Calcipotriol

Appearance 

White or almost white, crystalline powder

Complies

Solubility

Practically insoluble in water, freely soluble in ethanol,(96%), slightly soluble in methylene chloride

(96 percent), slightly soluble in methylene chloride

Complies

Identification

Infrared spectrum corresponds to that of the standard preparation

Complies

The retention time of the major peak in the

chromatogram corresponds to that in the chromatogram of standard preparation

Complies

Related Substances by TLC

Impurity A ((5Z,7E,22E)-24-cyclopropyl-1α,3β-dihydroxy-9,10-secochola-5,7,10(19),22-tetraen-24-one): NMT 0.25%

Complies

Impurity G  (24,24-oxybis[(5Z,7E,22E,24S)-24-cyclopropyl-9,10-secochola-5,7,10(19),22-tetraene-1α,3β-diol]) : NMT 0.25%

Complies

Impurity H ((5Z,7E,22E,24R)-24-cyclopropyl-24-

[[(5Z,7E,22E,24S)-24-cyclopropyl-1α,3β-dihydroxy-9,10-secochola-5,7,10(19),22-tetraen-24-yl]oxy]-9,10-secochola-5,7,10(19),22-tetraene-1α,3β-diol): NMT 0.25%

Complies

Any other impurity : NMT 0.1%

Complies

Related Substances by HPLC

Impurity B ((7Z)-calcipotriol) : NMT 0.5%

ND

Impurity C ((5E)-calcipotriol) : NMT 1.0%

0.50%

Impurity D (24-epi-calcipotriol) : NMT 1.0%

0.66%

Any other impurity: NMT 0.1%

0.09%

Total impurities : NMT 2.5%

1.25%

Residual Solvents

Acetone : NMT 5000ppm

630ppm

Ethyl acetate : NMT 5000ppm

ND

n-Hexane : NMT 290ppm

ND

Methanol : NMT 3000ppm

ND

Dichloromethane : NMT 600ppm

ND

Loss on Drying

NMT 0.5%

0.27%

Content

95.5%-102.0% (dried substance)

98.26%