• USA Home
  • A6191 - Antipain dihydrochloride from microbial source

A6191 Sigma-Aldrich

Antipain dihydrochloride from microbial source

protease inhibitor

Synonym: N-(Nα-Carbonyl-Arg-Val-Arg-al)-Phe

  • CAS Number 37682-72-7

  • Empirical Formula (Hill Notation) C27H44N10O6 · 2 HCl

  • Molecular Weight 677.62

  •  MDL number MFCD00135957

  •  PubChem Substance ID 24891067



Related Categories A to C, Aldehydes, Antibiotics, Antibiotics by Application, Antineoplastic and Immunosuppressive Antibiotics,
Quality Level   300
biological source   Streptomyces sp.
form   lyophilized powder
potency   1.4 μM Ki
solubility   H2O: 50 mg/mL
  1-butanol: soluble
  1-propanol: soluble
  DMSO: soluble
  ethanol: soluble
  methanol: soluble
Mode of action   enzyme | inhibits
storage temp.   −20°C
SMILES string   Cl[H].Cl[H].[H]C(=O)C(CCCNC(N)=N)NC(=O)[C@@H](NC(=O)[C@H](CCCNC(N)=N)NC(=O)NC(Cc1ccccc1)C(O)=O)C(C)C
InChI   1S/C27H44N10O6.2ClH/c1-16(2)21(23(40)34-18(15-38)10-6-12-32-25(28)29)37-22(39)19(11-7-13-33-26(30)31)35-27(43)36-20(24(41)42)14-17-8-4-3-5-9-17;;/h3-5,8-9,15-16,18-21H,6-7,10-14H2,1-2H3,(H,34,40)(H,37,39)(H,41,42)(H4,28,29,32)(H4,30,31,33)(H2,35,36,43);2*1H/t18?,19-,20?,21-;;/m0../s1


General description

Chemical structure: peptide


Antipain dihydrochloride from microbial source has been used in the preparation of adipocyte proteins for western blotting and in protease inhibitor cocktail for isolating nuclear extracts for gelshift analysis.

Concentrations for 50% inhibition (μg/ml):
papain, 0.16
trypsin, 0.26
cathepsin A, 1.19
cathepsin B, 0.59
cathepsin D, 125
plasmin, >93
chymotrypsin and pepsin, >250
It also has been reported to inhibit calpain I, (porcine) with Ki = 1.4 μM


1, 5, 25, 100 mg in glass bottle

Biochem/physiol Actions

Antipain dihydrochloride also inhibits the action of papain and cathespsin B.

Reversible inhibitor of serine/cysteine proteases and some trypsin-like serine proteases. Its action resembles leupeptin; however, its plasmin inhibition is less and its cathepsin A inhibition is more than that observed with leupeptin. Chronic administration of antipain can reduce the frequency of chemically induced transformation in BALB/c-/3T3 cells.

Preparation Note

Solubility testing at 50 mg/ml in water yields a clear to slightly hazy yellow solution. It is reportedly soluble in methanol, water, and DMSO; less soluble in ethanol, butanol, and propanol; insoluble in benzene, hexane, and chloroform.8 A stock solution in water or buffer is stable for about a month at -20 °C.

Dilute solutions should be stored on ice and kept for only a day because of the terminal aldehyde, which is subject to oxidation and racemization.

Stock solutions in water or buffer stable for 1 week at 4 °C, 1 month at −20 °C.

Safety & Documentation

Safety Information

Personal Protective Equipment 
NONH for all modes of transport
WGK Germany 


Certificate of Analysis (COA)

Please Enter a Lot Number

Certificate of Origin (COO)

Please Enter a Lot Number

Meet Synthia - Retrosynthesis Sofware

Single- & multi-channel pipettes from BRAND
Protocols & Articles
Peer-Reviewed Papers


Related Products

Technical Service:

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Bulk Ordering & Pricing:

Need larger quantities for your development, manufacturing or research applications?