AZD4573 (AZD-4573) is a novel, potent and short acting inhibitor of serine/threonine CDK9 (cyclin-dependent kinase 9, IC50<0.004 μM) with potential anticancer activities. It has strong selectivity against other kinases, including those in the CDK family, and fast-off binding kinetics (t1/2 = 16 min). A variety of anti-apoptotic proteins' gene transcription is inhibited when AZD4573 binds to CDK9 and inhibits its phosphorylation and kinase activity. This prevents PTEFb-mediated activation of RNA Pol II.

Physicochemical Properties

Molecular Formula	C22H28CLN5O2
Molecular Weight	429.9430
Exact Mass	429.19
Elemental Analysis	C, 61.46; H, 6.56; Cl, 8.25; N, 16.29; O, 7.44
CAS #	2057509-72-3
Related CAS #	2057509-72-3;Unknown (HCl);
PubChem CID	124155204
Appearance	White to off-white solid powder
LogP	2.7
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Heavy Atom Count	30
Complexity	659
Defined Atom Stereocenter Count	2
SMILES	CC(=O)N[C@@H]1CCC[C@@H](C1)C(=O)NC2=NC=C(C(=C2)C3=C4CC(CN4N=C3)(C)C)Cl
InChi Key	AVIWDYSJSPOOAR-LSDHHAIUSA-N
InChi Code	InChI=1S/C22H28ClN5O2/c1-13(29)26-15-6-4-5-14(7-15)21(30)27-20-8-16(18(23)11-24-20)17-10-25-28-12-22(2,3)9-19(17)28/h8,10-11,14-15H,4-7,9,12H2,1-3H3,(H,26,29)(H,24,27,30)/t14-,15+/m0/s1
Chemical Name	(1S,3R)-3-acetamido-N-[5-chloro-4-(5,5-dimethyl-4,6-dihydropyrrolo[1,2-b]pyrazol-3-yl)pyridin-2-yl]cyclohexane-1-carboxamide
Synonyms	AZD-4573; AZD4573; AZD 4573
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

Targets	CDK9 (IC50 = 4 nM)
ln Vitro	AZD4573 treatment for a brief period of time resulted in a fast dose- and time-dependent reduction in cellular pSer2-RNAPII, which in turn activated caspase 3 and induced cell death in a variety of haematological cancer cell lines (for example, caspase activation EC50 13.7 nM in an acute myeloid leukemia model MV4-11) [1].
ln Vivo	AZD4573 has a short half-life (less than an hour in the case of rats, dogs, and monkeys) and is well soluble when administered intravenously[1].
Cell Assay	Specific drug concentrations were applied to the cells.
Animal Protocol	Nomo-1 AML xenograft 5 mg/kg i.p.
References	[1]. Abstract 1650: Discovery of AZD4573, a potent and selective inhibitor of CDK9 that enables transient target engagement for the treatment of hematologic malignancies. Cancer Research. July 2018. 78(13): Supplement.
Additional Infomation	Zemirciclib is a selective, short-acting inhibitor of the serine/threonine cyclin-dependent kinase 9 (CDK9), the catalytic subunit of the RNA polymerase II (RNA Pol II) elongation factor positive transcription elongation factor b (PTEF-b; PTEFb), with potential antineoplastic activity. Upon intravenous administration, zemirciclib binds to and blocks the phosphorylation and kinase activity of CDK9, thereby preventing PTEFb-mediated activation of RNA Pol II, leading to the inhibition of gene transcription of various anti-apoptotic proteins. This induces cell cycle arrest and apoptosis, and leads to a reduction in tumor cell proliferation. CDK9 regulates elongation of transcription through phosphorylation of RNA polymerase II at serine 2 (p-Ser2-RNAPII). It is upregulated in various tumor cell types and plays a key role in the regulation of Pol II-mediated transcription of anti-apoptotic proteins. Tumor cells are dependent on anti-apoptotic proteins for their survival.

Solubility Data

Solubility (In Vitro)

DMSO: ≥ 80mg/mL Water: < 1mg/mL Ethanol: < 1mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (4.84 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 20.8 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 2: ≥ 2.08 mg/mL (4.84 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 3: ≥ 2.08 mg/mL (4.84 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.3259 mL	11.6295 mL	23.2591 mL
	5 mM	0.4652 mL	2.3259 mL	4.6518 mL
	10 mM	0.2326 mL	1.1630 mL	2.3259 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.