Zidebactam (WCK-5107; WCK5107) is a potent β-lactamase inhibitor and also a penicillin-binding protein2 (PBP2) inhibitor with an IC50 of 0.26 μg/mL. It is one of the components ot WCK 5222 (Cefepime-Zidebactam) which is a bicyclo-acyl hydrazide β-lactam enhancer antibiotic with a dual action involving binding to Gram-negative bacterial PBP2 and β-lactamase inhibition. Cefepime/zidebactam demonstrated excellent activity against Enterobacteriaceae and P. aeruginosa, although activity was reduced in carbapenem-non-susceptible isolates. The activity against A. baumannii was reduced and studies examining the therapeutic efficacy in strains with high cefepime/zidebactam MICs are warranted.

Physicochemical Properties

Molecular Formula	C13H21N5O7S
Molecular Weight	391.4
Exact Mass	391.116
Elemental Analysis	C, 39.89; H, 5.41; N, 17.89; O, 28.61; S, 8.19
CAS #	1436861-97-0
Related CAS #	Zidebactam sodium salt;1706777-46-9
PubChem CID	77846445
Appearance	White to off-white solid powder.
Density	1.6±0.1 g/cm3
Index of Refraction	1.653
LogP	-3.01
Hydrogen Bond Donor Count	4
Hydrogen Bond Acceptor Count	8
Rotatable Bond Count	4
Heavy Atom Count	26
Complexity	694
Defined Atom Stereocenter Count	3
SMILES	[N@]12C[C@H](N(OS(=O)(O)=O)C1=O)CC[C@H]2C(NNC([C@@H]1CCCNC1)=O)=O
InChi Key	YCZPXRQPDCXTIO-BBBLOLIVSA-N
InChi Code	InChI=1S/C13H21N5O7S/c19-11(8-2-1-5-14-6-8)15-16-12(20)10-4-3-9-7-17(10)13(21)18(9)25-26(22,23)24/h8-10,14H,1-7H2,(H,15,19)(H,16,20)(H,22,23,24)/t8-,9-,10+/m1/s1
Chemical Name	(1R,2S,5R)-7-oxo-2-(2-((R)-piperidine-3-carbonyl)hydrazine-1-carbonyl)-1,6-diazabicyclo[3.2.1]octan-6-yl hydrogen sulfate
Synonyms	WCK-5107; WCK 5107; WCK5107; Zidebactam
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	Zidebactam (WCK-5107) has a MIC50 of 0.25 mg/L and inhibits WT Enterobacteriaceae. When tested against E. coli (MIC50/90 0.12/0.12 mg/L) and Enterobacter spp. (MIC50/90 0.12/0.25 mg/L), zebebactam alone exhibited varied efficacy [1].
References	[1]. WCK 5222 (cefepime/zidebactam) antimicrobial activity tested against Gram-negative organisms producing clinically relevant β-lactamases. J Antimicrob Chemother. 2017 Jun 1;72(6):1696-1703. [2]. WCK 5107 (Zidebactam) and WCK 5153 Are Novel Inhibitors of PBP2 Showing Potent "β-Lactam Enhancer" Activity against Pseudomonas aeruginosa, Including Multidrug-Resistant Metallo-β-Lactamase-Producing High-Risk Clones. Antimicrob Agents Chemother. 2017 May 24;61(6).
Additional Infomation	Zidebactam is under investigation in clinical trial NCT02674347 (MAD Study to Evaluate the Safety, Tolerability and Pharmacokinetics of Intravenous Zidebactam in Healthy Adults).

Solubility Data

Solubility (In Vitro)

DMSO : ~250 mg/mL (~638.73 mM) H2O : ~100 mg/mL (~255.49 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (5.31 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 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. Solubility in Formulation 2: ≥ 2.08 mg/mL (5.31 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly. Solubility in Formulation 3: ≥ 1.98 mg/mL (5.06 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 19.8 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 4: 100 mg/mL (255.49 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication (<60°C).  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.5549 mL	12.7747 mL	25.5493 mL
	5 mM	0.5110 mL	2.5549 mL	5.1099 mL
	10 mM	0.2555 mL	1.2775 mL	2.5549 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.