4458
O.-S. Adetchessi et al. / Tetrahedron 61 (2005) 4453–4460
(200 MHz, CDCl3) d 1.72 (m, 4H, H-7 and H-8), 2.44 (t, 2H,
JZ5.50 Hz, H-6), 2.56 (t, 2H, JZ5.50 Hz, H-9), 4.27 (m,
4H, OCH2 and H-3), 5.19 (m, 1H, H-2), 6.85 (d, 2H, JZ
7.30 Hz, H-20 and H-60), 6.97 (t, 1H, JZ7.30 Hz, H-40),
7.26 (t, 2H, JZ7.30 Hz, H-30 and H-50); 13C NMR
(50 MHz, CDCl3) d 21.8 (C-8), 21.9 (C-7), 22.2 (C-9),
31.9 (C-6), 44.2 (C-3), 67.4 (OCH2), 75.8 (C-2), 114.3
(C-5a), 114.6 (C-20 and C-60), 1210.8 (C-40), 129.5 (C-30 and
C-50), 156.2 (C-9a), 157.7 (C-1 ), 161.1 (C-10a), 161.4
(CO); IR (KBr) 1680 cmK1 (C]O), 1635 cmK1 (C]N).
Anal. Calcd for C17H18N2O3: C, 68.44; H, 6.08; N, 9.39.
Found: C, 68.27; H, 6.07; N, 9.35.
and H-50); 13C NMR (50 MHz, DMSO-d6) d 20.9 (C-6),
27.8 (C-7), 29.8 (C-5), 46.0 (C-3), 67.7 (OCH2), 76.5 (C-2),
114.7 (C-20 and C-60), 117.4 (C-7a), 121.3 (C-40), 129.6
(C-30 and C-50), 151.0 (C-4a), 157.9 (C-10), 160.3 (C-9a),
169.2 (CO); IR (KBr) 1670 cmK1 (C]O), 1630 cmK1
(C]N). Anal. Calcd for C16H16N2O3: C, 67.59; H, 5.67; N,
9.85. Found: C, 67.40; H, 5.71; N, 9.83.
4.4.8.
6,7,8-Trihydro-2-phenoxymethyl-5H-cyclo-
penta[1,2-d]oxazolo[3,2-a]pyrimidin-5-one 4d. White
crystals (1.99 g, 35%); mp 146 8C (C2HCl3); 1H NMR
(200 MHz, CDCl3) d 2.05 (qt, 2H, JZ7.60 Hz, H-7), 2.71 (t,
2H, JZ7.60 Hz, H-6), 2.75 (t, 2H, JZ7.60 Hz, H-8), 4.18
(dd, 1H, JZ10.75, 4.00 Hz, H-3b), 4.30 (m, 3H, OCH2 and
H-3a), 5.26 (m, 1H, H-2), 6.84 (d, 2H, JZ7.70 Hz, H-20 and
H-60), 6.96 (t, 1H, JZ7.70 Hz, H-40), 7.26 (t, 2H, JZ
7.70 Hz, H-30 and H-50); 13C NMR (50 MHz, CDCl3) d 21.6
(C-7), 26.7 (C-6), 34.9 (C-8), 44.1 (C-3), 67.4 (OCH2), 76.5
(C-2), 114.06 (C-20 and C-60), 117.3 (C-5a), 121.9 (C-40),
129.5 (C-3 and C-50), 157.7 (C-8a), 158.8 (C-10), 159.4
(C-9a), 170.7 (CO); IR (KBr) 1680 cmK1 (C]O),
1640 cmK1 (C]N). Anal. Calcd for C16H16N2O3: C,
67.59; H, 5.67; N, 9.85. Found: C, 67.56; H, 5.88; N, 9.96.
4.4.3. 5,6,7,8-Tetrahydro-2-(4-ethylphenoxymethyl)-9H-
cyclohexa[1,2-e]oxazolo[3,2-a]pyrimidin-9-one 3b.
White crystals (2.28 g, 35%).
4.4.4. 6,7,8,9-Tetrahydro-2-(4-ethylphenoxymethyl)-5H-
cyclohexa[1,2-d]oxazolo[3,2-a]pyrimidin-5-one 4b.
