3916
G. Mroß et al. / Tetrahedron 65 (2009) 3910–3917
3.4.2. 1,2,3-Trimethylxanth-9-one (8b)
d
¼2.26 (s, 3H, CH3), 2.42 (s, 3H, CH3), 2.88 (s, 3H, CH3), 7.13 (s, 1H,
Starting with 7b (0.180 g, 0.63 mmol), 8b was isolated (0.125 g,
CH, Ar), 7.34 (d, 3J¼8.9 Hz, 1H, CH, Ar), 7.56 (d, 3J¼8.9 Hz, 1H, CH,
83%) as a colourless solid, mp¼124–126 ꢁC. 1H NMR (300 MHz,
Ar), 8.22 (d, 4J¼2.6 Hz, 1H, CH, Ar). 13C NMR (250 MHz, CDCl3):
CDCl3):
d
¼2.27 (s, 3H, CH3), 2.42 (s, 3H, CH3), 2.91 (s, 3H, CH3), 7.15
d
¼16.2, 17.7, 21.8 (CH3), 116.2 (CH, Ar), 117.9 (C, Ar), 118.9 (CH, Ar),
(s, 1H, CH, Ar), 7.28–7.40 (m, 2H, CH, Ar), 7.61–7.68 (m, 1H, CH, Ar),
123.9 (C, Ar),126.1 (CH, Ar),128.9,132.3 (C, Ar),133.9 (CH, Ar),139.4,
8.27 (d, 3J¼8.0 Hz, 1H, CH, Ar). 13C NMR (250 MHz, CDCl3):
d¼15.2,
144.6,153.3, 155.3 (C, Ar),177.6 (C]O). IR (neat, cmꢀ1):
n
¼3094 (w),
~
17.7, 21.8 (CH3), 116.2, 117.1 (CH, Ar), 118.3 (C, Ar), 123.2, 126.8 (CH,
3071 (w), 3030 (w), 2958 (w), 2921 (w), 2852 (w), 2730 (w), 1644
(s), 1599 (s), 1557 (m), 1470 (m), 1455 (s), 1429 (s), 1373 (m), 1326
(m), 1276 (s), 1265 (s), 1224 (m), 1184 (m), 1130 (m), 1057 (m), 1045
(m),1006 (m). MS (EI, 70 eV): m/z (%)¼274 (Mþ, 37Cl, (34)), 272 (Mþ,
35Cl, (100)), 271 (23), 257 (53). HRMS (EI): calcd for C16H13O2Cl
(Mþ): 272.0598, found: 272.0598.
Ar), 129.4, 131.9 (C, Ar), 133.8 (CH, Ar), 139.3, 144.2, 155.0, 155.5 (C,
Ar), 178.9 (C]O). IR (neat, cmꢀ1):
n
¼3282 (w), 3072 (w), 3044 (w),
~
2970 (w), 2946 (w), 2917 (w), 2859 (w), 2726 (w), 1726 (w), 1644
(s), 1599 (s), 1462 (s), 1454 (s), 1410 (s), 1371 (s), 1340 (m), 1326 (m),
1297 (s), 1267 (s), 1229 (m), 1214 (m), 1202 (m), 1187 (m), 1187 (m),
1148 (m), 1118 (m), 1109 (m), 1083 (m), 1048 (s), 1023 (s), 1003 (s).
MS (EI, 70 eV): m/z (%)¼238 (Mþ, (100)), 223 (64). HRMS (EI): calcd
for C16H14O2 (Mþ): 238.0988, found: 238.0986.
