What Is Enclomiphene? Research Guide
Definition
Enclomiphene is the trans (E) isomer of clomiphene, a non-steroidal selective estrogen receptor modulator with molecular formula C26H28ClNO and a molecular weight of 405.96 Da (CAS 15690-57-0 for the free base). It is a triphenylethylene small molecule rather than a peptide, and it is studied in hypothalamic-pituitary-gonadal axis and estrogen receptor research.
Key Takeaways
- →Enclomiphene is the trans (E) isomer of clomiphene, a non-steroidal selective estrogen receptor modulator with molecular formula C26H28ClNO and a molecular weight of 405.96 Da (CAS 15690-57-0 for the free base). It is a triphenylethylene small molecule rather than a peptide, and it is studied in hypothalamic-pituitary-gonadal axis and estrogen receptor research..
- →Available for in-vitro research at ≥99% HPLC-verified purity from Peptide.Express.
- →Certificate of Analysis included with every order. Same-day US shipping.
Enclomiphene Specifications
| Property | Value |
|---|---|
| Compound | Enclomiphene |
| CAS Number | 15690-57-0 |
| Molecular Formula | C26H28ClNO |
| Molecular Weight | 405.96 Da |
| Mechanism Class | Selective estrogen receptor modulator (trans-isomer of clomiphene) |
| Purity | ≥99% by HPLC, batch-specific CoA included |
Registry records for Enclomiphene: PubChem
Enclomiphene Mechanism of Action
Clomiphene citrate is not one compound but a mixture of roughly 62 percent enclomiphene and 38 percent zuclomiphene, and the two isomers behave in opposite directions: zuclomiphene is the estrogenic isomer with a long elimination half-life, enclomiphene the antiestrogenic one. Enclomiphene antagonizes estrogen receptor alpha at the hypothalamus and pituitary, lifting the negative feedback estradiol exerts on GnRH pulse frequency, and published models report a resulting rise in LH and FSH. Isolating the trans isomer is the whole research rationale, since it separates that feedback-blocking activity from an estrogenic isomer that accumulates with repeated administration. Being a small molecule, it is orally active and needs none of the handling the peptides in this library require.
Enclomiphene Research Applications
Hypothalamic-pituitary-gonadal feedback models, where enclomiphene interrupts estradiol negative feedback without introducing an exogenous androgen.
Estrogen receptor subtype pharmacology, using competitive binding and reporter-gene assays at ER-alpha and ER-beta.
Isomer separation and purity analysis. Resolving enclomiphene from zuclomiphene by chiral or reversed-phase HPLC is both a routine analytical exercise and a genuine question about any supplied material.
Comparative SERM studies against tamoxifen and raloxifene, which share or contrast the triphenylethylene scaffold and differ in tissue selectivity.
Enclomiphene Storage Requirements
Enclomiphene is a small molecule, not a peptide, and it does not require the cold chain the rest of this library does. Store it dry, sealed and protected from light at controlled room temperature. The light requirement is the one that matters: triphenylethylenes photoisomerize, and light exposure can convert trans material toward the cis isomer, changing what is actually in the container rather than merely degrading it.
Enclomiphene at Peptide.Express
All Enclomiphene sold by Peptide.Express is HPLC-verified at ≥99% purity with a Certificate of Analysis included. Same-day US shipping on orders before 2 PM EST. For in-vitro laboratory research use only.
View Enclomiphene Product DetailsFrequently Asked Questions
What is Enclomiphene?
Enclomiphene is the trans (E) isomer of clomiphene, a non-steroidal selective estrogen receptor modulator. The free base has molecular formula C26H28ClNO, molecular weight 405.96 Da and CAS number 15690-57-0. It is studied in hypothalamic-pituitary-gonadal axis research and estrogen receptor pharmacology, for laboratory use only.
What is the difference between Enclomiphene and clomiphene?
Clomiphene citrate is a mixture of two geometric isomers, approximately 62 percent enclomiphene (trans) and 38 percent zuclomiphene (cis). Enclomiphene is the antiestrogenic isomer and clears comparatively quickly; zuclomiphene is estrogenic with a much longer half-life and accumulates on repeated administration. Isolating enclomiphene is an attempt to retain the first activity without the second.
Is Enclomiphene a peptide?
No. Enclomiphene is a triphenylethylene small molecule with a chlorine substituent and a tertiary amine side chain, structurally closer to tamoxifen than to anything else in this library. It contains no amino acids and no peptide bonds. It appears in this research library because it is studied in the same HPG-axis research area as several peptides here, not because it shares their chemistry.
What is the CAS number of Enclomiphene?
The free base is CAS 15690-57-0, formula C26H28ClNO, 405.96 Da. Note that 7599-79-3 is a separate registry entry for enclomiphene citrate (C32H36ClNO8), the citrate salt and a heavier molecule. Sources that use the two numbers interchangeably are describing different materials, and the distinction matters when weighing a stated purity or mass.
Is Enclomiphene FDA approved?
No. Enclomiphene citrate was developed as Androxal and was not approved by the FDA; there is no approved single-isomer enclomiphene product in the United States. Racemic clomiphene citrate is separately approved, but that is a different, two-isomer material. Peptide.Express supplies enclomiphene for research use only.
Where can I buy Enclomiphene for research?
Research-grade Enclomiphene is available from Peptide.Express at ≥99% HPLC-verified purity with a Certificate of Analysis included. Visit peptide.express/catalog/enclomiphene-oral-tablets for full specifications.
References
- Wiehle RD, Cunningham GR, Pitteloud N, Wike J, Hsu K, Fontenot GK, Rosner M, Dwyer A, Podolski J. Testosterone restoration by enclomiphene citrate in men with secondary hypogonadism: pharmacodynamics and pharmacokinetics. BJU Int. 2013. Read Wiehle et al.'s trial of enclomiphene citrate in secondary hypogonadism
- Mikkelson TJ, Kroboth PD, Cameron WJ, Dittert LW, Chungi V, Manberg PJ. Single-dose pharmacokinetics of clomiphene citrate in normal volunteers. Fertil Steril. 1986. Read Mikkelson et al.'s isomer-resolved clomiphene citrate pharmacokinetics
- Clomiphene citrate tablets, FDA-approved prescribing information via DailyMed. Racemic clomiphene citrate holds approval with its own labelling; enclomiphene as a single isomer does not. Read the clomiphene citrate FDA prescribing information
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