Description
S23 Powder — 2 Grams
S23, also designated S-23, is a non-steroidal selective androgen receptor modulator (SARM) of the aryl-propionamide class, developed in academic research at the University of Tennessee. This listing is a research-grade reference compound supplied in powder form for in vitro and laboratory investigation. Identity and purity are third-party verified and documented by a downloadable Certificate of Analysis.
- 99.8% purity (HPLC)
- Third-party verified
- 2,050 mg net
- Public COA
- UV-resistant foil pouch
Specifications & Documentation
- Compound
- S23 (S-23)
- IUPAC Name
- (2S)-3-(4-chloro-3-fluorophenoxy)-N-[4-cyano-3-(trifluoromethyl)phenyl]-2-hydroxy-2-methylpropanamide
- CAS Number
- 1010396-29-8
- Molecular Formula
- C₁₈H₁₃ClF₄N₂O₃
- Molar Mass
- 416.76 g/mol
- Compound Class
- Selective Androgen Receptor Modulator (SARM) · Aryl-propionamide
- WADA Classification
- Prohibited — Class S1.2 (Other Anabolic Agents)
- Form
- Crystalline powder
- Net Quantity
- 2,050 mg per pouch
- Verified Purity
- 99.8% by HPLC (current COA)
Third-Party Verification
Identity and purity are independently confirmed by MZ Biolabs (Tucson, AZ), a US DEA Schedule III licensed analytical facility (License RP0584676), using HPLC purity analysis and mass-spectrometry identity confirmation under Good Laboratory Practice (GLP) standards to support research reproducibility.
- Latest COA Date
- 10.17.2025
- Reported Purity
- 99.8%
- Methods
- HPLC–UV purity; MS identity confirmation
- Verifying Lab
- MZ Biolabs, Tucson, AZ (DEA Schedule III, RP0584676)
Current certificate of analysis for S23, issued by MZ Biolabs. Tap to view full size.
Open or download the current S23 COA · View the full COA archive →
Storage & Handling
Store in a cool, dry place away from direct sunlight to maximize shelf life. Supplied in a UV-resistant foil pouch to minimize photodegradation.
- Packaging
- UV-resistant sealed foil pouch
- Storage
- Cool, dry, dark; away from direct sunlight
- Handling
- Standard laboratory PPE and analytical-grade equipment
- Intended Use
- Laboratory and in vitro research only
Quality & Analytical Transparency
Independent analysis has repeatedly found that materials sold online as SARMs are frequently mislabeled or adulterated. A 2017 JAMA investigation that chemically analyzed products marketed as SARMs found that only a minority accurately matched their labeled contents, and a substantial share contained unapproved or entirely different substances.[5] Third-party testing is the control that distinguishes a documented reference compound from an unverified one.
Research Context
S23 was developed and characterized by the University of Tennessee research group responsible for several early aryl-propionamide SARMs.[4] Its preclinical characterization in rats evaluated high-affinity androgen receptor binding, tissue selectivity, and its potential as a component of hormonal male contraception, including the reversibility of its effects on spermatogenesis.[1] Later rat studies examined it in models of glucocorticoid- and hypogonadism-induced muscle atrophy[2] and of sexual motivation in ovariectomized female rats.[3] S23 has not been evaluated in published human clinical trials, and its safety profile in humans is unknown.
This material is supplied strictly as a reference compound to support such laboratory investigation. It is not a therapeutic product, dietary supplement, or sports supplement, and no clinical or performance outcomes are claimed or implied for any individual.
Compliance & Legal Status
S23 is an investigational compound that has not been approved by the U.S. Food and Drug Administration for human use. It is not a dietary supplement, and marketing it for human ingestion is unlawful. It is supplied exclusively for laboratory research purposes.
Scientific References
- Jones A, Chen J, Hwang DJ, Miller DD, Dalton JT. Preclinical characterization of a (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro, 4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide: a selective androgen receptor modulator for hormonal male contraception. Endocrinology. 2009;150(1):385–395.
- Jones A, Hwang DJ, Narayanan R, Miller DD, Dalton JT. Effects of a novel selective androgen receptor modulator on dexamethasone-induced and hypogonadism-induced muscle atrophy. Endocrinology. 2010;151(8):3706–3719.
- Jones A, Hwang DJ, Duke CB 3rd, et al. Nonsteroidal selective androgen receptor modulators enhance female sexual motivation. J Pharmacol Exp Ther. 2010;334(2):439–448.
- Narayanan R, Mohler ML, Bohl CE, Miller DD, Dalton JT. Selective androgen receptor modulators in preclinical and clinical development. Nucl Recept Signal. 2008;6:e010.
- Van Wagoner RM, Eichner A, Bhasin S, Deuster PA, Eichner D. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet. JAMA. 2017;318(20):2004–2010.
- World Anti-Doping Agency. The Prohibited List, Section S1.2: Other Anabolic Agents. WADA.org.
Research Disclaimer
For laboratory research use only. This preparation is not approved by the FDA for human use. S23 is not a dietary or sports supplement and is not intended for human or animal consumption.
All products on this website are intended exclusively for research and development purposes. The statements herein have not been evaluated by the U.S. Food and Drug Administration. Neither the statements nor the products are intended to diagnose, treat, cure, or prevent any disease. Sports Technology Labs are chemical suppliers, not medical practitioners; our expertise is sourcing and quality control.