3.4.7. 1-Methoxy-3-methylfluoren-9-one (5)
Starting with 3e (0.151 g, 0.58 mmol), 5 was isolated (0.120 g,
90%) as a yellow solid, mp¼130 ꢁC. 1H NMR (300 MHz, CDCl3):
3.4.3. 1-Methyl-3-phenylxanth-9-one (8c)
d 2.40 (s, 3H, CH3), 3.96 (s, 3H, OCH3), 6.62 (s,1H, CH, Ar), 6.95 (s,1H,
Starting with 7c (0.110 g, 0.33 mmol), 8c was isolated (0.083 g,
CH, Ar), 7.24–7.48 (m, 3H, CH, Ar), 7.63 (d, 3J¼7.2 Hz, 1H, CH, Ar). 13
C
88%) as a yellow solid, mp¼106–108 ꢁC. 1H NMR (300 MHz,
NMR (250 MHz, CDCl3):
d¼22.4 (CH3), 55.7 (OCH3), 113.3, 114.0 (CH,
CDCl3):
d
¼2.43 (s, 3H, CH3), 6.92 (s, 1H, CH, Ar), 7.21–7.41 (m, 8H,
Ar), 117.8 (C, Ar), 119.9, 123.6, 129.0, 133.5 (CH, Ar), 135.0, 143.0,
CH, Ar), 7.53–7.63 (m, 1H, CH, Ar), 8.11 (d, 3J¼8.2 Hz, 1H, CH, Ar).
146.5, 148.3,158.2 (C, Ar),191.4 (C]O). IR (neat, cmꢀ1):
n
¼3040 (w),
~
13C NMR (250 MHz, CDCl3):
(CH, Ar), 122.7 (C, Ar), 123.6, 126.8, 126.9, 127.5, 128.3, 128.7, 134.2
d¼21.7 (CH3), 114.2 (C, Ar), 117.3, 117.4
3006 (w), 2969 (w), 2940 (w), 2846 (w), 1730 (w), 1693 (s), 1600 (s),
1581 (s), 1485 (m), 1454 (s), 1415 (s), 1377 (m), 1334 (m), 1303 (s),
1275 (s), 1239 (s), 1185 (s), 1172 (s), 1155 (m), 1131 (s), 1087 (m),
1038 (s), 1011 (m). MS (EI, 70 eV): m/z (%)¼224 (Mþ, (86)), 209 (24),
195 (100), 181 (21), 166 (18), 165 (96), 152 (33). HRMS (EI): calcd for
C15H12O2 (Mþ): 224.0831, found: 224.0831.
(CH, Ar), 141.9, 143.9, 144.7, 155.3, 157.3 (C, Ar), 176.6 (C]O). IR
(neat, cmꢀ1):
n
¼3316 (w), 3103 (w), 3075 (m), 3058 (m), 3023
~
(m), 2951 (m), 2920 (m), 2851 (m), 1660 (s), 1603 (s), 1563 (s),
1537 (m), 1494 (m), 1469 (s), 1462 (s), 1440 (s), 1402 (m), 1351 (s),
1335 (m), 1324 (m), 1306 (s), 1297 (s), 1229 (s), 1215 (m), 1173 (m),
1142 (m), 1114 (m), 1103 (m), 1070 (m), 1029 (m), 1013 (m). MS (EI,
70 eV): m/z (%)¼285 (Mþ, (100)). HRMS (EI): calcd for C20H14O2
(Mþ): 285.0910, found: 285.0906.
References and notes
1. (a) Lee, H. J.; Lee, J. H.; Hwang, B. Y.; Kim, H. S.; Lee, J. J. J. Antibiot. 2002, 55, 552;
(b) Hargreaves, J.; Park, J.-o.; Ghisalberti, E. L.; Sivasithamparam, K.; Skelton, B.
W.; White, A. H. J. Nat. Prod. 2002, 65, 7.
3.4.4. 1,2,3,7-Tetramethylxanth-9-one (8d)
Starting with 7e (0.120 g, 0.42 mmol), 8d was isolated (0.101 g,
2. Hussein, S. A. M.; Ayoub, N. A.; Nawwar, M. A. M. Phytochemistry 2003, 63, 905.
3. Nawwar, M. A. M.; Hussein, S. A. M.; Buddrus, J.; Linscheid, M. Phytochemistry
1994, 35, 1349.
4. Fiedler, P.; Gambaro, V.; Garbarino, J. A.; Quilhot, W. Phytochemistry 1986, 25,
461.
