Tanshinone IIA anhydride 

Tanshinone IIA anhydride, present in root extracts of Salvia miltiorrhiza, acts as an inhibitor of human carboxylesterase (CE). Tanshinone IIA anhydride has a K_i value of 1.9 nM against hCE1 and a K_i value of 1.4 nM against hiCE. Tanshinone IIA anhydride forms a stable covalent complex with serine Ser221 at the active site of hCE1, blocking the catalytic cycle of carboxylesterase, and the activity of the inactivated enzyme cannot recover spontaneously. Tanshinone IIA anhydride is applicable in metabolism-related studies^[1].

Ki: 1.9 nM (Human carboxylesterase (CE)) and 1.4 nM (human intestinal CE)^[1]

Tanshinone IIA anhydride (compound 4) potently and selectively inhibits recombinant human hCE1 (K_i = 1.9 nM) and hiCE (K_i = 1.4 nM)^[1].
Tanshinone IIA anhydride (10 μM; 100 μM PMSF) forms a covalent adduct with the catalytic serine residue of recombinant human hCE1, as evidenced by mass shifts and blocked adduction in the presence of the serine-inactivating agent PMSF^[1].
Tanshinone IIA anhydride (10 μM; 10 min) is cell-permeable and inhibits intracellular hCE1 activity in U373MG cells, reducing oseltamivir hydrolysis to 27% of control levels^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

310.34

C₁₉H₁₈O₄

61077-78-9

Solid

Light yellow to yellow

CC1(CCCC2=C1C=CC3=C2C(OC(C4=C3OC=C4C)=O)=O)C

Room temperature in continental US; may vary elsewhere.

4°C, protect from light

*In solvent : -80°C, 6 months; -20°C, 1 month (protect from light)

• [1]. Hatfield MJ, et al. Potent, Irreversible Inhibition of Human Carboxylesterases by Tanshinone Anhydrides Isolated from Salvia miltiorrhiza ("Danshen"). J Nat Prod. 2018;81(11):2410-2418.  [Content Brief]