{"id":29627,"date":"2025-11-10T17:53:09","date_gmt":"2025-11-10T10:53:09","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=29627"},"modified":"2025-11-13T16:27:24","modified_gmt":"2025-11-13T09:27:24","slug":"tiabendazole","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/tiabendazole\/","title":{"rendered":"Tiabendazole"},"content":{"rendered":"

(Ph. Eur. monograph 0866)<\/p>\n

C10<\/sub>H7<\/sub>N3<\/sub>S 201.2 148-79-8<\/p>\n

Action and use<\/strong><\/p>\n

Benzimidazole antihelminthic.<\/p>\n

DEFINITION<\/h2>\n

Tiabendazole contains not less than 98.0 per cent and not more than the equivalent of 101.0 per cent of 2-(thiazol-4-yl)-1H-benzimidazole, calculated with reference to the anhydrous substance.<\/p>\n

CHARACTERS<\/h2>\n

A white or almost white, crystalline powder, practically insoluble in water, slightly soluble in ethanol (96 per cent) and in methylene chloride. It dissolves in dilute mineral acids. It melts at about 300 \u00b0C.<\/p>\n

IDENTIFICATION<\/h2>\n

First identification: B.<\/p>\n

Second identification: A, C, D.<\/p>\n

A. Dissolve 25 mg in 0.1 M hydrochloric acid and dilute to 100.0 mL with the same acid. Dilute 2.0 mL of the solution to 100.0 mL with 0.1 M hydrochloric acid. Examined between 230 nm and 350 nm (2.2.25), the solution shows two absorption maxima, at 243 nm and 302 nm. The ratio of the absorbance measured at the maximum at 302 nm to that measured at the maximum at 243 nm is 1.8 to 2.1.<\/p>\n

B. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrum obtained with tiabendazole CRS. Examine the substances prepared as discs.<\/p>\n

C. Examine the chromatograms obtained in the test for related substances in ultraviolet light at 254 nm. The principal spot in the chromatogram obtained with test solution (b) is similar in position and size to the principal spot in the chromatogram obtained with reference solution (a).<\/p>\n

D. Dissolve about 5 mg in 0.1 M hydrochloric acid and dilute to 5 mL with the same acid. Add 3 mg of p-phenylenediamine dihydrochloride R and shake until dissolved. Add 0.1 g of zinc powder R, mix, allow to stand for 2 min and add 5 mL of ferric ammonium sulfate solution R2. A bluish-violet colour develops.<\/p>\n

TESTS<\/h2>\n

Related substances<\/h3>\n

Examine by thin-layer chromatography (2.2.27), using silica gel HF254 R as the coating substance.<\/p>\n

Test solution (a)<\/em> Dissolve 0.10 g of the substance to be examined in methanol R and dilute to 10 mL with the same solvent.<\/p>\n

Test solution (b)<\/em> Dilute 2 mL of test solution (a) to 20 mL with methanol R.<\/p>\n

Reference solution (a)<\/em> Dissolve 20 mg of tiabendazole CRS in methanol R and dilute to 20 mL with the same solvent.<\/p>\n

Reference solution (b)<\/em> Dilute 1 mL of test solution (b) to 10 mL with methanol R.<\/p>\n

Reference solution (c)<\/em> Dilute 1 mL of test solution (b) to 25 mL with methanol R.<\/p>\n

Apply separately to the plate 20 \u03bcL of each solution. Develop over a path of 15 cm using a mixture of 2.5 volumes of water R, 10 volumes of acetone R, 25 volumes of glacial acetic acid R and 62.5 volumes of toluene R. Allow the plate to dry in air and examine in ultraviolet light at 254 nm. Any spot in the chromatogram obtained with test solution (a), apart from the principal spot, is not more intense than the spot in the chromatogram obtained with reference solution (b) (1.0 per cent) and at most one such spot is more intense than the spot in the chromatogram obtained with reference solution (c) (0.4 per cent).<\/p>\n

o-Phenylenediamine<\/h3>\n

To 5.0 g in a flask fitted with a ground-glass stopper, add 25 mL of a mixture of 1 volume of methanol R and 2 volumes of water R. Shake for 3 min. Filter through a sintered-glass filter (16) (2.1.2) under reduced pressure. To 10 mL of the filtrate add 0.5 mL of hydrochloric acid R and 0.5 mL of acetylacetone R and shake until the solution is clear. The solution is not more intensely coloured than reference solution R7 (2.2.2, Method I) (10 ppm).<\/p>\n

Water (2.5.12)<\/h3>\n

Not more than 0.5 per cent, determined on 1.00 g by the semi-micro determination of water.<\/p>\n

Sulfated ash (2.4.14)<\/h3>\n

Not more than 0.2 per cent, determined on 1.0 g.<\/p>\n

ASSAY<\/h2>\n

Dissolve 0.150 g in 30 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 20.12 mg of C10<\/sub>H7<\/sub>N3<\/sub>S.<\/p>\n

STORAGE<\/h2>\n

Store protected from light.<\/p>\n

IMPURITIES<\/h2>\n

\"Tiabendazole\"
\nA. benzene-1,2-diamine.<\/p>\n","protected":false},"excerpt":{"rendered":"

(Ph. Eur. monograph 0866) C10H7N3S 201.2 148-79-8 Action and use Benzimidazole antihelminthic. DEFINITION Tiabendazole contains not less than 98.0 per cent and not more than the equivalent of 101.0 per cent of 2-(thiazol-4-yl)-1H-benzimidazole, calculated with reference to the anhydrous substance. CHARACTERS A white or almost white, crystalline powder, practically insoluble in water, slightly soluble in…<\/p>\n","protected":false},"author":5,"featured_media":29629,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-29627","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\/29627","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=29627"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29627\/revisions"}],"predecessor-version":[{"id":29632,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29627\/revisions\/29632"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/29629"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=29627"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=29627"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=29627"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}