SARS-CoV-2 3CLpro-IN-38 

SARS-CoV-2 3CLpro-IN-38 is a 3CLpro inhibitor with an IC₅₀ of 0.34 μM against SARS-CoV-2 3CLpro and an IC₅₀ of 0.12 μM against MERS-CoV 3CLpro. SARS-CoV-2 3CLpro-IN-38 inhibits recombinant Cathepsin L with an IC₅₀ of 5.23 nM. SARS-CoV-2 3CLpro-IN-38 inhibits cysteine proteases essential for the replication of SARS-CoV-2 and MERS-CoV, suppresses host cysteine proteases involved in coronavirus entry, blocks viral entry, and inhibits viral replication. SARS-CoV-2 3CLpro-IN-38 can be used in the research of COVID-19^[1].

SARS-CoV-2 3CLpro-IN-38 (Compound 1) (Serial dilutions; 1 h enzyme incubation, 1 h substrate incubation) potently inhibits SARS-CoV-2 3CLpro (Wuhan-Hu-1) with an IC₅₀ of 0.34 μM^[1].
SARS-CoV-2 3CLpro-IN-38 (Serial dilutions; 1 h enzyme incubation, 1 h substrate incubation) potently inhibits MERS-CoV 3CLpro (EMC/2012) with an IC₅₀ of 0.12 μM^[1].
SARS-CoV-2 3CLpro-IN-38 potently inhibits recombinant human cathepsin L with an IC₅₀ of 5.23 nM^[1].
SARS-CoV-2 3CLpro-IN-38 (0.02-2 μM; 30 h) potently inhibits SARS-CoV-2 (Wuhan-Hu-1) replicon in 293T cells with an EC₅₀ of 0.06 μM^[1].
SARS-CoV-2 3CLpro-IN-38 (1-100 μM; 72 h) exhibits low cytotoxicity in 293T cells, with a CC₅₀ > 100 μM and a selectivity index of ~1667^[1].

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

580.61

C₂₇H₄₁N₄O₈P

[H]C([C@@H](NC([C@@H](NC(OC[C@@H]1COP(OC(C)C)(N1CC2=CC=CC=C2)=O)=O)CC(C)C)=O)C[C@@H]3CCNC3=O)=O

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Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Nguyen HN, et al. Structure-guided design of broad-spectrum inhibitors of coronaviral proteases embodying a 1,3,2-oxazaphospholidin-3-one scaffold as a versatile design element. European journal of medicinal chemistry. 2026 May 26;316:119002.  [Content Brief]