W. S. Hamama, G. G. El-Bana, S. Shaaban, and H. H. Zoorob
Vol 000
4-Amino-6-benzyl-3-((4-hydroxy-3-methoxybenzylidene)
(588.63): C, 65.30; H, 4.79; N, 19.04%. Found: C, 65.27;
hydrazono)-3,4-dihydro-1,2,4-triazin-5(2H)-one (4b).
The
H, 4.81; N, 19.01%.
aldehyde used was 4-hydroxy-3-methoxy benzaldehyde.
Yellow powder (0.67 g, 85%) (6 h reflux); mp 180–
181°C; [ethanol]; Rf = 0.28 [pet. ether (60:80)/ethyl
acetate (4:2)]; IR (KBr): ν/cmꢀ1 = 3328 (OH), 3265,
3245 (NH2), 3176 (NH), 2910 (CH2), 1663 (C═O
amide), and 1660 (C═C); 1H NMR (DMSO-d6) δ
(ppm): 3.85 (s, 2H, CH2–Ph), 3.88 (s, 3H, O–CH3),
5.75 (s, 2H, NH2), 6.79–7.74 (m, 8H, Ar–H), 8.17 (s,
1H, ═CH), 9.35 (br, 1H, OH), 12.23 (br, 1H, NH); MS
(EI, 70 eV) m/z (%) = 367 (M+ +1, 20.1), 366 (87.9),
351 (14.2), 218 (12.3), 217 (29.4), 150 (40.5), 136
(76.1), 117 (17.6), 116 (40.0), 91 (100.0), 77 (16.5), 76
(5.4), 51 (4.9). Anal. Calcd for C18H18N6O3 (366.38):
4-(2-Acetyl-8-(N-acetylacetamido)-6-benzyl-7-oxo-2,3,7,8-
tetrahydro-1,2,4-triazolo[4,3-b]1,2,4-triazin-3-yl)-2-
methoxyphenyl acetate (5b). Yellow powder (1 g, 75%);
mp 195–197°C; [ethyl acetate]; Rf = 0.50 [pet. ether (60–
80)/ethyl acetate (4:2.5)]; IR (KBr): ν/cmꢀ1 = 2915
(CH2), 1770 (OCO–CH3), 1647 (O═C–CH3), 1643 (C═O
1
amide), and 1660 (C═C); H NMR (DMSO-d6) δ (ppm):
2.03 (s, 3H, CH3triazole), 2.31 (s, 3H, CH3–COO), 2.35 (s,
3H, CH3), 2.48 (s, 3H, CH3), 3.81 (s, 2H, CH2–Ph), 3.84
(s, 3H, O–CH3), 7.01–7.26 (m, 9H, Ar–H + CH–
triazole); 13C NMR (DMSO-d6) δ: 20.73 (1C,
OCO–CH3), 20.79 (1C, O═C–CH3), 23.99 (1C,
O═C–CH3), 24.92 (1C, O═C–CH3), 36.52 (1C, CH2–
Ph), 56.05 (1C, O–CH3), 76.66 (1C, C-3`), 110.84 (1C,
CAr), 119.43 (1C, CHAr), 123.12 (1C, CHAr), 127.04 (1C,
CHAr), 128.58 (2C, CHAr), 128.76 (2C, CAr), 134.02 (1C,
CAr), 138.56 (1C, CAr), 140.94 (1C, CAr), 143.12 (1C, C-
3), 144.48 (1C, C-6), 151.52 (1C, CAr), 167.39 (2C,
C═O), 168.45 (1C, COO), 168.74 (2C, C═O); MS (EI,
70 eV) m/z (%) = 535 (M+ +1, 29.5), 534 (100.0), 492
(71.8), 451 (16.2), 450 (89.6), 449 (12.2), 434 (3.6), 433
(9.9), 408 (27.0), 407 (19.9), 392 (20.5), 391 (38.3), 366
(2.9), 365 (3.5), 302 (2.5), 285 (10.6), 260 (15.5), 218
(8.6), 150 (25.0), 149 (15.7), 136 (32.5), 117 (6.1), 116
(10.1), 91 (83.7), 77 (8.8), 76 (2.3), 52 (1.9), 51 (3.5), 50
(1.0). Anal. Calcd for C26H26N6O7 (534.53): C, 58.42; H,
C, 59.01; H, 4.95; N, 22.94%. Found: C, 59.03; H,
4.92; N, 22.97%.
4-Amino-6-benzyl-3-(((2-hydroxynaphthalen-1-yl)methylene)
hydrazono)-3,4-dihydro-1,2,4-triazin-5(2H)-one (4c).
The
aldehyde used was 2-hydroxy naphthaldehyde.
