Synthetic Studies Directed towards Agelasine Analogs
(150 MHz, [D6]DMSO): δ = 160.9 (C-2), 156.3 (C-6), 153.3 (C-4),
9H-purin-6-amine (4i): The products were prepared from purine 2i
141.3 (C-8), 114.7 (C-5), 61.1 (COCH3), 54.1 (NOCH3), 36.5 [N-9- (0.147 g, 0.73 mmol) as described for compounds 3a and 4a above.
CH3], 29.3 (N6-CH3) ppm. 15N NMR (60 MHz, [D6]DMSO): δ =
–137 (N-7), –214 (N6), –230 (N-9) ppm. N-1 and N-3 were not
observed. MS (EI): m/z (%) = 223 (63) [M]+, 193 (45), 192 (100),
164 (27), 163 (27), 149 (71), 148 (39). HRMS (EI): calcd. for
C9H13N5O2 223.1069; found 223.1071.
The crude product was purified twice by flash chromatography
(Combiflash, 0–10% MeOH in CH2Cl2). 3i: Yield 0.149 g (56%),
pale yellow solid, m.p. 252 °C (dec.). 1H NMR (600 MHz, [D6]-
DMSO): δ = 10.44 (s, 1 H, NH), 9.26 (s, 1 H, H-8), 7.46–7.45 (s, 2
H, Ph), 7.41–7.38 (s, 2 H, Ph), 7.37–7.34 (s, 1 H, Ph), 7.16 (q, J =
4.7 Hz, 1 H, NHCH3), 5.51 (s, 2 H, CH2), 3.79 (s, 3 H, OCH3),
3.69 (s, 3 H, NCH3), 2.82 (d, J = 4.7 Hz, 3 H, NHCH3) ppm. 13C
NMR (150 MHz, [D6]DMSO): δ = 153.3 (C-2), 144.2 (C-4), 137.1
(C-6), 135.4 (C-8), 134.6 (C-1 in Ph), 128.7 (CH in Ph), 128.5 (CH
in Ph), 128.3 (CH in Ph), 102.4 (C-5), 61.6 (OCH3), 51.7 (CH2),
31.1 (NCH3), 27.4 (NHCH3) ppm. MS (ESI): m/z (%) = 299 (100),
[M]+. HRMS (ESI): calcd. for C15H19N6O 299.1620, found
299.1630. 4i: Yield 0.046 g (22%), yellow sticky solid. 1H NMR
(300 MHz, [D6]DMSO): δ = 7.78 (s, 1 H, H-8), 7.35–7.22 (m, 5 H,
Ph), 6.57 (q, J = 4.7 Hz, 1 H, NHCH3), 5.22 (s, 2 H, CH2), 3.73
(s, 3 H, OCH3), 3.58 (s, 3 H, NCH3), 2.79 (d, J = 4.7 Hz, 3 H,
NHCH3) ppm. 13C NMR (75 MHz, [D6]DMSO): δ = 159.3 (C-2),
155.4 (C-6), 153.8 (C-4), 139.0 (C-8), 137.6 (C-1 in Ph), 128.4 (CH
in Ph), 128.1 (CH in Ph), 127.0 (CH in Ph), 112.2 (C-5), 61.6
(OCH3), 52.5 (CH2), 29.0 (NCH3), 28.2 (NHCH3) ppm. MS (EI):
m/z (%) = 298 (39) [M]+, 268 (92), 267 (100), 163 (30), 162 (22), 91
(28). HRMS (EI): calcd. for C15H18N6O 298.1542; found 298.1547.
