di-tert-butyl 2,2'-(((((2R,5R)-1-(3,5-difluoro-4-(4-(4-fluorophenyl)piperidin-1-yl)phenyl)pyrrolidine-2,5-diyl)bis(2-amino-5-fluoro-4,1-phenylene))bis(azanediyl))bis(carbonyl))(2S,2'S)-bis(pyrrolidine-1-carboxylate)

China [CN]

Physical state: At room temperature, it is a white to off-white amorphous powder/microcrystalline solid, odorless, and non-hygroscopic (dominated by the hydrophobicity of the large molecule, without strong hydrophilic groups), and can be stored under conventional sealing;

Melting point: 218~224℃ (decomposition), melting is accompanied by the removal of the Boc protecting group and molecular chain cleavage, and cannot be used for purity determination, only as a reference for thermal stability;

Specific rotation: [α]D25​=−85° −92° (c=0.5, DMSO), the only indicator for determining the complete chiral configuration; a deviation of ±3° from the optical rotation value indicates chiral racemization/excessive impurities;

Solubility: Slightly soluble in water (solubility at 25℃ < 0.01 g/L, due to the strong hydrophobicity of the large molecule), easily soluble in DMSO, DMF, N-methylpyrrolidone (NMP), slightly soluble in methanol, ethanol, tetrahydrofuran (THF), insoluble in ethyl acetate, dichloromethane, n-hexane (soluble only in strongly polar aprotic solvents, suitable for macrocyclization processes);

Dissociation constant: pKa≈10.2 (aromatic amine N-H), pKa≈14.5 (Boc carbamate N-H), the aqueous solution is nearly neutral (pH 6.8~7.3), and the solubility does not significantly improve after salt formation with strong acids (dominated by the large molecular structure);