Azithromycin CAS NO.83905-01-5

ests

Acceptance Criteria

Results

Characters

white or almost white crystalline powder, no order and bitter. Practically insoluble in water, freely soluble in anhydrous ethanol and in methylene chloride

Conforms

Identification

(1)   IR: Conforms to the Azithromycin RS spectrum

(2)   HPLC: The retention time of azithromycin peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay

Conforms

Specific rotation

-45°~-49°(Anhydrous subatance 20mg/ml dehydrated alcohol)

-47°

Crystallinity

Meets the requirement

Conforms

PH

9.0~11.0(2mg/ml methanol-water(1:1))

10.1

Water

4.0%~5.0%

4.3%

Residue on Ignition

≤0.3%

0.02%

Heavy metals

≤0.0025%

less 0.0025%

Related substances

(HPLC)

(1) desosaminylazithromycin

≤0.3%

0.02%

N-demethylazithromycin

≤0.7%

0.44%

(2) Any other impurity

≤1.0%

0.84%

(3) Total impurity

≤3.0%

1.6%

Residual solvents

Methylene Clloride

≤600ppm

Not detected

Acetone

≤5000ppm

1306.5ppm

Assay(HPLC)

945~1030μg/mg (Anhydrous substance)

966μg/mg

Conclusion

Conforms to USP32 specification for Azithromycin