Molecular formula. C₁₄H₂₄N₂O₇,2HCl,5H₂O

Relative molecular mass. 495.4

Graphic formula

Chemical name. (2R,4aR,5aR,6S,7S,8R,9S,9aR,10aS)-Decahydro-4a,7,9-trihydroxy-2-methyl-6,8-bis(methylamino)-4H-pyrano[2,3-b][1,4]benzodioxin-4-one dihydrochloride pentahydrate; [2R-(2α,4aβ,5aβ,6β,7β,8β,9α,9aα,10aβ)]-decahydro-4a,7,9-trihydroxy-2-methyl-6,8-bis(methylamino)-4H-pyrano[2,3-b][1,4] benzodioxin-4-one dihydrochloride pentahydrate; CAS Reg. No. 22189-32-8 (pentahydrate).

Description. A white or almost white, crystalline powder; odourless.

Solubility. Freely soluble in water; practically insoluble in ethanol (~750 g/L) TS and ether R.

Category. Antibacterial drug.

Storage. Spectinomycin hydrochloride should be kept in a well-closed container.

Manufacture. The substance is produced by methods of manufacture designed to eliminate or minimize substances lowering blood pressure.

Requirements

Definition. Spectinomycin hydrochloride contains not less than 600 μg of C₁₄H₂₄N₂O₇ per mg, calculated with reference to the anhydrous substance.

Identity tests

1. Carry out the examination as described under 1.7 Spectrophotometry in the infrared region. The infrared absorption spectrum is concordant with the spectrum obtained from Spectinomycin hydrochloride RS or with the reference spectrum of Spectinomycin hydrochloride.

2. A 20 mg/mL solution yields reaction B described under 2.1 General identification tests as characteristic of chlorides.

Specific optical rotation. Use a 0.10 g/mL solution and calculate with reference to the anhydrous substance: = +15 to +21.

Sulfated ash. Not more than 10 mg/g.

Water. Determine as described under 2.8 Determination of water by the Karl Fischer method, Method A, using about 0.2 g of the substance; the water content is not less than 0.16 g/g and not more than 0.20 g/g.

pH value. pH of a 0.10 g/mL solution, 3.8–5.6.

Related substances

Carry out the test as described under 1.14.1 Chromatography, Thin-layer chromatography using silica gel R1 as the coating substance and a mixture of 10 volumes of 1-propanol R, 8 volumes of water, 1 volume of glacial acetic acid R and 1 volume of pyridine R as the mobile phase. Apply separately to the plate 10 μl of each of 2 solutions containing (A) 20 mg of the test substance per mL and (B) 0.20 mL of the test substance per mL. After removing the plate from the chromatographic chamber allow it to dry in air, spray it with potassium permanganate (25 g/L) TS, allow it to stand for 2–3 minutes and examine the chromatogram in daylight. Any spot obtained with solution A, other than the principal spot, is not more intense than that obtained with solution B.

Assay

Carry out the assay described under 1.14.1 Chromatography, Gas chromatography. As an internal standard use a solution containing 2 mg of triphenylantimony R per mL of dimethylformamide R. Use the following 2 solutions: (1) to about 30 mg of spectinomycin hydrochloride RS, accurately weighed, add 10.0 mL of the internal standard and 1.0 mL of hexamethyldisilazane R and shake intermittently for 1 hour; and (2) to 30 mg of the substance being examined add 10.0 mL of the internal standard and 1.0 mL of hexamethyldisilazane R and shake intermittently for 1 hour. For the procedure use a flame ionization detector and a glass column 1.3 m long and 0.4 cm in internal diameter packed with an adequate quantity of an adsorbent composed of 5 g of phenyl/methylpolysiloxane R supported on 95 g of acid-washed and base-washed, silanized kieselguhr R4. Maintain the column and the detector at about 215 °C and 270 °C, respectively, and the injection part at about 265 °C. Use dry helium R as the carrier gas at a flow rate of about 90 mL per minute. Prepare chromatogram A and B injecting separately about 2.5 μl of each of solutions 1 and 2. Measure the area of the major peak in each chromatogram and calculate the content in μg of C₁₄H₂₄N₂O₇ per mg in the substance being tested.

Additional requirement for Spectinomycin hydrochloride for parenteral use

Sterility. Complies with 3.2 Test for sterility.

Bacterial endotoxins. Carry out the test as described under 3.4 Test for bacterial endotoxins; contains not more than 0.09 IU of endotoxin RS per mg of spectinomycin.