5. Lee, S.-H.; Tanaka, T.; Nonaka, G.-I.; Nishioka, I. Chem. Pharm. Bull. 1991, 39, 630.
6. Yoshida, T.; Ahmed, A. F.; Okuda, T. Chem. Pharm. Bull. 1993, 41, 672.
7. Elix, J. A.; Jones, A. J.; Lajide, L.; Coppins, B. J.; James, P. W. Aust. J. Chem. 1984, 37,
2349.
8. (a) Mayer, W. Justus Liebigs Ann. Chem. 1952, 578, 34; (b) Noyce, D. S.; Weldon, J.
W. J. Am. Chem. Soc. 1952, 74, 5144; (c) Jackson, W. T.; Boyd, R. J.; Froelich, L. L.;
Gapinski, D. M.; Mallett, B. E.; Sawyer, J. S. J. Med. Chem. 1993, 36, 1726; (d)
Hellwinkel, D.; Bohnet, S. Chem. Ber. 1987, 120, 1151; (e) Hormi, O. E. O.; Hir-
velae, L. Tetrahedron Lett. 1993, 34, 6463; (f) Hernandez, J. V.; Muniz, F. M.; Oliva,
A. I.; Simon, L.; Perez, E.; Moran, J. R. Tetrahedron Lett. 2003, 44, 6983; (g) Si-
mon, L.; Muniz, F. M.; Saez, S.; Raposo, C.; Sanz, F.; Moran, J. R. Helv. Chim. Acta
2005, 88, 1682.
9. See for example: (a) Fujimoto, H.; Satoh, Y.; Yamaguchi, K.; Yamazaki, M. Chem.
Pharm. Bull. 1998, 46, 1506; (b) Noro, T.; Ueno, A.; Mizutani, M.; Hashimoto, T.;
Miyase, T. Chem. Pharm. Bull. 1984, 32, 4455; (c) Hong, D.; Yin, F.; Hu, L.-H.; Lu, P.
Phytochemistry 2004, 65, 2595; (d) Tanaka, N.; Takaishi, Y. Phytochemistry 2006,
67, 2146; (e) Iinuma, M.; Tosa, H.; Toriyama, N.; Tanaka, T.; Ito, T.; Chelladurai, V.
Phytochemistry 2006, 43, 681; (f) Hirakawa, K.; Yoshida, M.; Oikawa, S.; Ka-
wanishi, S. Photochem. Photobiol. 2003, 77, 349.
10. Liu, Y.; Zou, L.; Ma, L.; Chen, W.-H.; Wang, B.; Xu, Z.-L. Bioorg. Med. Chem. 2006,
14, 5683.
11. Pedro, M.; Cerqueira, F.; Sousa, M. E.; Nascimento, M. S. J.; Pinto, M. Bioorg. Med.
Chem. 2002, 10, 3725.
95%) as a yellow solid, mp¼143–145 ꢁC. 1H NMR (300 MHz, CDCl3):
d
2.27 (s, 3H, CH3), 2.41 (s, 3H, CH3), 2.44 (s, 3H, CH3), 2.91 (s, 3H,
CH3), 7.14 (s, 1H, CH, Ar), 7.29 (d, 3J¼8.5 Hz, 1H, CH, Ar), 7.45 (d,
3J¼8.2 Hz, 1H, CH, Ar), 8.06 (d, 4J¼1.4 Hz, 1H, CH, Ar). 13C NMR
(250 MHz, CDCl3):
d
¼15.2, 17.8, 20.8, 21.8 (CH3), 116.2, 116.9 (CH,
Ar), 118.3, 122.7 (C, Ar), 126.1 (CH, Ar), 131.6, 132.8 (C, Ar), 135.0 (CH,
Ar), 139.3, 144.0, 153.2, 155.5 (C, Ar), 179.0 (C]O). IR (neat, cmꢀ1):
~
n
¼3027 (w), 2920 (w), 2859 (w), 2738 (w), 1644 (s), 1604 (s), 1592
(s), 1557 (m), 1489 (s), 1456 (s), 1428 (s), 1375 (m), 1329 (m), 1288
(s), 1268 (m), 1228 (s), 1268 (m), 1228 (s), 1195 (m), 1154 (m), 1136
(m), 1078 (w), 1047 (w), 1005 (w). MS (EI, 70 eV): m/z (%)¼252 (Mþ,
(100)), 251 (29), 237 (55). HRMS (EI): calcd for C17H16O2 (Mþ):
252.1144, found: 252.1147.
