Estradiol Impurity 43 CAS 19590-55-7

Purity 97%+In StockPharmacopoeial Impurity Standards
CAS No.19590-55-7
Molecular FormulaC18H22Br2O2
Molecular Weight430.17 g/mol
CategoryPharmacopoeial Impurity Standards / EP Impurities
AvailabilityIn Stock

Chemical Structure

Estradiol Impurity 43 CAS 19590-55-7 chemical structure

Description

Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including Estradiol Impurity 43.

CATO supplies Estradiol Impurity 43 (CAS 19590-55-7), a pharmacopoeial impurity reference standard (molecular formula C18H22Br2O2, MW 430.17 g/mol) used for the identification and quantification of trace impurities in APIs.

Owing to a steroid core, a hydroxyl group, an ether linkage, bromine substitution, Estradiol Impurity 43 is typically off-white to pale yellow crystalline powder. Its solid-state physicochemical attributes — including a molecular weight of 430.17 g/mol — guide the selection of appropriate sample preparation and analytical techniques. The presence of an aromatic ring or conjugated system gives the compound characteristic absorption bands in the UV-Vis region, making it well suited to UV or diode-array detection (DAD).

This reference standard supports related-substances testing and method development in line with ICH Q3A/Q3B guidance on impurity control, and is suitable for system suitability testing and forced-degradation studies.

As a certified reference material (CRM), Estradiol Impurity 43 meets the metrological traceability requirements of ISO/IEC 17025 laboratories. Batch-to-batch consistency is monitored via control charts to guarantee comparable assigned values across lots.

Physical & Chemical Properties

Molecular FormulaC18H22Br2O2
Molecular Weight430.17 g/mol
AppearanceOff-white to pale yellow crystalline powder. (slight halide-like odor, low volatility)
Purity97%+
StorageStore at room temperature, protect from light
Solubility (reference)Soluble in chloroform, dichloromethane, ethyl acetate, DMSO
StabilityMay oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Contains ester bond; hydrolyzes under strong alkaline conditions
Degree of Unsaturation (DBE)7.0
UV AbsorptionUV-absorbing
Structural FeaturesAromatic ring present
CAS Registry Year (est.)1962
Halogen ContentBr-containing

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