MI-503 (MI503) is a novel, orally bioavailable and potent Menin-MLL interaction inhibitor (IC50= 14.7 nM) with potential anticancer activity. Chromosomal translocations affecting mixed lineage leukemia gene (MLL) result in acute leukemias resistant to therapy. The leukemogenic activity of MLL fusion proteins is dependent on their interaction with menin, providing basis for therapeutic intervention.

Physicochemical Properties

Molecular Formula	C28H27F3N8S
Molecular Weight	564.6352
Exact Mass	564.203
CAS #	1857417-13-0
PubChem CID	91667931
Appearance	White to off-white solid powder
Density	1.5±0.1 g/cm3
Boiling Point	782.9±60.0 °C at 760 mmHg
Flash Point	427.3±32.9 °C
Vapour Pressure	0.0±2.7 mmHg at 25°C
Index of Refraction	1.712
LogP	4.08
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	10
Rotatable Bond Count	7
Heavy Atom Count	40
Complexity	908
Defined Atom Stereocenter Count	0
InChi Key	DETOMBLLEOZTMZ-UHFFFAOYSA-N
InChi Code	InChI=1S/C28H27F3N8S/c1-17-19(2-3-25-23(17)8-21(11-32)39(25)14-18-12-35-36-13-18)15-38-6-4-20(5-7-38)37-26-24-9-22(10-28(29,30)31)40-27(24)34-16-33-26/h2-3,8-9,12-13,16,20H,4-7,10,14-15H2,1H3,(H,35,36)(H,33,34,37)
Chemical Name	4-Methyl-1-(1H-pyrazol-4-ylmethyl)-5-[[4-[[6-(2,2,2-trifluoroethyl)thieno[2,3-d]pyrimidin-4-yl]amino]-1-piperidinyl]methyl]-1H-indole-2-carbonitrile
Synonyms	MI503 MI 503 MI-503
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	MI-503 forms hydrogen connections with Tyr276 by occupying the F9 and P13 pockets on menin. It also extends beyond the P13 pocket to make hydrogen bonds with Trp341 and Glu366. When MI-503 was applied to mouse bone marrow cells (BMC) that had been transformed with the mLL-AF9 oncogene, there was a noticeable growth inhibition (GI50 of 0.22 μM). After 7–10 days of treatment, MI–503 exhibits a considerable time-dependent cell growth inhibitory impact [1].
ln Vivo	After a single intravenous or oral dosage, MI-503 exhibits significant levels in peripheral blood and a high oral bioavailability of 75%. MI-503 administered intraperitoneally (ip) once day significantly reduces the growth of tumors. Two mice that received MI-503 treatment had total tumor regression and a reduction in MV4;11 tumor volume of more than 80%. Ten days of continuous MI-503 treatment greatly slowed the MLL leukemia progression in mice and greatly decreased the burden of leukemic tumors. The expression of Hoxa9 and Meis1, two downstream targets of MLL fusion proteins that are markedly elevated in MLL leukemia, was considerably reduced upon treatment with MI-503 and MI-463 [1].
Cell Assay	Leukemia cells are treated with MI-503 or 0.25% DMSO and cultured at 37 °C for 7 days. Media is changed at day 4, viable cell numbers are restored to the original concentration and MI-503 are re-supplied. MTT cell proliferation assay kit is then employed, and plates are read for absorbance at 570 nm using a microplate reader[1].
References	[1]. Pharmacologic inhibition of the Menin-MLL interaction blocks progression of MLL leukemia in vivo. Cancer Cell. 2015 Apr 13;27(4):589-602.

Solubility Data

Solubility (In Vitro)

DMSO : ~25 mg/mL (~44.28 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (3.68 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 (3.68 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	1.7710 mL	8.8552 mL	17.7104 mL
	5 mM	0.3542 mL	1.7710 mL	3.5421 mL
	10 mM	0.1771 mL	0.8855 mL	1.7710 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.