Name: Clobetasone Butyrate BP

T.S.No.: SPEC/API/HCB-015/B/01
Issue Date: 01/03/2006

Code: HCB

CAS: 25122-57-0

Storage: Store protected from light.

Supersede: SPEC/API/HCB-015/B
Date: 01/04/2002

M.F.:  C26 H32 ClFO5

M.W.: 479.00  g/mole







A white or almost white powder.



Practically insoluble in water, freely soluble in acetone and in methylene chloride, slightly soluble in alcohol.

Identification A


The Infra red absorption spectrum should concordant with the spectrum obtained from working std of clobetasone butyrate with the Reference Infra red spectrum graph.

Identification B


The principal spot in the chromatogram obtained with the test solution be  similar in position and size to the principal spot in the chromatogram obtained with reference solution (a).The test should not valid unless the chromatogram obtained with reference solution (b) should show two clearly separated spots.

Identification C


The color of the test solution should be yellow and that of the blank should be red.

Specific Optical Rotation


+ 127.000 to +133.000

Related Substance  (By HPLC )


Any individual impurity: NMT 1.00%w/w.
Other impurity: NMT 0.50%w/w.
Total impurity : NMT 1.50%w/w

Loss on drying


Not more than 0.50%.



97.00 to 102.00%.

End of specification