White crystals (2.47 g, 38%); mp 104 8C (C2Cl4); 1H
NMR (200 MHz, CDCl3) d 1.17 (t, 3H, JZ7.55 Hz, CH3),
1.71 (m, 4H, H-7 and H-8), 2.29 (m, 2H, H-6), 2.55 (m, 2H,
H-9), 2.60 (q, 2H, JZ7.55 Hz, CH2), 4.17 (m, 2H, H-3),
4.28 (m, 2H, OCH2), 5.17 (m, 1H, H-2), 6.77 (d, 2H, JZ
8.30 Hz, H-20 and H-60), 7.07 (d, 2H, JZ8.30 Hz, H-30 and
H-50); 13C NMR (50 MHz, CDCl3) d 15.7 (CH3), 21.8 (C-8),
21.9 (C-7), 22.2 (CH2), 27.9 (C-9), 31.9 (C-6), 44.2 (C-3),
67.6 (OCH2), 75.8 (C-2), 114.4 (C-5a), 114.6 (C-20 and
C-60), 128.7 (C-30 and C-50), 137.7 (C-40), 155.8 (C-10),
156.2 (C-9a), 161.2 (C-10a), 161.4 (CO); IR (KBr) 1675
cmK1 (C]O), 1640 cmK1 (C]N). Anal. Calcd for
C19H22N2O3: C, 69.92; H, 6.79; N, 8.58. Found: C, 69.84;
H, 6.89; N, 8.62.
4.4.9. 5,6,7-Trihydro-2-(4-ethylphenoxymethyl)-8H-
cyclopenta[1,2-e]oxazolo[3,2-a]pyrimidin-8-one 3e.
1
White crystals (1.56 g, 25%); mp O260 8C (MeOH); H
NMR (200 MHz, DMSO-d6) d 1.15 (t, 3H, JZ7.55 Hz,
CH3), 2.01 (qt, 2H, JZ7.45 Hz, H-6), 2.51 (t, 2H, JZ
7.45 Hz, H-7), 2.56 (q, 2H, JZ7.55 Hz, CH2), 2.84 (t, 2H,
JZ7.45 Hz, H-5), 4.11 (dd, 1H, JZ10.0, 6.60 Hz, H-3b),
4.24 (m, 2H, OCH2b and H-3a), 4.40 (dd, 1H, JZ9.80,
8.90 Hz, OCH2a), 5.30 (m, 1H, H-2), 6.85 (d, 2H, JZ
8.55 Hz, H-20 and H-60), 7.12 (d, 2H, JZ8.55 Hz, H-30 and
H-50); 13C NMR (50 MHz, DMSO-d6) d 15.9(CH3), 20.9
(C-6), 27.3 (CH2),27.8 (C-7), 29.8 (C-5), 46.0 (C-3), 67.9
(OCH2), 76.6 (C-2), 114.6 (C-20 and C-60), 117.4 (C-7a),
128.7 (C-30 and C-50), 136.6 (C-40), 151.0 (C-4a), 156.0
(C-10), 160.3 (C-9a), 169.1 (CO); IR (KBr) 1665 cmK1
(C]O), 1630 cmK1 (C]N). Anal. Calcd for C18H20N2O3:
C, 69.21; H, 6.45; N, 8.97. Found: C, 69.45; H, 6.52; N,
8.93.
4.4.5. 5,6,7,8-Tetrahydro-2-(1-piperidinomethyl)-9H-
3c.
cyclohexa[1,2-e]oxazolo[3,2-a]pyrimidin-9-one
White crystals (1.73 g, 30%).
4.4.6. 6,7,8,9-Tetrahydro-2-(1-piperidinomethyl)-5H-
cyclohexa[1,2-d]oxazolo[3,2-a]pyrimidin-5-one 4c.
