ACCEPTED MANUSCRIPT
NH). 13C NMR (DMSO-d6): δ 110.00, 113.98, 115.01, 115.91, 120.82 (2C), 122.10, 126.05, 127.02, 130.37,
133.07, 139.56, 152.00, 157.8, 160.86 (2C). IR (Nujol) 3265, 1662, 1612, 1580 cm-1. m/z 282 (M + H)+. Anal.
Calcd for C16H12N2O3: C, 68.56; H, 4.32; N, 9.99. Found: C, 68.61; H, 4.33; N, 9.96.
5.2.3.3. (E)-N'-(2,4-dihydroxybenzylidene)benzofuran-2-carbohydrazide (5). Yield 74%. Mp 234 °C dec
1
(EtOH). H NMR (DMSO-d6): δ 6.32-6.38 (m, 2H, Ar), 7.32-7.38 (m, 2H, Ar), 7.51 (s, 1H, Ar), 7.70-7.81 (m,
3H, Ar), 8.59 (s, 1H, CH), 9.91 (s, 1H, OH), 11.20 (s, 1H, OH), 12.20 (s, 1H, NH). 13C NMR (DMSO-d6): δ
110.00, 110.57, 115.73, 118.45, 118.67, 119.65, 130.81, 131.78, 134.90, 135.11, 139.20, 155.71, 157.87,
162.05, 162.34, 167.42. IR (Nujol) 1627, 1610 cm-1. m/z 297 (M + H)+. Anal. Calcd for C16H12N2O4: C, 64.86;
H, 4.08; N, 9.46. Found: C, 64.91; H, 4.06; N, 9.50.
5.2.3.4. (E)-N'-(2,5-dihydroxybenzylidene)benzofuran-2-carbohydrazide (6). Yield 54%. Mp >250 °C (EtOH).
1H NMR (DMSO-d6): δ 6.72 (d, J= 7.0 Hz, 2H, Ar), 7.01 (s, 1H,Ar), 7.35-7.38 (m, 2H, Ar), 7.70-7.83 (m, 3H,
Ar), 8.66 (s, 1H, CH), 9.00 (s, 1H, OH), 10.20 (s, 1H, OH), 12.29 (s, 1H, NH). 13C NMR (DMSO-d6): δ 109.99,
118.84, 119.77, 121.47 (2C), 125.05, 127.00, 127.12, 130.85, 131.90, 134.88, 135.18, 152.20, 157.84,
158.16, 162.37. IR (Nujol) 1661, 1597 cm-1. m/z 297 (M + H)+. Anal. Calcd for C16H12N2O4: C, 64.86; H, 4.08;
N, 9.46. Found: C, 64.80; H, 4.07; N, 9.43.
5.2.3.5. (E)-N'-(2,3,4-trihydroxybenzylidene)benzofuran-2-carbohydrazide (7). Yield 53%. Mp >250 °C
1
(EtOH). H NMR (DMSO-d6): δ 6.40 (d, J=8.5 Hz, 1H, Ar), 6.80 (d, J=8.5 Hz, 1H, Ar), 7.35-7.81 (m, 5H, Ar),
8.55 (s, 1H, CH), 9.82 (s, 1H, OH), 11.20 (s, 1H, OH), 12.15 (s, 1H, NH), 13.10 (s, 1H, OH). 13C NMR (DMSO-
d6): δ 109.9 (2C), 115.68, 118.78, 119.77, 129.13, 130.83, 131.81, 134.90, 135.15, 140.65, 155.48, 155.66,
156.88, 162.05, 162.35. IR (Nujol) 3341, 1655, 1595 cm-1. m/z 313 (M + H)+. Anal. Calcd for C16H12N2O5: C,
61.54; H, 3.87; N, 8.97. Found: C, 61.59; H, 3.86; N, 9.01.
5.2.3.6. (E)-N'-(2,4,6-trihydroxybenzylidene)benzofuran-2-carbohydrazide (8). Yield 60%. Mp 248 °C dec
(EtOH). 1H NMR (DMSO-d6): δ 5.85 (s, 2H, Ar), 7.34-7.80 (m, 5H, Ar), 8.87 (s, 1H, CH), 9.83 (s, 1H, OH), 11.03
(s, 2H, OH), 12.24 (s, 1H, NH). 13C NMR (DMSO-d6): δ 97.56 (2C), 102.23, 113.78, 115.00, 126.04, 127.01,
130.15, 130.24, 140.30, 150.88, 157.04, 157.58 (2C), 162.98, 164.98. IR (Nujol) 3341, 1655, 1596 cm-1. m/z
313 (M + H)+. Anal. Calcd for C16H12N2O5: C, 61.54; H, 3.87; N, 8.97. Found: C, 61.49; H, 3.86; N, 8.94.
5.2.3.7. (E)-N'-(4-hydroxy-3-methoxybenzylidene)benzofuran-2-carbohydrazide (9). Yield 84%. Mp 192-
193 °C (EtOH). 1H NMR (DMSO-d6): δ 3.81 (s, 3H, OCH3), 6.99 (d, J=8.0 Hz, 1H, Ar), 7.07 (d, J=8.0 Hz, 1H, Ar),
7.30-7.81 (m, 6H, Ar), 8.38 (s, 1H, CH), 9.30 (s, 1H, OH), 12.01 (s, 1H, NH). 13C NMR (DMSO-d6): δ 56.75,
110.01, 113.72, 115.00, 115.07, 115.58, 123.65, 126.00, 126.98, 130.18, 130.27, 150.09, 152.07, 153.19,
153.78, 157.63, 160.60. IR (Nujol) 3230, 1643, 1609 cm-1. m/z 311 (M + H)+. Anal. Calcd for C17H14N2O4: C,
65.80; H, 4.55; N, 9.03. Found: C, 65.89; H, 4.54; N, 8.99.