Molecules 2008, 13
210
1
(62 mg; 43%, 2 steps). H NMR (400 MHz, CDCl3) δ: 8.06 (d, J = 9.2 Hz, 2H), 7.82 (br s, 1H), 7.34
(d, J = 9.2, 2H), 6.74 (s, 1H), 6.65 (s, 1H), 2.52 (s, 2H), 2.32 (s, 3H), 2.36 (s, 3H), 2.23 (s, 3H), 1.72
13
ppm (s, 6H). C NMR (400 MHz, CDCl3) δ: 173.2, 170.3, 150.4, 144.3, 143.2, 139.4, 137.6, 133.4,
132.9, 125.0, 123.6, 118.6, 51.3, 40.8, 32.5, 25.7, 22.1, 20.3 ppm. HRMS (EI): m/z 405.1577 [M+Na]+
([C21H24N2O5Na] = 405.1578).
Acknowledgements
We are grateful to S. S. Chandran, E. L. Myers, and R. F. Turcotte for contributive discussions.
This work was supported by Grant CA073808 (NIH). L.D.L. was supported by Biotechnology
Training Grant 08349 (NIH) and an ACS Division of Organic Chemistry Graduate Fellowship
sponsored by the Genentech Foundation. NMRFAM was supported by Grant P41RR02301 (NIH). The
BIF was established with Grants BIR-9512577 (NSF) and RR13790 (NIH).
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