Antazoline Phosphate

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

DOWNLOAD PDF HERE

C₁₇H₁₉N₃ · H₃PO₄       363.35

1H-Imidazole-2-methanamine, 4,5-dihydro-N-phenyl-N-(phenylmethyl)-, phosphate (1:1); 2-[(N-Benzylanilino)methyl]-2-imidazoline phosphate (1:1)  CAS RN: 154-68-7; UNII: VPR5FPH326.

1 DEFINITION

Antazoline Phosphate contains NLT 98.0% and NMT 102.0% of antazoline phosphate (C, H, N, H₃PO₄), calculated on the dried basis.

2 IDENTIFICATION

Change to read:

A. SPECTROSCOPIC IDENTIFICATION TESTS (197), Infrared Spectroscopy: 197M _{(CN 1-Mar-2020)}

B. The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.

3 ASSAY

PROCEDURE

Solution A: Dilute 1.0 mL of formic acid with water to 1000 mL.

Mobile phase: Acetonitrile and Solution A (17:83)

Diluent: Acetonitrile and water (17:83)

Standard solution: 0.2 mg/mL of USP Antazoline Phosphate RS in Diluent

System suitability solution: 1 µg/ml of USP Antazoline Related Compound A RS in the Standard solution

Sample solution: 0.2 mg/mL of Antazoline Phosphate in Diluent

Chromatographic system

(See Chromatography (621), System Suitability.)

Mode: LC

Detector: UV 240 nm.

Column: 2.1-mm x 10-cm; 1.7-µm packing L11

Temperatures

Column: 35

Autosampler: 4"

Flow rate: 0.5 mL/min

Injection volume: 5 µL

System suitability

Samples: Standard solution and System suitability solution

[NOTE-The relative retention times of antazoline and antazoline related compound A are 1.0 and 1.1, respectively.]

Suitability requirements

Resolution: NLT 2.0 between antazoline and antazoline related compound A, System suitability solution

Tailing factor: NMT 1.5 for antazoline, Standard solution

Relative standard deviation: NMT 0.73% for antazoline, Standard solution

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of antazoline phosphate (C₁₇H₁₉N₃ · H₃PO₄) in the portion of Antazoline Phosphate taken:

Result = (r_u /r_s ) × (C_s /C_u ) × 100

r_u = peak response from the Sample solution

r_s = peak response from the Standard solution

C_s = concentration of USP Antazoline Phosphate RS in the Standard solution (mg/mL)

C_u = concentration of Antazoline Phosphate in the Sample solution (mg/mL)

Acceptance criteria: 98.0%–102.0% on the dried basis

4 IMPURITIES

ORGANIC IMPURITIES

Solution A: Dilute 1.0 ml. of formic acid with water to 1000 mL.

Mobile phase: Acetonitrile and Solution A (17:83)

Diluent: Acetonitrile and water (17:83)

Standard solution A: 5 µg/mL of USP Antazoline Related Compound A RS and 1.0 mg/mL of USP Antazoline Phosphate RS in Diluent

Standard solution B: 1 µg/ml. of USP Antazoline Phosphate RS in Diluent

Sample solution: 1.0 mg/ml. of Antazoline Phosphate in Diluent

Chromatographic system

(See Chromatography (621), System Suitability,)

Mode: LC

Detector: UV 240 nm.

Column: 2.1-mm x 10-cm; 1.7-µm packing L11

Temperatures

Column: 35°

Autosampler: 4"

Flow rate: 0.5 mL/min

Injection volume: 5 µL

Run time: NLT 4 times the retention time of antazoline

System suitability

Samples: Standard solution A and Standard solution B

[NOTE-The relative retention times of antazoline and antazoline related compound A are 1.0 and 1.1, respectively]

Suitability requirements

Resolution: NLT 2.0 between antazoline and antazoline related compound A peaks, Standard solution A

Relative standard deviation: NMT 5.0% for antazoline, Standard solution B

Analysis

Samples: Standard solution A, Standard solution B, and Sample solution

Calculate the percentage of antazoline related compound A in the portion of Antazoline Phosphate taken:

Result = (r_u /r_s ) × (C_s /C_u ) × 100

r_u = peak response of antazoline related compound A from the Sample solution

r_s = peak response of antazoline related compound A from Standard solution A

C_s = concentration of USP Antazoline Related Compound A RS in Standard solution A (mg/mL)

C_u = concentration of Antazoline Phosphate in the Sample solution (mg/mL)

Calculate the percentage of any individual unspecied impurity in the portion of Antazoline Phosphate taken:

Result = (r_u /r_s ) × (C_s /C_u ) × 100

r_u = peak response of any impurity from the Sample solution

r_s = peak response of antazoline phosphate from Standard solution B

C_s = concentration of USP Antazoline Related Compound A RS in Standard solution A (mg/mL)

C_u = concentration of Antazoline Phosphate in the Sample solution (mg/mL)

Acceptance criteria: See Table 1. Disregard any impurity peaks less than 0.05%.

Table 1

^a N-(2-Aminoethyl)-2-[benzyl(phenyl)amino]acetamide.

5 SPECIFIC TESTS

pH 〈791〉

Sample: 20 mg/mL

Acceptance criteria: 4.0–5.0

Loss on Drying 〈731〉

Analysis: Dry at 105° for 4 h.

Acceptance criteria: NMT 0.5%

ADDITIONAL REQUIREMENTS

Packaging and Storage: Preserve in tight containers.

USP Reference Standards 〈11〉

USP Antazoline Phosphate RS

USP Antazoline Related Compound A RS

N-(2-Aminoethyl)-2-[benzyl(phenyl)amino]acetamide.

C₁₇H₂₁N₃O              283.38