Professional Product Parameters: CAS 851199-59-2 (Linaclotide )

1. Basic Identification

• CAS No.：851199-59-2 (free peptide); acetate salt is commonly used in formulations
• Product Name：Linaclotide ; Acetate Linaclotide
• IUPAC Name：L-Tyrosine, L-cysteinyl-L-cysteinyl-L-α-glutamyl-L-tyrosyl-L-cysteinyl-L-cysteinyl-L-asparaginyl-L-prolyl-L-alanyl-L-cysteinyl-L-threonylglycyl-L-cysteinyl-, cyclic (1→6),(2→10),(5→13)-tris(disulfide)
• Peptide Sequence：H-Cys1-Cys2-Glu3-Tyr?-Cys?-Cys?-Asn?-Pro?-Ala?-Cys1?-Thr11-Gly12-Cys13-Tyr1?-OH (disulfide bonds: Cys1?Cys?, Cys2?Cys1?, Cys??Cys13)
• Synonyms：Linaclotide acetate; Linaclotidum; Linares; Zelnorm (brand name)
• MDL：MFCD16217356
• InChIKey：KXGCNMMJRFDFNR-VRMHCMCOSA-N
• SMILES：CC1C(=O)NC2CSSCC3C(=O)NC(C(=O)NC(C(=O)NC(CSSCC(NC(=O)CNC(=O)C(NC2=O)C(C)O)C(=O)NC(CC4=CC=C(C=C4)O)C(=O)O)C(=O)NC(CSSCC(C(=O)N3)N)C(=O)NC(C(=O)N5CCCC5C(=O)N1)CC(=O)N)CC6=CC=C(C=C6)O)CCC(=O)OMOLNOVA

2. Chemical Data

• Molecular Formula：C??H??N??O??S?
• Molecular Weight：1526.74 g/mol (exact mass: 1525.39 Da)
• Elemental Analysis：C 46.40%, H 5.21%, N 13.76%, O 22.01%, S 12.62%
• Density：1.60 g/cm3 (predicted)
• pKa：3.05 ± 0.10 (predicted)
• LogP：-2.89 (calculated)
• TPSA：627.50 ?2
• H?Bond Donors：21; H?Bond Acceptors：36
• Rotatable Bonds：42

3. Physical & Chemical Properties

• Appearance：White to off?white amorphous powder (acetate salt)
• Solubility：
  • Water：~20 mg/mL (13.10 mM, soluble with heating)
  • DMSO：~50 mg/mL (32.75 mM, soluble with heating)
  • Methanol：slightly soluble (heated); insoluble in hexane, ether
• Melting Point：231–235 °C (decomposition)
• Boiling Point：2045.0 ± 65.0 °C (predicted)
• pH (1% aq. acetate)：4.5–6.5
• Stability：Hygroscopic; sensitive to light, heat, and oxidation; aqueous solutions unstable, prepare fresh
• Storage：-20 °C (long?term); 2–8 °C (short?term); sealed, dry, light?proof, inert gas protection

4. Product Specifications (Typical)

• Purity：≥98.0% (HPLC); ≥99.0% (API grade)
• Single Impurity：≤1.0%
• Peptide Content：≥80.0%
• Acetate Content：5.0%–12.0%
• Moisture：≤10.0%
• Heavy Metals：≤10 ppm; Pb ≤0.5 ppm, Cd ≤2.5 ppm, Hg ≤1.5 ppm, As ≤0.15 ppm
• Residue on Ignition：≤1.0%
• Grade：Research grade / Pharmaceutical API grade
• Packing：1 mg, 5 mg, 10 mg, 25 mg, 100 mg, 1 g (lyophilized, aluminum foil bag); bulk packaging

5. Biological Function & Applications

• Mechanism：Potent, selective agonist of guanylate cyclase?C (GC?C) in intestinal epithelium; increases cGMP, promotes chloride/bicarbonate secretion, softens stool, and reduces visceral hypersensitivity
• Core Activity：
  • FDA?approved for irritable bowel syndrome with constipation (IBS?C) and chronic idiopathic constipation (CIC)
  • Enhances intestinal fluid secretion and motility; reduces abdominal pain
• Applications
  • Pharmaceutical API 
  • Research tool for gastrointestnal physiology, GC?C signaling, and visceral pain
  • Intermediate for peptide drug development

6. Safety & Handling

• GHS Classification：Acute Tox. 4 (oral); not a hazardous substance for skin/eye contact
• Handling：Avoid inhalation; use in fume hood; wear PPE (gloves, goggles)
• Disposal：Dispose per local chemical waste regulations
• Note：For research and pharmaceutical use only; unauthorized human administration is prohibited