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J. SU ET AL.
Compound 2d. Pale yellow solid, mp 53–54ꢁC (lit.[24] mp 52–54ꢁC); 1H NMR
(300 MHz, CDCl3): d 0.95 (t, 6H, J ¼ 7.2 Hz), 2.57 (s, 6H), 4.01 (q, 4H, J ¼ 7.2 Hz),
7.16 (d, 2H, J ¼ 8.4 Hz), 7.35 (d, 2H, J ¼ 8.4 Hz); MS (EI, 70 ev): m=z (%) 407 (31.3,
[M]þ), 362 (100), 334 (72), 289 (49), 77 (13).
1
Compund 2e. Pale yellow solid, mp 66–67ꢁC (lit.[22] mp 65–67ꢁC); H NMR
(300 MHz, CDCl3): d 0.93 (t, 6H, J ¼ 7.2 Hz), 2.57 (s, 6H), 4.00 (q, 4H, J ¼ 7.2 Hz),
7.16 (d, 2H, J ¼ 8.4 Hz), 7.35 (d, 2H, J ¼ 8.4 Hz); MS (EI, 70 ev): m=z (%) 361 (100,
[M]þ), 316 (74), 288 (50), 270 (66), 139 (72), 84 (59), 77 (7).
Compound 2f. Colorless solid, mp 50–52ꢁC (lit.[1] mp 50ꢁC); 1H NMR
(300 MHz, CDCl3): d 0.95 (t, 6H, J ¼ 7.2 Hz), 2.55 (s, 6H), 3.78 (q, 3H), 4.01 (d,
4H, J ¼ 7.2 Hz), 6.86 (d, 2H, J ¼ 9.0 Hz), 7.10 (d, 2H, J ¼ 9.0 Hz); MS (EI, 70 ev):
m=z (%) 357 (100, [M]þ), 312 (21), 282 (20), 266 (11), 255 (9), 135 (18), 105 (14), 77 (27).
Compound 2g. Pale yellow solid, mp 61–63ꢁC (lit.[23] mp 61–63ꢁC); 1H NMR
(300 MHz, CDCl3): d 0.98 (t, 6H, J ¼ 7.2 Hz), 2.62 (s, 6H), 4.04 (q, 4H, J ¼ 7.2 Hz),
7.57–7.59 (m, 2H), 8.18–8.27 (m, 2H); MS (EI, 70 ev): m=z (%) 372 (48.8, [M]þ), 355
(29.5), 327 (100), 299 (39.5), 281 (32.5), 139 (23.2).
1
Compund 2h. Pale yellow solid, mp 163–164ꢁC (lit.[25] mp 162–163ꢁC); H
NMR (300 MHz, CDCl3): d 1.27 (t, 6H, J ¼ 7.2 Hz), 2.56 (s, 6H), 4.32 (q, 4H,
J ¼ 7.2 Hz), 6.79 (d, 1H, J ¼ 16.5 Hz), 7.10 (d, 2H, J ¼ 16.5 Hz), 7.26–7.42 (m, 5H);
MS (EI, 70 ev): m=z (%) 353 (78, [M]þ), 308 (26), 278 (100), 263 (17), 250 (21),
234 (41), 165 (44), 152 (24), 105 (19), 77 (19).
1
Compund 2i. Yellow oil (lit.[1] oil); H NMR (300 MHz, CDCl3): d 1.15 (t,
6H, J ¼ 7.2 Hz), 2.51 (s, 6H), 4.21 (q, 4H, J ¼ 7.2 Hz), 6.42 (d, 1H, J ¼ 3.3 Hz),
6.54 (d, 1H, J ¼ 3.3 Hz), 7.42 (s, 1H); MS (EI, 70 ev): m=z (%) 317 (71.5, [M]þ),
272 (52.3), 243 (38.1), 214 (100), 95 (45.3).
ACKNOWLEDGMENT
The authors are grateful to Southwest University of China for financial support.
REFERENCES
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