3.4.5. 3,7-Dimethyl-1-phenylxanth-9-one (8e)
Starting with 7f (0.030 g, 0.09 mmol), 8e was isolated (0.025 g,
93%) as a yellow solid, mp¼117–119 ꢁC. 1H NMR (300 MHz, CDCl3):
d
¼2.32 (s, 3H, CH3), 2.42 (s, 3H, CH3), 6.90 (s, 1H, CH, Ar), 7.30–7.50
(m, 8H, CH, Ar), 7.95 (s, 1H, CH, Ar). 13C NMR (250 MHz, CDCl3):
d
¼20.7, 21.7 (CH3), 116.9 (C, Ar), 117.1, 117.4 (CH, Ar), 122.3 (C, Ar),
126.2, 126.9, 127.5, 128.3, 128.5 (CH, Ar), 133.3 (C, Ar), 135.4 (CH, Ar),
12. Larcher, G.; Morel, C.; Tronchin, G.; Landreau, A.; Seraphin, D.; Richomme, P.;
Bouchara, J.-P. Planta Med. 2004, 70, 569.
141.9, 143.8, 144.5, 153.5, 157.3 (C, Ar), 176.7 (C]O). IR (neat, cmꢀ1):
13. Verhoog, N. J. D.; Joubert, E.; Louw, A. J. Agric. Food Chem. 2007, 55, 4371.
14. (a) Deachathai, S.; Mahabusarakam, W.; Phongpaichit, S.; Taylor, W. C. Phyto-
chemistry 2005, 66, 2368; (b) Panthong, K.; Pongcharoen, W.; Phongpaichit, S.;
Taylor, W. C. Phytochemistry 2006, 67, 999; (c) Hein, S. M.; Gloer, J. B.; Koster, B.;
Malloch, D. J. Nat. Prod. 1998, 61, 1566.
15. Madan, B.; Singh, I.; Kumar, A.; Prasad, A. K.; Raj, H. G.; Parmar, V. S.; Ghosh, B.
Bioorg. Med. Chem. 2002, 10, 3431.
16. Maia, F.; Almeida, M. d. R.; Gales, L.; Kijjoa, A.; Pinto, M. M. M.; Saraiva, M. J.;
Damas, A. M. Biochem. Pharmacol. 2005, 70, 1861.
~
n
¼3303 (w), 3079 (w), 3056 (w), 3028 (w), 2922 (w), 2854 (w),
1655 (s), 1608 (s), 1563 (m), 1482 (s), 1468 (s), 1441 (s), 1423 (s),
1402 (m), 1343 (s), 1288 (s), 1231 (m), 1218 (m), 1201 (m), 1168 (m),
1132 (m), 1121 (s), 1071 (m), 1029 (w), 1012 (w). MS (EI, 70 eV): m/z
(%)¼300 (Mþ, (38)), 299 (100). HRMS (EI): calcd for C21H15O2 (Mþ):
299.1066, found: 299.1069.
17. Gnerre, C.; Thull, U.; Gaillard, P.; Carrupt, P.-A.; Testa, B.; Fernandes, E.; Silva, F.;
Pinto, M.; Pinto, M. M. M.; Wolfender, J.-L.; Hostettmann, K.; Cruciani, G. Helv.
Chim. Acta 2001, 84, 552.
3.4.6. 7-Chloro-1,2,3-trimethylxanth-9-one (8f)
Starting with 7g (0.065 g, 0.21 mmol), 8f was isolated (0.056 g,
96%) as a yellow solid, mp¼164–166 ꢁC. 1H NMR (300 MHz, CDCl3):
18. Li, J.-C.; Feng, L.; Sun, B.-H.; Ikeda, T.; Nohara, T. Biol. Pharm. Bull. 2005, 28, 534.