(6S,7S,8R,10R,13S,14S,17R)-6-hydroxy-10,13-dimethyl-7-methylsulfanylspiro[2,6,7,8,9,11,12,14,15,16-decahydro-1H-cyclopenta[a]phenanthrene-17,5'-oxolane]-2',3-dione, commonly known as 6β-Hydroxy-7α-(thiomethyl)spironolactone or Canrenone acid, is a major active metabolite of the steroidal drug spironolactone. It is a key intermediate in the metabolic pathway of spironolactone, a potassium-sparing diuretic and aldosterone antagonist used to treat conditions like hypertension, heart failure, and hyperaldosteronism. As a metabolite, this compound itself possesses pharmacological activity, contributing to the overall therapeutic effects of spironolactone. Its primary role in the pharmaceutical industry is as a reference standard for analytical purposes. It is crucial for pharmacokinetic studies, bioanalytical method development, and quality control to monitor the metabolism and impurity profile of spironolactone drug products. Due to its significance in drug metabolism and regulatory compliance, this compound is primarily supplied as a high-purity analytical standard. It is essential for ensuring the safety, efficacy, and consistency of spironolactone-based medications through precise quantification and identification in biological matrices and pharmaceutical formulations.