Ethyl 5-amino-4-phenylisoxazole-3-carboxylate

The ethyl ester obtained in Example phenylpropyl derivative 1 (12mmol), hydroxylamine hydrochloride (1.66g, 24mmol) and 70mLEthanol, heated at reflux for 12h, evaporated under reduced pressure to remove the ethanol stream. 50mL of ethyl acetate was then added and 10mL10percent sodium carbonate solution, the organic phase was separated, then washed with saturated brine, dried over anhydrous sodium sulfate, and ethyl acetate was evaporated under reduced pressure stream to yield a white powdery solid 2.48g. Yield 89.11percent.5-amino-obtained The 4-phenyl-isoxazole-3-carboxylic acid ethyl ester A1 (0.464g, 2mol), benzaldehyde(0.212g, 2mol) and 10mL absolute ethanol, was added one drop of concentrated sulfuric acid as a catalyst, was heated to reflux, TLC monitoring of the reaction, After completion of the reaction, cooled to room temperature, suction filtered, washed with water and purified by column chromatography to give a white powdery solid 0.45g. Yield 71.77%.The ethyl ester obtained in Example phenylpropyl derivative 1 (12mmol), hydroxylamine hydrochloride (1.66g, 24mmol) and 70mLEthanol, heated at reflux for 12h, evaporated under reduced pressure to remove the ethanol stream. 50mL of ethyl acetate was then added and 10mL10% sodium carbonate solution, the organic phase was separated, then washed with saturated brine, dried over anhydrous sodium sulfate, and ethyl acetate was evaporated under reduced pressure stream to yield a white powdery solid 2.48g. Yield 89.11%.5.0 % (15.1 mmol) of t-butyl [2-(4-phenyl-3-isoxazolecarboxamido)ethyl]carbamate were stirred at room temperature for 16 hours with trifluoroacetic acid analogously to Example 13. After concentration there was obtained a residue which was converted into the hydrochloride. Recrystallization of the crude product from methanol/ether yielded 3.B g (94.1%) of N-(2-aminoethyl)4-phenyl-3-isoxazolecarboxamide hydrochloride as white crystals, melting point 211-212. The t-butyl [2-(4-phenyl-3-isoxazolecarboxamido)ethyl]carbamate used as the starting material was prepared as follows: In an analogous manner to that described in J. Org. Chem. 50 (13) 1985, 2372-2375, 7.6 g (32.72 mmol) of 5.0 g (23 mmol) of ethyl phenylcyanopyruvate were reacted according to the method described in Chem. Ber. 107 (1974) 2794-2795 and Ber. Deutsch. Chem. Ges. 33 (1900) 2592-2595. Whereby there was obtained in 69.7% yield

Molecular Weight:232.23
XLogP3:2.2
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:4
Exact Mass:232.08479225
Monoisotopic Mass:232.08479225
Topological Polar Surface Area:78.4
Heavy Atom Count:17
Complexity:267
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes