Clobetasol Propionate EP Impurity A

JR-ST1011-01

Variant ofClobetasol Propionate EP/BP CRS

Betamethasone 17-propionate (9-fluoro-11β,21-dihydroxy-16β-methyl-3,20-dioxopregna-1,4-dien-17-yl propanoate); 21-hydroxy precursor and hydrolysis impurity of clobetasol propionate (EP Impurity A).

Structure & identifiers

2D structure — select to enlarge

Catalogue code

JR-ST1011-01

Category

Corticosteroids

CAS number

5534-13-4

Grade

Impurity reference standard

Pharmacopoeia

Ph. Eur.

Molecular formula

C25H33FO6

Molecular weight

448.53 g/mol

Pack sizes

25 mg · 50 mg · 100 mg · 500 mg

Record updated

12 Nov 2026

Chemical name

Clobetasol Propionate EP Impurity A

SMILES

CCC(=O)O[C@]1(C(=O)CO)[C@@H](C)C[C@H]2[C@@H]3CCC4=CC(=O)C=C[C@]4(C)[C@@]3(F)[C@@H](O)C[C@]12C