L-Homocystine

About L-Homocystine

L-Homocystine is a high-purity reference standard of Cystine carrying the CAS registry number 626-72-2. Formula C8H16N2O4S2, molecular weight 268.4 g/mol. Systematically, it is named (2S)-2-amino-4-[[(3S)-3-amino-3-carboxypropyl]disulfanyl]butanoic acid. Alternative names: Homocystine, L- and (H-HoCys-OH)2.

It is supplied as a solid. Store the standard in its sealed vial, protected from light and moisture, and follow the storage condition printed on the COA. Handle it with standard laboratory precautions and appropriate personal protective equipment.

Laboratories use this Cystine standard for identity and assay testing, system suitability checks and method validation supporting ANDA and DMF filings. It is used across pharmaceutical manufacturing and academic and industrial research.

Standard pack sizes are 10 mg, 25 mg, 50 mg and 100 mg, and every batch ships with a Certificate of Analysis (COA) and we export worldwide.

Typical applications

Identification & assay
Method development & validation
QC reference material

Industries

Related to Cystine

View every impurity, metabolite and intermediate we list for Cystine.

Cystine impurities

Specifications & identifiers

Chemical identifiers
Product name	L-Homocystine
Catalogue No.	VQ-036488
CAS Number	626-72-2
IUPAC name	(2S)-2-amino-4-[[(3S)-3-amino-3-carboxypropyl]disulfanyl]butanoic acid
Molecular formula	C₈H₁₆N₂O₄S₂
Molecular weight	268.4 g/mol
Exact mass	268.0551
Grade	Reference Standard
HSN code	38229090
InChIKey	ZTVZLYBCZNMWCF-WDSKDSINSA-N
SMILES	C(CSSCC[C@@H](C(=O)O)N)[C@@H](C(=O)O)N
PubChem CID	439579

Physical properties
Physical form	Solid
LogP (XLogP3)	-5.6
H-bond donors / acceptors	4 / 8
TPSA	177 Å²
Synonyms	Homocystine, L-, 2-amino-4-{[(3S)-3-amino-3-carboxypropyl]disulfanyl}butanoic acid, [S-(R,R)]-4,4'-dithiobis[2-aminobutyric] acid, (S-(R,R))-4,4'-Dithiobis(2-aminobutyric) acid, 2-amino-4-(((3S)-3-amino-3-carboxypropyl)disulfanyl)butanoic acid, (H-HoCys-OH)2, (2S,2'S)-4,4'-Disulfanediylbis(2-aminobutanoic acid), L-4,4'-Dithiobis(2-aminobutanoic acid), (2S)-2-amino-4-{[(3S)-3-amino-3-carboxypropyl]disulfanyl}butanoic acid

Documents

Safety Data Sheet (SDS)16-section GHS · on request Certificate of AnalysisTypical / batch COA · on request Specification sheetTDS / MOA · on request

Frequently asked questions

What is the CAS number of L-Homocystine?

The CAS Registry Number of L-Homocystine is 626-72-2. It is also known as Homocystine, L-, 2-amino-4-{[(3S)-3-amino-3-carboxypropyl]disulfanyl}butanoic acid, [S-(R*,R*)]-4,4'-dithiobis[2-aminobutyric] acid.

What is the molecular formula and molecular weight of L-Homocystine?

L-Homocystine has the molecular formula C8H16N2O4S2 and a molecular weight of 268.4 g/mol. Its IUPAC name is (2S)-2-amino-4-[[(3S)-3-amino-3-carboxypropyl]disulfanyl]butanoic acid.

What is L-Homocystine used for?

L-Homocystine is supplied as a characterised reference material related to Cystine. It is used for analytical method development and validation (AMV), impurity profiling, stability studies and quality control, and in ANDA/DMF regulatory filings.

Which grade and pack sizes of L-Homocystine can I order?

We supply L-Homocystine in Reference Standard grade, in 10 mg, 25 mg, 50 mg, 100 mg packs. Larger bulk quantities and custom packing are quoted on request.

Do you provide a COA and SDS with L-Homocystine?

Yes. Every lot of L-Homocystine is shipped with a batch-specific Certificate of Analysis, and a 16-section GHS Safety Data Sheet is provided with the quotation and the shipment.

Can L-Homocystine be shipped internationally?

Yes. We export L-Homocystine worldwide by air and sea freight or express courier, on EXW, FOB, CIF, CFR or DAP Incoterms, with full export documentation.