Acetic acid, [[2-(diethylaminoethyl]thio]-, 6-ethenyl-decahydro-5-hydroxy-4,6,9,10-tetramethyl-1-oxo-3a,9-propano-3aH-cyclopentacycloocten-8-yl ester [3aS-(3a ,4 ,5 ,6 ,8 ,9 ,9a ,10S*)]-, (E)-2-butenedioate (1:1) (salt).
[[2-(Diethylamino)ethyl]thio]acetic acid 8-ester with (3aS,4R,5S,6S,8R,9R,9aR,10R)-octahydro-5,8-dihydroxy-4,6,9,10-tetramethyl-6-vinyl-3a,9-propano-3aH-cyclopentacycloocten-1(4H)-one fumarate (1:1) (salt) [55297-96-6].
» Tiamulin Fumarate contains not less than 97.0 percent and not more than 102.0 percent of C28H47NO4S·C4H4O4, calculated on the dried basis.
USP Tiamulin Related Compound A RS .
Color and clarity of solution— Transfer about 5.0 g of Tiamulin Fumarate to a 100-mL volumetric flask, and dissolve in and dilute with water to volume: the solution is clear and colorless, and the absorbance of the solution, determined in a 1-cm cell at 400 and 650 nm, is not greater than 0.150 and 0.030 absorbance units, respectively.
B: The retention time of the tiamulin fumarate peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Melting temperature 741 : between 143 and 152 .
Specific rotation 781S : between +24 and +28 , on the dried basis, measured at 20 .
Test solution: 5.0 mg per mL, in dioxane.
pH 791 : between 3.1 and 4.1.
Test solution: 1.0 g per 100 mL of water.
Internal standard solution— Dilute 0.3 mL of n-butanol to 1000 mL.
Standard solution— Transfer about 500 mg each of acetone, ethyl acetate, and isobutyl acetate, each accurately weighed, to a 250-mL volumetric flask, dilute with the Internal standard solution to volume, and mix. Transfer 2.5 mL of the solution so obtained to a 20-mL volumetric flask, dilute with the Internal standard solution to volume, and mix.
Test solution— Transfer about 1 g of Tiamulin Fumarate, accurately weighed, to a 20-mL volumetric flask, dissolve in and dilute with the Internal standard solution to volume, and mix.
Chromatographic system (see Chromatography 621 )— The gas chromatograph is equipped with a flame-ionization detector and a 0.25-mm × 30-m capillary column coated with a 0.5-µm film of phase G16. The carrier gas is helium, flowing at a rate of 1.07 mL per minute, and the split flow ratio is 50:1. The column temperature is maintained at 75 , the injection port temperature is maintained at 250 , and the detector temperature is maintained at 300 . Chromatograph the Standard solution, and record the peak responses as directed for Procedure: the relative retention times are about 0.34, 0.38, 0.57, and 1.0 for acetone, ethyl acetate, isobutyl acetate, and n-butanol, respectively; the resolution, R, between acetone and ethyl acetate is not less than 2.0; the tailing factor for each of the analyte peaks is not more than 2; and the relative standard deviation for replicate injections is not more than 2%.
in which WS is the weight, in mg, of the solvent of interest taken to prepare the Standard solution; WU is the weight, in mg, of Tiamulin Fumarate taken to prepare the Test solution; and RU and RS are the peak response ratios of the solvent of interest to the internal standard obtained from the Test solution and the Standard solution, respectively: not more than 0.5% each of acetone, ethyl acetate, and isobutyl acetate is found; and the sum of the percentages of acetone, ethyl acetate, and isobutyl acetate is not more than 0.5%.
Dilute perchloric acid solution, Buffer solution, Mobile phase, System suitability solution, and Chromatographic system— Proceed as directed in the Assay.
in which ri and rU are the peak responses of each impurity and tiamulin fumarate, respectively: not more than 1.0% of any identified impurity is found; not more than 0.5% of any unidentified impurity is found; and not more than 3.0% of total impurities is found.
Content of fumarate— Dissolve about 450 mg of Tiamulin Fumarate, accurately weighed, in 60 mL of a mixture of alcohol and water (1:1). Titrate with 0.1 N sodium hydroxide VS, determining the endpoint potentiometrically, using a glass–calomel electrode (see Titrimetry 541 ). Perform a blank determination, and make any necessary correction. Each mL of 0.1 N sodium hydroxide is equivalent to 5.8 mg of fumarate: between 83.7 and 87.3 mg of fumarate is found.
Dilute perchloric acid solution— Prepare a solution containing 6% of perchloric acid.
Buffer solution— Transfer 10 g of ammonium carbonate to a 1000-mL volumetric flask, and dissolve in about 800 mL of water. Add 24 mL of Dilute perchloric acid solution, dilute with water to volume, mix, and filter.
Mobile phase— Prepare a mixture of methanol, Buffer solution, and acetonitrile, (49:28:23), filter, and degas.
System suitability solution— Dissolve accurately weighed quantities of USP Tiamulin Fumarate RS and USP Tiamulin Related Compound A RS in Mobile phase to obtain a solution having known concentrations of about 0.08 mg of each per mL.
Standard preparation— Dissolve an accurately weighed quantity of USP Tiamulin Fumarate RS in Mobile phase to obtain a solution having a known concentration of about 4 mg per mL.
Assay preparation— Transfer about 200 mg of Tiamulin Fumarate, accurately weighed, to a 50-mL volumetric flask, dissolve in and dilute with Mobile phase to volume, and mix.
Chromatographic system (see Chromatography 621 )— The liquid chromatograph is equipped with a 212-nm detector and a 4.6-mm × 25-cm column that contains 5-µm packing L1. The flow rate is about 1.2 mL per minute. The column temperature is maintained at 30 ± 3 . Chromatograph the Standard preparation and the System suitability solution, and record the peak responses as directed for Procedure: the tiamulin related compound A peak elutes prior to the tiamulin fumarate peak; the resolution, R, between tiamulin related compound A and tiamulin fumarate is not less than 2.0; the capacity factor, k¢, determined from the tiamulin fumarate peak, is not less than 2.0; the column efficiency is not less than 14,000 theoretical plates; the tailing factor is not more than 2.0; and the relative standard deviation for replicate injections is not more than 2.0%.
in which C is the concentration, in mg per mL, of USP Tiamulin Fumarate RS in the Standard preparation; and rU and rS are the tiamulin fumarate peak responses obtained from the Assay preparation and the Standard preparation, respectively.