Yellow powder (0.72 g, 87%) (4 h reflux); mp 228–
229°C; [DMF]; Rf = 0.47 [pet. ether (60:80)/ethyl acetate
(4:2)]; IR (KBr): ν/cmꢀ1 = 3313 (OH), 3240, 3223
(NH2), 3186 (NH), 2910 (CH2), 1663 (C═O amide), and
1
1660 (C═C); H NMR (DMSO-d6) δ (ppm): 3.91 (s, 2H,
CH2–Ph), 5.87 (br s, 2H, NH2), 7.15–8.66 (m, 11H, Ar–
H), 9.40 (s, 1H, ═CH), 11.65 (br s, 1H, OH), 12.33 (br,
1H, NH); MS (EI, 70 eV) m/z (%) = 387 (M+ +1, 23.7),
386(100.0), 369 (22.2), 218 (60.2), 170 (36.7), 169
(75.6), 143 (5.2), 128 (95.4), 117 (13.0), 116 (44.8), 115
(60.9), 103 (6.2), 102 (10.7), 91 (50.4), 77 (9.2), 51 (1.9).
Anal. Calcd for C21H18N6O2 (386.42): C, 65.27; H, 4.70;
N, 21.75%. Found: C, 65.24; H, 4.73; N, 21.73%.
4.90; N, 15.72%. Found: C, 58.39; H, 4.88; N, 15.70%.
1-(2-Acetyl-8-(N-acetylacetamido)-6-benzyl-7-oxo-2,3,7,8-
tetrahydro-1,2,4-triazolo[4,3-b]1,2,4-triazin-3-yl)naphthalen-2-
yl)acetate (5c).
Yellow powder (1 g, 73%); mp 165–
166°C; [ethyl acetate]; Rf = 0.30 [pet. ether (60:80)/ethyl
acetate (4:3)]; IR (KBr): ν/cmꢀ1 = 2915 (CH2), 1764
(OCO–CH3), 1651 (O═C–CH3), 1644 (C═O amide), and
Effect of acetic anhydride on Schiff bases 5a–c. General
procedure: A solution of the corresponding Schiff bases
4a–c (2.5 mmol) in 6 mL acetic anhydride was heated
under reflux for 12 h. The reaction mixture was then
cooled and poured into crushed ice. The crude product
that precipitated was obtained by filtration, washed with
water (10 mL), and then recrystallized to afford 5a–c.
N-Acetyl-N-(2-acetyl-6-benzyl-3-(1,3-diphenyl-1H-pyrazol-4-
yl)-7-oxo-2,3-dihydro-1,2,4-triazolo[4,3-b]1,2,4-triazin-8(7H)-
yl)acetamide (5a). Yellow flakes (1.2 g, 79%); mp 160–
1
1660 (C═C); H NMR (DMSO-d6) δ (ppm): 1.98 (s, 3H,
CH3triazole), 2.49 (s, 3H, CH3–COO), 2.57 (s, 3H, CH3),
2.60 (s, 3H, CH3), 3.71 (s, 2H, CH2–Ph), 6.90–8.05 (m,
12H, Ar–H + CH–triazole); 13C NMR (DMSO-d6) δ:
17.83 (1C, OCO–CH3), 23.18 (1C, O═C–CH3), 25.96
(1C, O═C–CH3), 27.39 (1C, O═C–CH3), 38.20 (1C,
CH2–Ph), 67.59 (1C, C-3`), 123.32 (1C, CHAr), 123.43
(1C, CAr), 125.21 (1C, CHAr), 125.63 (1C, CHAr), 125.92
(1C, CHAr), 128.52 (2C, CHAr), 129.27 (1C, CHAr),
130.99 (2C, CHAr), 131.13 (2C, CHAr), 131.78 (1C, CAr),
134.43 (2C, CHAr), 135.05 (1C, CAr), 138.75 (1C, CAr),
147.65 (1C, C-3), 144.56 (1C, C-6), 153.96 (1C, CAr),
170.76 (1C, O–CO–CH3), 172.48 (2C, 2O═C–CH3); MS
(EI, 70 eV) m/z (%) = 554 (M+ 18.4), 512 (14.0), 511
(4.6), 496 (26.7), 468 (15.0), 454 (1.2), 452 (10.9), 411
(35.2), 369 (33.9), 325 (11.6), 283 (14.2), 225 (1.4), 223
(12.4), 186 (4.3), 185 (22.5), 171 (13.2), 170 (41.4), 169
(100.0), 117 (7.3), 116 (14.7), 115 (31.9), 91 (98.3), 77
(16.8), 52 (1.0), 51 (5.4), 50 (4.3). Anal. Calcd for
162°C; [ethyl acetate]; Rf = 0.50 [pet. ether (60–80)/ethyl
acetate (4:2)]; IR (KBr): ν/cmꢀ1 = 2910 (CH2), 1648
1
(O═C–CH3), 1644 (C═O amide), and 1660 (C═C); H
NMR (DMSO-d6) δ (ppm): 2.07 (s, 3H, CH3triazole), 2.37
(s, 3H, CH3), 2.40 (s, 3H, CH3), 3.80 (s, 2H, CH2–Ph),
7.12–7.78 (m, 16H, Ar–H + CH–triazole), 8.15 (s, 1H,
CH–pyrazole); MS (EI, 70 eV) m/z (%) = 589 (M+ +1,
68.7), 588 (79.4), 488 (32.9), 487 (100.0), 455 (8.9), 403
(8.6), 401 (23.6), 360 (7.9), 317 (17.7), 298 (10.0), 274
(12.5), 256 (18.7), 241 (16.5), 231 (18.7), 221 (10.1),
218 (1.1), 124 (31.0). Anal. Calcd for C32H28N8O4
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet