B 581

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    WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 584109

CAS#: 149759-96-6

Description: B 581 is an inhibitor that specifically blocks farnesylated, but not geranylgeranylated or myristylated, oncogenic ras signaling and transformation.

Price and Availability

Size Price Shipping out time Quantity
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Pricing updated 2020-05-29. Prices are subject to change without notice.

B 581 is not in stock, may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to sales@medkoo.com to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 584109
Name: B 581
CAS#: 149759-96-6
Chemical Formula: C22H38N4O3S2
Exact Mass: 470.2385
Molecular Weight: 470.69
Elemental Analysis: C, 56.14; H, 8.14; N, 11.90; O, 10.20; S, 13.62

Synonym: B 581, B-581, B581

IUPAC/Chemical Name: L-Methionine, N-(N-(2-((2-amino-3-mercaptopropyl)amino)-3-methylbutyl)-L-phenylalanyl)-, (S-(R*,S*))-


InChi Code: InChI=1S/C22H38N4O3S2/c1-15(2)20(24-12-17(23)14-30)13-25-19(11-16-7-5-4-6-8-16)21(27)26-18(22(28)29)9-10-31-3/h4-8,15,17-20,24-25,30H,9-14,23H2,1-3H3,(H,26,27)(H,28,29)/t17-,18+,19+,20-/m1/s1

SMILES Code: CSCC[C@@H](C(O)=O)NC([C@H](CC1=CC=CC=C1)NC[C@@H](NC[C@@H](N)CS)C(C)C)=O

Technical Data

Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code:


1: Cox AD, Garcia AM, Westwick JK, Kowalczyk JJ, Lewis MD, Brenner DA, Der CJ. The CAAX peptidomimetic compound B581 specifically blocks farnesylated, but not geranylgeranylated or myristylated, oncogenic ras signaling and transformation. J Biol Chem. 1994 Jul 29;269(30):19203-6. PubMed PMID: 8034681.

2: Garcia AM, Rowell C, Ackermann K, Kowalczyk JJ, Lewis MD. Peptidomimetic inhibitors of Ras farnesylation and function in whole cells. J Biol Chem. 1993 Sep 5;268(25):18415-8. PubMed PMID: 8360140.