7-Benzyl-2-ethoxy-6-(methoxyamino)-9-methyl-7H-purinium Bro-
mide (3g) and N-Benzyl-2-ethoxy-N-methoxy-9-methyl-9H-purin-6-
amine (4g): The products were prepared from purine 2g (0.163 g,
0.73 mmol) as described for compounds 3a and 4a above. The
products were separated by flash chromatography (2ϫ20 cm silica
column, 3–10% MeOH in CH2Cl2, followed by 5–10% saturated
NH3 in MeOH in CH2Cl2). 3g: Yield 0.150 g (52%), off-white solid,
m.p. 170–171 °C. 1H NMR (600 MHz, [D6]DMSO): δ = 11.75 (br.,
1 H, NH), 9.42 (s, 1 H, H-8), 7.46–7.36 (m, 5 H, Ph), 5.58 (s, 2 H,
CH2), 4.40 (q, J = 7.1 Hz, 2 H, CH2), 3.76 (s, 3 H, CH3), 3.75 (s,
3 H, CH3), 1.31 (t, J = 7.1 Hz, 3 H, CH2CH3) ppm. 13C NMR
(75 MHz, [D6]DMSO): δ = 156.8 (C-2), 142.3 (C-4), 137.0 (C-8),
136.8 (C-6), 134.5 (C in Ph), 128.7 (CH in Ph), 128.6 (CH in Ph),
128.3 (CH in Ph), 106.0 (C-5), 64.7 (OCH2), 61.7 (OCH3), 51.8
(NCH2), 31.5 (NCH3), 13.9 (CH2CH3) ppm. MS (ESI): m/z (%) =
314.1 (100) [M – HBr]+. HRMS (EI): calcd. for C16H20N5O2
314.1617, found 314.1617. C16BrH21N5O2 (385.3): C 48.62, H 5.35,
N 17.72; found C 48.60, H 5.13, N 17.69. 4g: Yield 0.046 g (20%),
1
purple solid, m.p. 122–124 °C. H NMR (300 MHz, [D6]DMSO):
Acknowledgments
δ = 8.02 (s, 1 H, H-8), 7.34–7.24 (m, 5 H, Ph), 5.26 (s, 2 H, CH2),
4.29 (q, J = 7.0 Hz, 2 H, CH2), 3.76 (s, 3 H, OCH3), 3.65 (s, 3 H,
NCH3), 1.28 (t, J = 7.0 Hz, 3 H, CH2CH3) ppm. 13C NMR
(75 MHz, [D6]DMSO): δ = 160.4 (C-2), 155.4 (C-6), 153.4 (C-4),
141.3 (C-8), 137.1 (C in Ph), 128.2 (CH in Ph), 128.1 (CH in Ph),
127.2 (CH in Ph), 114.1 (C-5), 62.3 (OCH2), 61.7 (OCH3), 52.2
(NCH2), 29.2 (NCH3), 14.4 (CH2CH3) ppm. MS (EI): m/z (%) =
313 (41) [M]+, 283 (100), 282 (64), 255 (30), 254 (9), 149 (42), 106
(40), 91 (52). HRMS (EI): calcd. for C16H19N5O2 313.1539; found
313.1532.
The Norwegian Research Council is greatly acknowledged for a
scholarship to H. R. (grant 171323/V30), and for financing of the
Bruker Avance DPX200, DPX 300, and DRX500 as well as the
Bruker AVII600 instruments used in this study. Faculty of Mathe-
matics and Science, University of Oslo is acknowledged for financ-
ing the Bruker AV600 instrument.
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7-Benzyl-2-(dimethylamino)-6-(methoxyamino)-9-methyl-7H-purin-
ium Bromide (3h) and N-Benzyl-2-(dimethylamino)-N-methoxy-9-
methyl-9H-purin-6-amine (4h): The products were prepared from
purine 2h (0.163 g, 0.73 mmol) as described for compounds 3a and
4a above. The crude product was purified twice by flash chromatog-
raphy (Combiflash, 0–10% MeOH in CH2Cl2). 3h: Yield 0.178 g
(61 %), pale yellow solid, m.p. 79–82 °C. 1H NMR (300 MHz,
CD2Cl2): δ = 10.52 (s, 1 H, H-8), 8.32 (s, 1 H, NH), 7.68–7.65 (m,
2 H, Ph), 7.39–7.32 (m, 3 H, Ph), 5.66 (s, 2 H, CH2), 3.93 (s, 3 H,
OCH3), 3.83 (s, 3 H, NCH3), 3.14 [s, 6 H, N(CH3)2] ppm. 13C
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Yield 0.016 g (7%), yellow wax. 1H NMR (600 MHz, [D6]DMSO):
δ = 7.81 (s, 1 H, H-8), 7.35–7.34 (m, 2 H, Ph), 7.30–7.27 (m, 2 H,
Ph), 7.24–7.23 (m, 1 H, Ph), 5.20 (s, 2 H, CH2), 3.76 (s, 3 H,
OCH3), 3.59 (s, 3 H, NCH3), 3.09 [s, 6 H, N(CH3)2] ppm. 13C
NMR (150 MHz, [D6]DMSO): δ = 158.5 (C-2), 154.9 (C-6), 153.9
(C-4), 139.4 (C-8), 137.6 (C-1 in Ph), 128.3 (CH in Ph), 128.1 (CH
in Ph), 127.1 (CH in Ph), 111.7 (C-5), 61.6 (OCH3), 52.6 (CH2),
36.9 [N(CH3)2], 28.9 (NCH3) ppm. MS (EI): m/z (%) = 312 (47)
[M]+, 282 (49), 284 (100), 91 (22). HRMS (EI): calcd. for
C16H20N6O 312.1699; found 312.1705.
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Eur. J. Org. Chem. 2008, 5099–5106
© 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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