White crystals (2.25 g, 39%); mp 140 8C (C2Cl4); 1H
NMR (200 MHz, CDCl3) d 1.36 (m, 2H, CH2 pip.), 1.49
(m, 4H, CH2 pip.), 1.68 (m, 4H, H-7 and H-8), 2.44 (m, 8H,
NCH2, NCH2 pip. and H-6), 2.65 (t, 2H, JZ7.10 Hz, H-9),
3.99 (dd, 1H, JZ9.75, 7.40 Hz, H-3b), 4.23 (dd, 1H, JZ
9.75, 8.90 Hz, H-3a), 4.98 (m, 1H, H-2); 13C NMR
(50 MHz, CDCl3) d 21.7 (C-8), 21.9 (C-7), 22.2 (C-9),
23.8 (CH2 pip.), 25.9 (CH2 pip.), 31.8 (C-6), 46.0 (C-3),
55.3 (NCH2 pip.), 61.1 (NCH2), 77.0 (C-2), 114.1 (C-5a),
156.2 (C-9a), 156.4 (C-10a), 161.4 (CO); IR (KBr)
1680 cmK1 (C]O), 1635 cmK1 (C]N). Anal. Calcd for
C16H23N3O2: C, 66.41; H, 8.01; N, 14.52. Found: C, 66.37;
H, 7.97; N, 14.43.
4.4.10. 6,7,8-Trihydro-2-(4-ethylphenoxymethyl)-5H-
cyclopenta[1,2-d]oxazolo[3,2-a]pyrimidin-5-one 4e.
White crystals (2.49 g, 40%); mp 115 8C (C2HCl3); 1H
NMR (200 MHz, CDCl3) d 1.13 (t, 3H, JZ7.55 Hz, CH3),
2.06 (qt, 2H, JZ7.50 Hz, H-7), 2.59 (q, 2H, JZ7.55 Hz,
CH2), 2.71 (t, 2H, JZ7.50 Hz, H-6), 2.75 (t, 2H, JZ
7.50 Hz, H-8), 4.16 (dd, 1H, JZ10.75, 4.00 Hz, H-3b), 4.32
(m, 3H, OCH2 and H-3a), 5.25 (m, 1H, H-2), 6.78 (d, 2H,
JZ8.80 Hz, H-20 and H-60), 7.07 (d, 2H, JZ8.80 Hz, H-30
and H-50); 13C NMR (50 MHz, CDCl3) d 15.7 (CH3), 21.6
(C-7), 26.7 (CH2), 27.9 (C-6), 34.9 (C-8), 44.1 (C-3), 67.6
(OCH2), 76.6 (C-2), 114.6 (C-20 and C-60), 117.2 (C-5a),
128.8 (C-30 and C-50), 137.7 (C-40), 155.8 (C-8a), 158.8
(C-10), 159.4 (C-9a), 170.7 (CO); IR (KBr) 1680 cmK1
(C]O), 1635 cmK1 (C]N). Anal. Calcd for C18H20N2O3:
C, 69.21; H, 6.45; N, 8.97. Found: C, 69.39; H, 6.58; N,
9.03.
4.4.7. 5,6,7-Trihydro-2-phenoxymethyl-8H-cyclo-
penta[1,2-e]oxazolo[3,2-a]pyrimidin-8-one 3d. White
1
crystals (1.25 g, 22%); mp O260 8C (MeOH); H NMR
(200 MHz, DMSO-d6) d 2.02 (qt, 2H, JZ7.45 Hz, H-6),
2.52 (t, 2H, JZ7.45 Hz, H-7), 2.86 (t, 2H, JZ7.45 Hz,
H-7), 4.13 (dd, 1H, JZ9.90, 6.60 Hz, H-3b), 4.29 (m, 2H,
OCH2b and H-3a), 4.40 (dd, 1H, JZ9.75, 8.90 Hz, OCH2a),
5.32 (m, 1H, H-2), 6.93 (d, 2H, JZ7.80 Hz, H-20 and H-60),
6.97 (t, 1H, JZ7.80 Hz, H-40), 7.31 (t, 2H, JZ7.80 Hz, H-30
4.4.11. 5,6,7-Trihydro-2-(piperidinomethyl)-8H-cyclo-
penta[1,2-e]oxazolo[3,2-a]pyrimidin-8-one 3f. White