flow rate: 1.5 mL\/min.<\/p>\n Detection: Spectrophotometer at 228 nm.<\/p>\n Injection: 25 \u03bcL of the test solution and reference solutions (a) and (b).<\/p>\n Run time: 3 times the retention time of stanozolol.<\/p>\n Identification of impurities: Use the chromatogram obtained with reference solution (b) to identify the peak due to<\/p>\n Relative retention: With reference to stanozolol (retention time = about 12 min): impurity B = about 1.3.<\/p>\n System suitability: Reference solution (b):<\/p>\n \u2014 resolution: minimum 4.0 between the peaks due to stanozolol and impurity B.<\/p>\n Limits:<\/p>\n \u2014 unspecified impurities: for each impurity, not more than 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) (0.5 per cent);<\/p>\n \u2014 disregard limit: 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.05 per cent).<\/p>\n Maximum 1.0 per cent, determined on 1.000 g by drying at 105 \u00b0C at a pressure not exceeding 0.7 kPa.<\/p>\n Dissolve 0.250 g in 50 mL of anhydrous acetic acid 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 32.85 mg of C21<\/sub>H32<\/sub>N2<\/sub>O.<\/p>\n In an airtight container, protected from light.<\/p>\n Specified impurities A, B.<\/p>\n A. 17\u03b2-hydroxy-17-methyl-5\u03b1-androstan-3-one (mestanolone),<\/p>\n B. 17\u03b2-hydroxy-2-(hydroxymethylene)-17-methyl-5\u03b1-androstan-3-one (oxymetholone).<\/p>\n","protected":false},"excerpt":{"rendered":" (Ph. Eur. monograph 1568) C21H32N2O\u00a0 \u00a0 \u00a0 \u00a0328.5\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 10418-03-8 Action and use Anabolic steroid; androgen. DEFINITION 17-Methyl-2\u2032H-5\u03b1-androst-2-eno[3,2-c]pyrazol-17\u03b2-ol. Content 98.5 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, hygroscopic, crystalline powder. Solubility Practically insoluble in water, soluble in dimethylformamide, slightly soluble in ethanol (96 per…<\/p>\n","protected":false},"author":2,"featured_media":30755,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-30751","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\/30751","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=30751"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/30751\/revisions"}],"predecessor-version":[{"id":30757,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/30751\/revisions\/30757"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/30755"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=30751"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=30751"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=30751"}],"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
Specific optical rotation (2.2.7)<\/h3>\n
Impurities A and B<\/h3>\n
Related substances<\/h3>\n
impurity B.<\/h3>\n
Loss on drying (2.2.32)<\/h4>\n
ASSAY<\/h2>\n
STORAGE<\/h2>\n
IMPURITIES<\/h2>\n
![\"Stanozolol\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Stanozolol-1-300x163.jpg\")
<\/p>\n![\"Stanozolol\"](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Stanozolol-2-300x163.jpg\")
<\/p>\n