serine protease inhibitor

3,4-Dichloro-2-benzopyran-1-one, 3,4-DCI
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
Beilstein/REAXYS Number:
MDL number:
PubChem Substance ID:
Pricing and availability is not currently available.

Quality Level


≥98% (TLC)




ethyl acetate: 49.00-51.00 mg/mL, clear, colorless to faintly yellow

storage temp.


SMILES string




InChI key


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5, 10, 25 mg in glass bottle


Useful in a rapid staining method for identification of macrophages; counts by this method were confirmed by the more complex morphological criteria, by phagocytosis, and by the presence of Fc receptors.

Features and Benefits

This compound is also offered as part of Sigma′s Library of Pharmacologically Active Compounds (LOPAC®1280), a biologically annotated collection of high-quality, ready-to-screen compounds. Click here to learn more.

Other Notes

Effective concentration 5-100 μM.


Half-life = 20 min at pH 7.5.


Serine protease inhibitor. Active towards a wide range of serine proteases including granzymes. Not active toward β-lactamases.

Legal Information

LOPAC is a registered trademark of Sigma-Aldrich Co. LLC


Skull and crossbones

Signal Word


Hazard Statements

Target Organs

Respiratory system

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


UN 2811 6.1 / PGIII

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis
Certificate of Origin
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