Antide Acetate | CAS 112568-12-4 / 625092-10-6 | GnRH Receptor Antagonist (Research Use Only) | Knowlux
Product Description
Antide Acetate, CAS 112568-12-4 (free peptide) / 625092-10-6 (acetate salt), is a synthetic decapeptide gonadotropin-releasing hormone (GnRH) receptor antagonist supplied by Knowlux for laboratory research use. The sequence is Ac-D-2-Nal-D-Phe(4-Cl)-D-3-Pal-Ser-Lys(nicotinoyl)-D-Lys(nicotinoyl)-Leu-Lys(isopropyl)-Pro-D-Ala-NH2. The free peptide molecular formula is C82H108ClN17O14 and the molecular weight is 1591.29 to 1591.32 g/mol depending on calculation convention; the acetate salt corresponds to C84H112ClN17O16 with a molecular weight of 1651.34 g/mol. Each lot is released with a lot-specific COA, MSDS and analytical traceability.
CAS and Salt Form Clarification: CAS 112568-12-4 is the free peptide registry, and it is the identifier most consistently paired with the formula C82H108ClN17O14 and MW 1591.29 to 1591.32 across GL Biochem, SBS Genetech, TargetMol, MedChemExpress, Selleck, and ChemicalBook. The product name Antide Acetate is frequently applied to the CAS 112568-12-4 material in commercial listings, creating a discrepancy between the declared name and the declared formula. A separate acetate-salt registry, CAS 625092-10-6, corresponds to the formula C84H112ClN17O16 and MW 1651.34, as confirmed by TargetMol, Adooq, CymitQuimica, BenchChem, and MedChemExpress. The molecular weight difference between the free peptide and the monoacetate is 60 g/mol (1591.34 versus 1651.34), which is material for molarity calculations. Knowlux specifies the salt basis, acetate content, and water content per lot on the COA. Buyers should confirm whether the quoted material is free peptide or acetate salt before procurement, and should verify that the molecular weight on the COA reconciles to the declared salt form rather than relying on the product name alone.
Structural Note: Antide is a third-generation GnRH antagonist distinguished from earlier antagonists such as Cetrorelix by the incorporation of nicotinoyl groups on both lysine residues at positions 6 and 7 (Lys(Nic) and D-Lys(Nic)), in addition to the D-2-Nal, D-Phe(4-Cl), and D-3-Pal substitutions at positions 1 to 3. The peptide is linear, contains no cysteine or disulfide bonds, and has an acetylated N-terminus and a D-alaninamide C-terminus. Unlike the disulfide-constrained peptides in the Linaclotide and Plecanatide families, Antide is not sensitive to reducing agents. The multiple aromatic and chemically modified side chains (naphthylalanine, chlorophenylalanine, pyridylalanine, nicotinoyl-lysine) make solution conditions an experimental variable; solvent composition, concentration, and pH should be kept consistent when receptor or conformational studies are compared.
Product Parameters
| Item | Specification |
|---|---|
| Product Name | Antide Acetate |
| Synonyms | Iturelix; D-21074; ORF 23541; Ac-D-2-Nal-D-Phe(4-Cl)-D-3-Pal-Ser-Lys(Nic)-D-Lys(Nic)-Leu-Lys(iPr)-Pro-D-Ala-NH2 |
| CAS No. | 112568-12-4 (free peptide); 625092-10-6 (acetate salt) |
| Molecular Formula | C82H108ClN17O14 (free peptide); C84H112ClN17O16 (acetate salt) |
| Molecular Weight | 1591.29 to 1591.32 g/mol (free peptide); 1651.34 g/mol (acetate salt) |
| Sequence (3-letter) | Ac-D-2-Nal-D-Phe(4-Cl)-D-3-Pal-Ser-Lys(nicotinoyl)-D-Lys(nicotinoyl)-Leu-Lys(isopropyl)-Pro-D-Ala-NH2 |
| Sequence Length | 10 residues, linear |
| Key Structural Features | Acetylated N-terminus; D-2-Nal1; D-Phe(4-Cl)2; D-3-Pal3; Lys(Nic)6; D-Lys(Nic)7; Lys(iPr)8; D-Ala-NH2 C-terminus; no cysteine or disulfide |
| Appearance | White to off-white powder |
| Solubility | DMSO 100 mg/mL (62.84 mM); water 50 mg/mL (31.42 mM); ethanol 33 mg/mL (20.73 mM); water 10 mg/mL (6.28 mM) per Biorbyt lot (see Solubility section) |
| Purity | >=95.0% to >=99.53% (HPLC; supplier-dependent) |
| Identity | Confirmed by LC-MS and HPLC |
| Grade | Research grade |
| Counter-ion | Free peptide or acetate (lot-specific, declared on COA) |
| Acetate Content | <=12.0% (HPIC) |
| Peptide Content | >=80.0% (by %N) |
| Water Content | <=8.0% (Karl Fischer) |
| Single Impurity | <=1.0% (HPLC) |
| Mass Balance | 95.0% to 105.0% |
| Storage | See Storage and Stability section |
| Packaging | 1 mg / 5 mg / 10 mg / 25 mg / 50 mg / 100 mg vial; bulk on request |
| Application | Laboratory research use only |
| Origin | China |
Product Details
1. Overview
Antide (Iturelix) is a synthetic decapeptide that functions as a potent and selective competitive antagonist at the pituitary GnRH receptor. It belongs to the third-generation GnRH antagonist series and is structurally distinguished from Cetrorelix and Degarelix by the presence of nicotinoyl-modified lysine residues at positions 6 and 7. Antide binds the GnRH receptor without activating it, blocking GnRH-stimulated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release, and suppressing downstream gonadal steroidogenesis. In preclinical research, Antide has been used to study reproductive endocrinology, GnRH receptor pharmacology, and ovarian function; Selleck describes its activity in inhibiting apoptosis of preovulatory follicle cells in the rat ovary. The material supplied under this specification is research-grade and is not intended for human administration.
2. Receptor Pharmacology and Binding Affinity
Antide is a high-affinity GnRH receptor antagonist, and the published constants establish it as one of the more potent peptidic antagonists in the series. BenchChem compiles a dissociation constant (Kd) of 0.36 x 10^-9 M (+/- 0.13) at the human GnRH receptor, alongside comparative values of 0.19 x 10^-9 M for Cetrorelix and 0.30 x 10^-9 M for the agonist Buserelin. The same compilation reports an in vitro IC50 of approximately 1 x 10^-7 M for inhibition of GnRH-stimulated LH release from dispersed rat pituitary cells under simultaneous incubation, and approximately 1 x 10^-10 M under 48-hour pre-incubation conditions. The 1000-fold increase in potency with pre-incubation is a distinctive pharmacological feature of Antide and indicates a strong and stable receptor interaction that is not fully captured by simultaneous-incubation assays. A FEBs Letters comparative study reports a Kd of 0.36 +/- 0.13 nM for Antide, consistent with the BenchChem value. An additional high-affinity constant (0.67 +/- 0.09) appears in a patent table alongside values for related antagonists, but the receptor and assay context for that entry are not fully specified in the snippet and it is not adopted here as a primary constant. The antide-receptor interaction has also been characterized using a radioiodinated Antide analog, yielding an affinity constant in the range of 10^10 M^-1. These values are assay- and system-dependent and are provided for scientific reference only.
3. Research Applications
Published pharmacological characterizations describe the following research applications:
-
GnRH receptor binding and functional antagonist assays (radioligand displacement, LH/FSH suppression in pituitary cell models)
-
Comparative pharmacology of third-generation GnRH antagonists (Antide versus Cetrorelix, Degarelix, and Abarelix)
-
Reproductive endocrinology and ovarian follicle biology research models (inhibition of preovulatory follicle cell apoptosis)
-
Prostate cancer and hormone-dependent tumor research contexts
-
Structure-activity relationship studies of nicotinoyl-lysine substitutions in the antagonist series
-
Reference standard development for HPLC and LC-MS analytical methods
These descriptions are derived from published research and are provided for scientific reference only.
Quality Control
| Test Item | Method | Acceptance Criteria |
|---|---|---|
| Purity | RP-HPLC | >=95.0% (entry grade); >=97.0% (standard grade); >=98.0% (reference grade); 99.46% (Selleck batch); 99.53% (MedChemExpress LCMS); 99.57% (TargetMol batch) |
| Identity | LC-MS | Consistent with structure |
| Single Impurity | RP-HPLC | <=1.0% (reference grade) |
| Peptide Content | Nitrogen analysis (%N) | >=80.0% (reference grade) |
| Acetate Content | HPIC | <=12.0% (reference grade) |
| Water Content | Karl Fischer | <=8.0% (reference grade) |
| Mass Balance | Calculation | 95.0% to 105.0% (reference grade) |
| Endotoxin | LAL or chromogenic | <=50 EU/mg (reference grade) |
| Appearance | Visual | White to off-white powder |
Solubility and Handling
Solubility: Antide solubility data across suppliers are more consistent than for most peptides in this catalogue, with one notable outlier. Selleck batch-tested experimental data report DMSO 100 mg/mL (62.84 mM), water 50 mg/mL (31.42 mM), and ethanol 33 mg/mL (20.73 mM) at 25C. TargetMol and Selleck regional sites corroborate these values. Biorbyt reports a lower water solubility of 10 mg/mL (6.28 mM) with ultrasonic assistance, and LKT Labs states simply that the material is soluble in water without a numeric limit. The 50 mg/mL and 10 mg/mL aqueous figures differ by a factor of five and likely reflect differences in lot history, sonication technique, and whether the measurement was performed on a saturated solution. Selleck recommends a 10 mM DMSO stock as a working concentration and explicitly warns that moisture-contaminated DMSO reduces solubility and that fresh anhydrous DMSO should be used. For in vivo formulation, TargetMol describes a vehicle of 10% DMSO -> 40% PEG300 -> 5% Tween-80 -> 45% saline/PBS/ddH2O achieving 2 mg/mL, and Selleck lists a CMC-Na homogeneous suspension at >=5 mg/mL. For practical stock preparation, DMSO at 100 mg/mL is the most consistently supported condition; aqueous stock solutions should be prepared fresh and not stored for extended periods. Prepare solutions fresh and aliquot to avoid repeated freeze-thaw cycles.
Handling Precautions: Use powder-handling containment (glove box or fume hood with particulate control). Avoid inhalation of fine powder. Wear nitrile gloves, lab coat, and eye protection. Antide contains no cysteine or methionine, so reducing agents and methionine-oxidation protection measures are not required. The principal handling consideration is the hygroscopic nature of the lyophilized powder; equilibrate vials to room temperature before opening.
Storage and Stability
| Format | Temperature | Shelf Life |
|---|---|---|
| Lyophilized Powder | -20C, sealed, desiccated, protected from light | 3 years (Selleck, TargetMol, Adooq); >=2 years (Biorbyt) |
| Lyophilized Powder | -80C, sealed, desiccated | 2 years (MedChemExpress) |
| Lyophilized Powder | -20C, sealed, desiccated | 1 year (MedChemExpress); 3 years (Selleck) |
| Reconstituted Solution | -80C, aliquoted, sealed | 1 year (TargetMol, Selleck); 6 months (MedChemExpress) |
| Reconstituted Solution | -20C, aliquoted, sealed | 1 month (MedChemExpress, Selleck) |
Documentation Support
Per lot: COA, MSDS, HPLC chromatogram, and mass spectrometry data. Salt-form identity, acetate content, water content, and peptide content available on request. Custom specifications and third-party inspection can be arranged on a project basis.
About Knowlux
Knowlux Biotechnology is a GMP-oriented manufacturer and supplier of peptides, APIs and fine-chemical research compounds, operating from Hubei, China. We serve research groups, CDMOs and distributors in more than 40 countries, and support contract synthesis, custom packaging and technical documentation requests.
Compliance Statement
FOR RESEARCH USE ONLY. NOT FOR HUMAN USE. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE.
This product is supplied for laboratory research use only. It is not for human or animal administration, not for diagnostic or therapeutic use, not for retail sale, and not for personal use. Antide Acetate is not approved as a medicinal product in any jurisdiction. The purchaser is responsible for verifying product specifications against their specific research requirements and for compliance with all applicable institutional, local, and national regulations governing research chemical acquisition, storage, and use. Research context statements are for scientific reference only and do not constitute medical advice, promotional claims, or dosing guidance.
Data Verification Notes
The free peptide formula C82H108ClN17O14 and MW 1591.29 to 1591.32 are confirmed by GL Biochem, SBS Genetech, TargetMol, MedChemExpress, Selleck, and ChemicalBook. The acetate salt CAS 625092-10-6, formula C84H112ClN17O16, and MW 1651.34 are confirmed by TargetMol, Adooq, CymitQuimica, BenchChem, and MedChemExpress. The sequence Ac-D-2-Nal-D-Phe(4-Cl)-D-3-Pal-Ser-Lys(nicotinoyl)-D-Lys(nicotinoyl)-Leu-Lys(isopropyl)-Pro-D-Ala-NH2 is confirmed across GL Biochem, SBS Genetech, TargetMol, and Biozol. The Kd of 0.36 x 10^-9 M is from BenchChem and the FEBs Letters study; the IC50 values (approximately 1 x 10^-7 M and approximately 1 x 10^-10 M, simultaneous and 48-h pre-incubation, respectively) are from BenchChem. The 0.67 +/- 0.09 value in the patent table is noted for completeness but not adopted as a primary constant because the receptor and assay context are incomplete in the source. Solubility values are reported with their source conditions rather than reconciled into a single figure because the water data span 10 to 50 mg/mL and reflect different lots and dissolution techniques. Storage shelf-life divergence (-20C versus -80C for powder; 6 months versus 1 year for solutions at -80C) is reported as-is; the -20C powder condition is the most widely supported archival temperature.
Formatting Note: All formulas, sequences, and comparison operators use plain ASCII notation to prevent character corruption on the platform. Section headings, table alignment, and spacing follow the approved product detail pattern. No trailing spaces or non-breaking characters are used; tables use consistent pipe alignment.
