$603.00 - $603.00
Antide is a highly modified decapeptide antagonist of the GnRH receptor developed through extensive structure–activity optimization of the native GnRH scaffold.
Its sequence contains aromatic D-amino acids, nicotinoylated lysines and an isopropyl-substituted lysine, giving the molecule a chemical architecture markedly different from both native GnRH and simpler agonist analogs.
Product Information
| Property | Specification |
|---|---|
| Product Name | Antide Acetate |
| CAS No. | 112568-12-4 |
| Condensed Sequence | Ac-D-Nal(2)-D-Phe(4-Cl)-D-Pal(3)-Ser-Lys(Nic)-D-Lys(Nic)-Leu-Lys(iPr)-Pro-D-Ala-NH₂ |
| Peptide Length | 10 amino-acid residues |
| Peptide Formula | C82H108ClN17O14 |
| Peptide Moiety Molecular Weight | Approximately 1591.29 Da |
| N-Terminus | Acetylated |
| C-Terminus | D-Ala-NH₂ |
| Key Side-Chain Modifications | Lys(Nic)5, D-Lys(Nic)6, Lys(iPr)8 |
| Primary Target | GnRH receptor / GNRHR |
| Pharmacological Role | GnRH receptor antagonist |
Non-Natural Residues Define Antide
Antide contains three highly modified N-terminal residues: D-Nal(2), 4-chloro-D-Phe and D-Pal(3). These residues introduce large aromatic and heteroaromatic surfaces into the receptor-binding region of the peptide.
Positions 5 and 6 contain nicotinoylated lysine side chains, while position 8 contains an isopropyl-modified lysine. The result is a molecule whose receptor-recognition properties arise from both backbone stereochemistry and extensive side-chain engineering.
This makes Antide particularly useful for studying how non-proteinogenic amino acids can convert a natural agonist scaffold into a high-affinity antagonist.
Competitive GnRH Receptor Antagonism
Classical pituitary-cell experiments demonstrated that Antide inhibits GnRH-stimulated LH and FSH secretion without producing detectable agonist activity under the tested conditions.
The inhibition was reversible after peptide removal, and kinetic analysis supported direct competition with GnRH at the pituitary receptor.
We recommend using Antide as a defined receptor antagonist rather than describing its action as agonist-induced desensitization.
A Conformationally Organized Peptide Antagonist
Two-dimensional NMR studies found that Antide adopts a relatively organized delta-shaped conformation in aqueous solution. The structure includes a turn around the D-Pal3-Ser4 region and close spatial association between the aromatic D-Nal1 side chain and the modified Lys8 residue.
The conformational behavior changes in strongly organic solvent environments, demonstrating that solvent composition can influence the structural ensemble of this highly modified peptide.
This provides a useful experimental link between solution conformation and receptor-directed peptide design.
Antide and Cetrorelix Are Not Interchangeable Antagonists
| Feature | Antide | Cetrorelix |
|---|---|---|
| Length | 10 residues | 10 residues |
| Positions 5-6 | Lys(Nic), D-Lys(Nic) | Tyr, D-Cit |
| Position 8 | Lys(iPr) | Arg |
| Pharmacological Role | GnRHR antagonist | GnRHR antagonist |
| Distinct Research Theme | Conformation and side-chain engineering | Competitive blockade and receptor-state pharmacology |
The shared antagonist classification does not mean the two molecules interact with the receptor identically. Their side-chain chemistry and solution behavior are substantially different.
Researchers can compare Antide with Cetrorelix Acetate.
Solubility and Analytical Considerations
The multiple aromatic and chemically modified side chains of Antide make solution conditions an important experimental variable. Solvent composition, concentration and pH should be kept consistent when receptor or conformational studies are compared.
The reported formula and molecular weight above describe the Antide peptide entity associated with CAS 112568-12-4. If the supplied material contains acetate counterion, exact counterion stoichiometry should be confirmed from lot-specific analytical information before calculating total salt molecular weight.
Frequently Asked Questions
Is Antide a GnRH agonist?
No. Antide is a peptide GnRH receptor antagonist and has been shown to competitively inhibit GnRH-stimulated gonadotropin responses.
What makes Antide structurally unusual?
It contains multiple D-amino acids, aromatic non-natural residues, nicotinoylated lysines and an isopropyl-modified lysine.
Does Antide have a defined solution conformation?
NMR studies have identified a relatively stable delta-shaped conformational ensemble in aqueous solution, although the structure changes with solvent environment.
Can Antide-related antagonist libraries be synthesized?
Non-natural amino-acid substitutions and focused GnRH antagonist libraries can be evaluated through Chemical Peptide Synthesis.