Description

Thiopeptin B is a naturally occurring thiazole-containing cyclic peptide antibiotic isolated from Streptomyces laurentii, recognized for its potent activity against Gram-positive bacteria and mycoplasmas. It serves as a critical research tool in microbiology, antibiotic resistance studies, and mechanistic investigations of ribosomal inhibition. Pharmaceutical R&D laboratories, contract research organizations (CROs), and academic institutions engaged in antimicrobial discovery and mode-of-action profiling rely on high-purity Thiopeptin B CAS NO 37339-66-5 for reproducible, publication-grade results.

Application

• Antibiotic mechanism-of-action studies targeting the 50S ribosomal subunit
• In vitro screening of bacterial strains for intrinsic and acquired resistance to thiopeptide antibiotics
• Reference standard in HPLC and LC-MS/MS quantification methods for antibiotic residue analysis
• Tool compound in structural biology (e.g., cryo-EM and X-ray crystallography) to probe ribosome–ligand interactions
• Development and validation of microbial growth inhibition assays (e.g., agar diffusion, broth microdilution)
• Quality control reference material for biosynthetic pathway engineering of thiopeptide-producing actinomycetes
• Comparative pharmacological evaluation in preclinical models of mycoplasma infection
• Stability-indicating method development for peptide-based therapeutics under stress conditions

Basic Information

Product Name	Thiopeptin B
CAS No.	37339-66-5
Molecular Formula	C54H61N13O13S6
Molecular Weight	1324.48 g/mol
Synonyms	Thiopeptin B; Thiostrepton B; TP-B; NSC 121349; Antibiotic 1325-A; 1325-A; Streptothricin B (historical misnomer); Cyclo-(N-Me-D-Phe–D-Ala–D-Ser–D-Val–D-Orn–D-Abu–D-Val–D-Orn–D-Abu–D-Val–D-Orn–D-Abu–D-Val–D-Orn–D-Abu); Thiazolyl peptide B
EINECS	Not listed (no EINECS assigned)

Quality Control

Our products undergo rigorous quality testing to ensure compliance with industry standards. Certificates of Analysis (COA) are available upon request. Each batch of Thiopeptin B is verified for identity (IR, HPLC retention time, MS), assay (HPLC), and purity (≥95.0% by area normalization). Testing adheres to principles aligned with USP General Chapters <1058> Analytical Instrument Qualification and <1225> Validation of Compendial Procedures, supporting regulatory submissions and GLP-compliant research.

Storage

Preserve in a tightly closed container, protected from light. Store at 2–8 °C under inert atmosphere (argon or nitrogen) to prevent oxidation and moisture uptake. Due to its hygroscopic nature, maintain low-humidity conditions (<30% RH) and minimize exposure to ambient air during handling.

Specification

Item	Specification
Appearance	Off-white to pale yellow amorphous powder
Identification (IR)	Conforms to reference spectrum (KBr pellet)
Identification (HPLC)	Retention time matches reference standard (±0.2 min)
Assay (HPLC)	95.0–102.0% (area %, external standard)
Related Substances (HPLC)	Single impurity ≤1.0%; Total impurities ≤3.0%
Residue on Ignition	≤0.5%
Water (KF)	≤5.0%
Solubility	Soluble in DMSO, methanol, and chloroform; sparingly soluble in water

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.