Benzocaine → 4-{[4-(5-chloro-2-methoxy-benzene-sulfonyl)-3,4-dihydro-2H-benzo[1,4]oxazine-6-carbonyl]-amino}-benzoic acid ethyl ester

A suspension of 4-(5-chloro-2-methoxy-benzenesulfonyl)-3,4-dihydro-2H-benzo[1,4]oxazine-6-carboxylic acid (1.0 g, 2.6 mmol) in acetone (130 mL) and tetrahydrofuran (30 mL) was treated with triethylamine (0.5 g, 0.68 mL, 1.9 equiv.) and stirred at room temperature overnight. A solution of cyanuric chloride (596 mg, 3.2 mmol, 1.24 equiv.) in acetone (20 mL) was added dropwise over a period of 1 hour. The reaction mixture was stirred at room temperature for 4 hours, 4-amino-benzoic acid ethyl ester (775 mg, 4.7 mmol, 1.8 equiv.) was then added. The reaction mixture was stirred at room temperature overnight, the solvents were then removed. The residue was purified by flash chromatography, to yield 4-{[4-(5-chloro-2-methoxy-benzenesulfonyl)-3,4-dihydro-2H-benzo[1,4]oxazine-6-carbonyl]-amino}-benzoic acid ethyl ester as a white solid, 0.91 g (66%). δH (300 MHz; CDCl3) 8.10 (1H, d), 8.03-8.07 (3H, m), 7.92 (1H, bs), 7.73 (2H, d), 7.70 (1H, d), 7.67 (1H, d), 7.53 (1H, d), 7.50 (1H, d), 4.37 (2H, q), 4.03 (2H, m), 3.88 (2H, m), 3.56 (3H, s), 1.40 (3H, t).

1. stirringThe reaction mixture was stirred at room temperature for 4 hours
2. stirringThe reaction mixture was stirred at room temperature overnight
3. customthe solvents were then removed
4. customThe residue was purified by flash chromatography

ORDレコード

ord-dd43304d0b884d518d000a3383ff86c5

出典データセット

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08030308B2