Description

Cysteine, Propyl Ester (9Ci) is a protected derivative of the amino acid cysteine, where the thiol group is esterified with propanol. This modification enhances its stability and alters its solubility profile, making it a valuable intermediate in organic synthesis and peptide chemistry. It is primarily utilized by research institutions and industrial manufacturers in the pharmaceutical, biotechnology, and fine chemical sectors for applications requiring controlled thiol reactivity.

Application

• Pharmaceutical Intermediate: A key building block in the synthesis of peptide-based drugs and prodrugs, where the protected thiol group is crucial for specific coupling reactions.
• Bioconjugation Reagent: Used in the modification of proteins, antibodies, and other biomolecules to introduce functional handles or alter physicochemical properties.
• Chemical Synthesis: Serves as a chiral synthon in asymmetric synthesis for creating complex molecules with sulfur-containing functional groups.
• Research & Development: Employed in academic and industrial R&D for studying enzyme mechanisms, redox biology, and as a standard in analytical method development.
• Cosmetic Ingredient Precursor: Acts as a precursor for compounds used in hair care and skincare formulations that benefit from controlled sulfur chemistry.

Basic Information

Product Name	Cysteine, Propyl Ester (9Ci)
CAS No.	125511-28-6
Molecular Formula	C6H13NO2S
Molecular Weight	163.24 g/mol
Synonyms	L-Cysteine propyl ester; S-Propyl L-cysteine; Propyl L-cysteinate; 2-Amino-3-(propylthio)propanoic acid; Cysteine S-propyl ester; (R)-2-Amino-3-(propylthio)propanoic acid; NSC 403819; Cysteine propyl ester hydrochloride (salt form)
EINECS	Contact for details

Quality Control

Our Cysteine, Propyl Ester (9Ci) is manufactured under strict quality management systems. Each batch undergoes comprehensive analytical testing to ensure identity, purity, and consistency. Certificates of Analysis (COA) detailing specifications such as assay, chiral purity, and impurity profiles are provided with every shipment. We can support development and production needs compliant with cGMP and ICH guidelines.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated place at controlled room temperature (15-25°C). This compound is hygroscopic (moisture-sensitive); keep the container tightly sealed to minimize exposure to atmospheric humidity.

Specification

Item	Specification
Appearance	White to off-white powder or crystalline solid
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Chiral Purity (HPLC)	≥ 99.0% (L-isomer)
Water Content (KF)	≤ 1.0%
Residue on Ignition	≤ 0.1%
Heavy Metals	≤ 10 ppm

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