CCF0058981 (CCF981) is a 3-chlorophenyl analog and a non-covalent SARS-CoV-2 3CLpro (SC2) inhibitor (antagonist) with IC50 of 68 nM. CCF0058981 inhibits SC1 (SARS-CoV-1 3CLpro) with IC50 of 19 nM. CCF0058981 has antiviral efficacy and has potential usefulness in COVID-19 research.

Physicochemical Properties

Molecular Formula	C24H19CLN6O
Molecular Weight	442.90
Exact Mass	442.13
CAS #	2708934-53-4
PubChem CID	156027237
Appearance	Light brown to brown solid powder
LogP	4.2
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	6
Heavy Atom Count	32
Complexity	630
Defined Atom Stereocenter Count	0
SMILES	N1(CC(N(CC2=CC=CC(Cl)=C2)C2=CC=C(C3NC=NC=3)C=C2)=O)C2=CC=CC=C2N=N1
InChi Key	NQTRFDLUODRJKC-UHFFFAOYSA-N
InChi Code	InChI=1S/C24H19ClN6O/c25-19-5-3-4-17(12-19)14-30(20-10-8-18(9-11-20)22-13-26-16-27-22)24(32)15-31-23-7-2-1-6-21(23)28-29-31/h1-13,16H,14-15H2,(H,26,27)
Chemical Name	2-(benzotriazol-1-yl)-N-[(3-chlorophenyl)methyl]-N-[4-(1H-imidazol-5-yl)phenyl]acetamide
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	In vitro, CCF0058981 (CCF981) inhibits the cytopathic effect (CPE) of viral replication (EC50=497 nM) and reduces plaque (EC50=558 nM) [1]. According to the CPE antiviral assay, CCF0058981 has a 50% cytotoxic concentration (CC50) > 50 μM [1]. In human liver microsomes, the T1/2 of CCF0058981 is 21.1 minutes, and the CLlnt is 141 mL/min·kg[1].
References	[1]. Structure-Based Optimization of ML300-Derived, Noncovalent Inhibitors Targeting the Severe Acute Respiratory Syndrome Coronavirus 3CL Protease (SARS-CoV-2 3CL pro). J Med Chem. 2021 Aug 4;acs.jmedchem.1c00598.

Solubility Data

Solubility (In Vitro)

DMSO : ~25 mg/mL (~56.45 mM)

Solubility (In Vivo)

Solubility in Formulation 1: 2.5 mg/mL (5.64 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: 2.5 mg/mL (5.64 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.2578 mL	11.2892 mL	22.5785 mL
	5 mM	0.4516 mL	2.2578 mL	4.5157 mL
	10 mM	0.2258 mL	1.1289 mL	2.2578 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.