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S-23 10mg/capsule, 60 caps

S-23 (Mastorin) is a propanamide-class non-steroidal selective androgen receptor modulator (SARM) with high-affinity androgen receptor (AR) binding characteristics.

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S-23 (Mastorin) is a propanamide-class non-steroidal selective androgen receptor modulator (SARM) with high-affinity androgen receptor (AR) binding characteristics. It functions as an AR agonist and has been extensively investigated in studies of receptor binding dynamics, ligand-receptor interactions, transcriptional regulation, and AR-mediated signaling mechanisms. Among non-steroidal SARMs, S-23 is recognized for its strong receptor affinity and well-characterized interaction profile, making it a valuable research tool for comparative androgen receptor pharmacology. Research applications include AR agonism studies, receptor selectivity investigation, androgen receptor signaling research, structure-activity relationship analysis, and mechanistic evaluation of non-steroidal androgen receptor modulators.

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3D Molecular Structure

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S235mg/100tabs | 10mg/60capsules
Chemical Formula C18H13ClF4N2O3
Synonyms Mastorin, (S)-N-(4-cyano-3-trifluoromethylphenyl)-3-(3-fluoro-4-chlorophenoxy)-2-hydroxy-2-methylpropanamide
Molar Mass 416.75 g/mol
CAS Number 1010396-29-8
PubChem CID 24892822
Total Compound Content 600 mg (10 mg per capsule)
Shelf Life 36 months
S-23 is a propanamide-class selective androgen receptor modulator (SARM) with among the highest documented androgen receptor (AR) binding affinities of any characterized non-steroidal SARM. Experimental investigations have examined its interactions with AR-mediated signaling pathways, receptor binding dynamics, transcriptional regulation mechanisms, and ligand-receptor interactions. In vitro studies have characterized its receptor activation profile across multiple experimental systems, making it a valuable research tool for comparative androgen receptor pharmacology. Its high receptor affinity and strong agonist activity have established S-23 as a useful reference compound in AR binding investigations, receptor occupancy studies, and mechanistic evaluations of non-steroidal androgen receptor modulators. Research applications include AR agonism pharmacology, receptor selectivity investigation, androgen receptor signaling research, and structure-activity relationship analysis. Supplied in 10 mg capsules. Independently third-party HPLC-tested; COA available per batch.

Results refer to the tested sample. Check the batch and date in the report.

HPLC S-23 (1881)
September 18, 2026
What distinguishes S-23 from other SARMs in androgen receptor research?

S-23 is characterized by exceptionally high androgen receptor (AR) binding affinity relative to many other non-steroidal SARMs. Its strong receptor interaction profile makes it a valuable research tool for studies examining ligand-receptor binding dynamics, receptor occupancy, transcriptional regulation, and AR-mediated signaling mechanisms.

These characteristics have established S-23 as a frequently utilized compound in comparative androgen receptor pharmacology investigations.

How does S-23 compare to other SARMs in receptor binding studies?

Experimental investigations have demonstrated that S-23 possesses a high-affinity interaction profile at the androgen receptor, making it useful for comparative studies involving receptor selectivity, ligand binding characteristics, and structure-activity relationships among non-steroidal androgen receptor modulators. Its well-characterized receptor pharmacology provides a valuable reference point for evaluating differences between SARM scaffolds and AR interaction patterns.

Why is S-23 used in androgen receptor pharmacology research?

S-23 is frequently utilized in studies of androgen receptor signaling due to its strong receptor affinity and well-characterized interaction profile.

Research applications include receptor binding investigations, AR-mediated transcriptional regulation studies, ligand-receptor interaction analysis, receptor occupancy experiments, and mechanistic evaluation of non-steroidal androgen receptor modulators. These properties make it a useful tool for examining fundamental aspects of androgen receptor pharmacology and signaling.

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