6
58
M. Weber et al.
ꢀ
1
M.p.: 203±205 C; H NMR ꢀCDCl , ꢁ, 300 MHz): 1.20±1.43 ꢀm, 4H, 2 CH ), 1.66 ꢀd,
3
2
J 7.1 Hz, 6H, 2 CH ), 2.27±2.39 ꢀm, 1H, CH), 5.90 ꢀsept, J 7.1 Hz, 1H, CH), 7.26 ꢀdd,
3
J 7.9 Hz, J 4.7 Hz, 1H, pyridine-H), 8.21 ꢀd, J 7.9 Hz, 1H, pyridine-H), 8.49 ꢀd, J 4.7 Hz,
1
3
H, pyridine-H), 8.59 ꢀs, 1H, imidazole-H) ppm; C NMR ꢀCDCl , ꢁ, 75 MHz): 7.7, 10.1, 19.5,
1
4
3
6.2, 116.9, 118.2, 120.6, 123.0, 131.7, 142.3, 146.4, 154.1, 163.4, 181.4 ppm; MS: m=z ꢀ%) 336
ꢀ
M , 5), 294 ꢀ11), 227 ꢀ15), 69 ꢀ100).
3
4
-#5-tert-Butyl-1,2,4-oxadiazol-3-yl)-5-isopropylimidazo[1,5-a]pyrido[2,3-e]pyrazine-
#5H)-one ꢀ10; C H N O )
8 20 6 2
1
The residue was recrystallized from petroleum ether=toluene to give 565 mg ꢀ80%) of 10 as white
crystals.
ꢀ
1
M.p.: 227±228 C; H NMR ꢀCDCl , ꢁ, 300 MHz): 1.53 ꢀs, 9H, 3 CH ), 1.67 ꢀd, J 6.8 Hz, 6H, 2
3
3
CH ), 5.91 ꢀsept, J 6.8 Hz, 1H, CH), 7.26 ꢀdd, J 7.9 Hz, J 4.7 Hz, 1H, pyridine-H), 8.17 ꢀd,
3
J 7.9 Hz, 1H, pyridine-H), 8.50 ꢀd, J 4.7 Hz, 1H, pyridine-H), 8.58 ꢀs, 1H, imidazole-H) ppm;
1
3
C NMR ꢀCDCl , ꢁ, 75 MHz): 19.5, 28.4, 33.6, 46.3, 116.9, 118.1, 120.7, 123.0, 131.9, 142.5,
3
1
46.4, 154.2, 163.2, 186.1 ppm; MS: m=z ꢀ%) 352 ꢀM , 4), 310 ꢀ10), 295 ꢀ9), 57 ꢀ100).
3
4
-#5-Cyclohexyl-1,2,4-oxadiazol-3-yl)-5-isopropylimidazo[1,5-a]pyrido[2,3-e]pyrazine-
#5H)-one ꢀ11; C H N O )
20 22 6 2
The residue was recrystallized from petroleum ether=toluene to give 576 mg ꢀ76%) of 11 as yellow
crystals.
ꢀ
1
M.p.: 220±222 C; H NMR ꢀCDCl , ꢁ, 300 MHz): 1.24±1.51 ꢀm, 3H, cyclohexyl-H), 1.66 ꢀd,
3
J 6.8 Hz, 6H, 2 CH ), 1.70±1.93 ꢀm, 5H, cyclohexyl-H), 2.10±2.24 ꢀm, 2H, cyclohexyl-H), 3.00±
3
3
.14 ꢀm, 1H, cyclohexyl-H), 5.90 ꢀsept, J 6.8 Hz, 1H, CH), 7.26 ꢀdd, J 8.1 Hz, J 4.7 Hz, 1H,
pyridine-H), 8.20 ꢀdd, J 8.1 Hz, J 1.3 Hz, 1H, pyridine-H), 8.49 ꢀdd, J 4.7 Hz, J 1.3 Hz,
1
H, pyridine-H), 8.61 ꢀs, 1H, imidazole-H) ppm; C NMR ꢀCDCl , ꢁ, 75 MHz): 19.5, 25.3, 25.4,
3
1
3
3
0.1, 36.3, 46.2, 116.9, 118.1, 120.6, 123.0, 131.9, 142.3, 146.4, 154.2, 163.3, 182.8 ppm; MS:
m=z ꢀ%) 378 ꢀM , 7), 336 ꢀ10), 227 ꢀ21), 55 ꢀ100).
5
4
-Isopropyl-3-#5-phenyl-1,2,4-oxadiazol-3-yl)-imidazo[1,5-a]pyrido[2,3-e]pyrazine-
#5H)-one ꢀ12; C H N O )
20 16 6 2
The residue was recrystallized from petroleum ether=toluene to give 575 mg ꢀ77%) of 12 as brown
crystals.
ꢀ
1
M.p.: 212±214 C; H NMR ꢀCDCl =DMSO-d , ꢁ, 300 MHz): 1.65 ꢀd, J 6.8 Hz, 6H, 2 CH ),
3
6
3
5
.88 ꢀsept, J 6.8 Hz, 1H, CH), 7.44 ꢀdd, J 8.1 Hz, J 4.7 Hz, 1H, pyridine-H), 7.65±7.81 ꢀm, 3H,
phenyl-H), 8.25 ꢀd, J 6.8 Hz, 2H, phenyl-H), 8.55 ꢀdd, J 4.7 Hz, J 1.5 Hz, 1H, pyridine-H),
1
3
8
.81 ꢀdd, J 8.1 Hz, J 1.5 Hz, 1H, pyridine-H), 9.36 ꢀs, 1H, imidazole-H) ppm; C NMR
ꢀ
CDCl =DMSO-d , ꢁ, 75 MHz): 19.2, 45.0, 117.1, 118.4, 120.6, 123.4, 124.5, 127.6, 129.2, 129.8,
3
6
1
32.8, 141.5, 146.8, 153.6, 164.1, 174.7 ppm; MS: m=z ꢀ%) 372 ꢀM , 9), 371 ꢀ16), 105 ꢀ100),
7
7 ꢀ76).
References
[1] Jacobsen EJ, Stelzer LS, Belonga KL, Carter DB, Im HK, Im WB, SethyVH, Tang AH,
VonVoigtlander PF, Petke JD ꢀ1996) J Med Chem 39: 3820
[2] Zi-Qiang Gu, Wong G, Dominguez C, de Costa BR, Rice KC, Skolnick P ꢀ1993) J Med Chem
3
6: 1001