Ro 5212773 (EPPTB) is a potent and specific (TAAR1) antagonist (Ki 0.9 nM for mouse TAAR1) without significant effects on other TAARs. TAAR1 is a G protein-coupled receptor (GPCR) that is non-selectively activated by endogenous amino acid (AA) metabolites.

Physicochemical Properties

Molecular Formula	C20H21F3N2O2
Molecular Weight	378.39
Exact Mass	378.156
CAS #	1110781-88-8
PubChem CID	25175634
Appearance	White to off-white solid powder
LogP	5.094
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	5
Heavy Atom Count	27
Complexity	494
Defined Atom Stereocenter Count	0
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

Hippocampal pyramidal neurons' excitability is inhibited by Ro 5212773 (EPPTB). Additionally, EPPTB lowers seizure activity and epileptiform events (SLE) [1]. Inward rectifier K+ current activation mediated by TAAR1 is blocked by Ro 5212773 [2]. 1.5 μM β-phenylethylamine (IC50=27.5 nM) potently inhibits the production of cAMP induced by mouse TAAR1 activation. This is achieved by Ro 5212773. In the absence of TAAR1 agonist, Ro 5212773 dose-dependently lowers cAMP levels in HEK293 cells (IC50= 19 nM). Compared to rat (IC50= 4539 nM) and human (IC50= 7487 nM) TAAR1, EPPTB significantly more effectively inhibits the production of cAMP in mice [2].

References

[1]. The selective antagonist EPPTB reveals TAAR1-mediated regulatory mechanisms in dopaminergic neurons of the mesolimbic system. Proc Natl Acad Sci U S A. 2009;106(47):20081-20086.

Solubility Data

Solubility (In Vitro)

DMSO: 100 mg/mL (264.28 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.61 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 25.0 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	2.6428 mL	13.2139 mL	26.4278 mL
	5 mM	0.5286 mL	2.6428 mL	5.2856 mL
	10 mM	0.2643 mL	1.3214 mL	2.6428 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.