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Pentazocine Hydrochloride
C19H27NO·HCl 321.88

2,6-Methano-3-benzazocin-8-ol, 1,2,3,4,5,6-hexahydro-6,11-dimethyl-3-(3-methyl-2-butenyl)-, hydrochloride, (2,6,11R*)-.
(2R*,6R*,11R*)-1,2,3,4,5,6-Hexahydro-6,11-dimethyl-3-(3-methyl-2-butenyl)-2,6-methano-3-benzazocin-8-ol hydrochloride [64024-15-3].
» Pentazocine Hydrochloride contains not less than 98.0 percent and not more than 102.0 percent of C19H27NO·HCl, calculated on the dried basis.
Packaging and storage— Preserve in tight, light-resistant containers.
Identification—
Solution: 80 µg per mL of pentazocine.
Medium: 0.01 N hydrochloric acid.
Absorptivities at 278 nm, calculated on the dried basis, do not differ by more than 3.0%. [NOTE—The molecular weight of pentazocine (C19H27NO) is 285.43.]
B: Dissolve 50 mg of USP Pentazocine RS in 25 mL of 0.01 N hydrochloric acid in a separator, and use this in place of the Standard solution specified under Identification—Organic Nitrogenous Bases 181: Pentazocine Hydrochloride meets the requirements of the test.
C: A solution (1 in 100) responds to the tests for Chloride 191.
Loss on drying 731— Dry it at a pressure not exceeding 5 mm of mercury at 100 to constant weight: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.2%.
Ordinary impurities 466—
Test solution: methanol.
Standard solution: methanol, USP Pentazocine RS being used.
Eluant: a mixture of chloroform, methanol, and isopropylamine (94:3:3).
Visualization— Heat the plate in an oven at 105 for 15 minutes, cool, follow with visualization technique 17, and view under short-wavelength UV light.
Limits— The total of any ordinary impurities observed does not exceed 1.0%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— Dissolve about 650 mg of Pentazocine Hydrochloride, accurately weighed, in 50 mL of glacial acetic acid, and add 10 mL of mercuric acetate TS. Add 1 drop of crystal violet TS, and titrate with 0.1 N perchloric acid VS to a green endpoint. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 32.19 mg of C19H27NO·HCl.
Auxiliary Information— Staff Liaison : Clydewyn M. Anthony, Ph.D., Scientist
Expert Committee : (MDCCA05) Monograph Development-Cough Cold and Analgesics
USP29–NF24 Page 1673
Phone Number : 1-301-816-8139