Ethyl 2-hydroxy-1,8-naphthyridine-3-carboxylate

2-Amino-3-pyridine carboxaldehyde (1.0 g, 8.19 mmol) was suspended in diethylmalonate (6.2 ml, 41.0 mmol) in a screw cap pressure tube. Piperidine (1.6 ml, 16.4 mmol) was added and the tube was sealed. The mixture was heated to 120Ethyl 2-oxo-1, 2-dihydro-1, 8-naphthyridine-3-carboxylate2-amino-3-formylpyridine (CAS registration No.: 7521-41-7) (1.0 g) was dissolved in ethanol (20 mL), anddiethyl malonate (3.4 mL), piperidine (2.4 mL), and acetic acid (0.052 mL) were added thereto. The resulting mixturewas refluxed for 18 hours. The reaction solution was left to cool to room temperature, and then the solvent was distilledoff by concentration under reduced pressure. The obtained residue was washed with water to obtain the title compound(1.5 g) having the following physical property value.1H-NMR (CDCl3): δ 1.43, 4.45, 7.26-7.29, 8.04, 8.47, 8.87, 12.24(2)General procedure: Anhydrous FeCl3 (0.05 mmol) was added to a stirred solution of 2-aminonicotinaldehyde (1, 0.01 mmol) and Meldrum’s acid (2, 0.01 mmol) in alcohol 3a–3k(3 mL). The mixture was heated on an oil bath at 60–80°C for 6-8 h. The mixture was then cooled down to room temperature, and excess alcohol was removed under reduced pressure. The residue was purified by column chromatography on silica gel with ethylacetate and petroleum ether (1 : 6, v/v) as eluent. Th eyields and melting points of compounds 4a–4k are given in Table 1.

Molecular Weight:218.21
XLogP3:1
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:3
Exact Mass:218.06914219
Monoisotopic Mass:218.06914219
Topological Polar Surface Area:68.3
Heavy Atom Count:16
Complexity:338
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes