Sodium 2-(4-Oxo-3,4-dihydro-2-quinazolinylmethyl)benzoate. The quinazolinone 4a (1.4 g, 5 mmol)
was dissolved in 2N NaOH (5 ml) at room temperature. The solidified mixture was treated with i-PrOH and the
precipitate was filtered off and washed with Et2O. Yield 2 g (80%); mp 280°C (water). IR spectrum (KBr),
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ν, cm-1: 1620 (C=N), 1665 (C=O), 3420 (N–H). H NMR spectrum (DMSO-d6), δ, ppm, J (Hz): 15.3 (1H, s,
NH); 8.05 (1H, d, Jo = 8, 5-H); 7.1-7.8 (7H, m, Harom.); 4.1 (2H, s, CH2). Found, %: C 60.17; H 5.13; N 8.93.
C16H11N2NaO3. Calculated, %: C 63.58; H 3.67; N 9.27.
2-(1-Oxo-1,2-dihydro-3-isoquinolinylamino)benzoic Acid (3b). A mixture of 3-methoxy-1,2-dihydro-
1-isoquinoline (0.9 g, 5 mmol) and anthranilic acid (0.7 g, 5 mmol) was refluxed for 4 h in chlorobenzene
(10 ml). The precipitate was filtered off and washed with i-PrOH and Et2O. Yield 0.84 g (60%); mp 276°C
(DMF). IR spectrum (KBr), ν, cm-1: 1650 (sh.), 1635 (C=O). 1H NMR spectrum (DMSO-d6), δ, ppm: 13.2 (1H,
s, OH); 11.9 (1H, s, C(3)NH); 9.5 (1H, s, N(2)H); 6.9-8.0 (8H, m, Harom.); 6.3 (1H, s, C(4)H). Found %: C 68.62;
H 4.38; N 10.05. C16H12N2O3. Calculated, %: C 68.57; H 4.32; N 9.99.
3-(1-Oxo-1,2-dihydro-3-isoquinolinamino)benzoic Acid (3c). A mixture of 2-cyanomethylbenzoic
acid (0.32 g, 2 mmol) and m-aminobenzoic acid (0.27 g, 2 mmol) was refluxed for 4 h in chlorobenzene (5 ml).
Solvent was removed in vacuo and the residue was treated with i-PrOH and the precipitate filtered off.
Yield 0.43 g (77%); mp 305°C (DMF). IR spectrum (KBr), ν, cm-1: 1630 (C=N); 1665 (C=O carboxyl group),
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1705 (C=O 4-quinazolinone), 2660-2960 (N+–H), 3280-3560 (O–H). H NMR spectrum (DMSO-d6), δ, ppm:
10.9 (1H, s, C(3)NH); 8.2 (1H, s, N(2)H); 7.1-8.1 (8H, m, Harom.); 6.1 (1H, s, C(4)H). Found, %: 68.59; H 4.40;
N 10.09. C16H12N2O3. Calculated, %: C 68.57; H 4.32; N 9.99.
3-(1,3-Benzodioxolan-5-ylamino)-1,2-dihydro-1-isoquinolinone (3d), A mixture of 2-cyanomethyl-
benzoic acid (0.32 g, 2 mmol) and 1,3-benzodioxolan-5-amine (0.54 g, 4 mmol) was refluxed for 2 h in
chlorobenzene (5 ml). The solvent was removed in vacuo and the residue treated with Et2O and filtered off.
Yield 0.4 g (73%); mp 235°C (i-PrOH). IR spectrum (KBr), ν, cm-1: 1630 (C=N), 1665 (C=O carboxyl group),
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1705 (C=O 4-quinazolinone), 2660-2960 (N+–H), 3280-3560 (O–H). H NMR spectrum (DMSO-d6), δ, ppm,
J (Hz): 5.8 (1H, s, C(4)–CH); 7.7 (1H, s, N(2)H); 6.6-7.5 (6H, m, Harom.); 8.0 (1H, d, Jo = 8, 8-H); 10.6 (1H, s,
C(3)–NH). Found, %: C 68.67; H 4.37; N 10.09. C16H12N2O3. Calculated, %: C 68.57; H 4.32; N 9.99.
Ethyl Ester of 2-(4-Oxo-3,4-dihydro-2-quinazolinylmethyl)benzoic Acid (5a). Quinazolinone 4a
(0.28 g, 1 mmol) was suspended in absolute EtOH (20 ml). SOCl2 (1 ml, 14 mmol) was added carefully
dropwise at 0-5°C. The reaction mixture was then refluxed for 5 h, solvent evaporated off in vacuo, and the
residue was treated with a saturated solution of NaHCO3. The residue was filtered off and washed with water,
i-PrOH, and Et2O. Yield 0.23 g (70%); mp 176°C (AcOH). IR spectrum (KBr), ν, cm-1: 1250 (C–O), 1610
(C=N), 1670 (C=O quinazolinone), 1710 (C=O ester), 3170 (N–H). 1H NMR spectrum (CDCl3), δ, ppm, J (Hz):
4.5 (2H, q, O–CH2); 4.3 (2H, s, CH2); 1.4 (3H, t, J = 3, CH3). Found, %: C 70.63 ;H 5.37; N 9.15. C18H16N2O3.
Calculated, %: C 70.12; H 5.23; N 9.09.
2-Oxo-2-phenylethyl Ester of 2-(4-Oxo-3,4-dihydro-2-quinazolinylmethyl)benzoic Acid (5b). The
sodium salt of 4a (1 g, 3 mmol) was dissolved in water (10 ml) and acidified with two drops of dilute HCl.
EtOH (10 ml) was added and then phenacyl bromide (1 g, 5 mmol). The reaction mixture was heated with a
reflux condenser on a water bath. After cooling, the precipitate was filtered off and washed with dilute NaHCO3
solution and Et2O. Yield 0.8 g (68%); mp 215°C (i-PrOH). IR spectrum (KBr), ν, cm-1: 1280 (C–O) 1605
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(C=N), 1660 (C=O quinazolinone), 1690, 1710 (C=O ester), 3170 (N–H). H NMR spectrum (CDCl3), δ, ppm:
4.6 (2H, s, CH2); 5.7 (2H, s, O–CH2); 7.3 (1H, s, NH); 7.4-8.3 (13H, m, Harom.). Found, %: C 72.57; H 4.73;
N 7.11. C24H18N2O4. Calculated, %: C 72.35; H 4.55; N 7.03.
2-Phenylhydrazide of 2-(4-Oxo-3,4-dihydro-2-quinazolinylmethyl)benzoic Acid (5c). A mixture of
acid 4a (1 g, 3.6 mmol) and phenylhydrazine (2 ml, 20 mmol) was heated in benzene (20 ml) using a reflux
condenser for 30 min. After cooling the reaction mixture the precipitate was filtered off and washed with Et2O.
Yield 0.9 g (70%); mp 273°C (AcOH). IR spectrum (KBr), ν, cm-1: 1605 (C=N), 1650-1670 (broad C=O
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