Notes
Journal of Natural Products, 2007, Vol. 70, No. 9 1509
mixture was refluxed for 6 h, allowed to cool to RT, and quenched
with 10 mL of ammonium hydroxide. It was then extracted with DCM/
water [3 × 20 mL (1:1)] The organic layers were combined, dried over
sodium sulfate, and evaporated. The residue was chromatographed over
silica using hexane/EtOAc (3:1). Evaporation of the organic fractions
provided 0.138 g (82%) of 7 as a yellow oil: Rf 0.34 in hexanes/EtOAc
calcd for C21H22O5 ·0.4H2O, C 69.75%, H 6.36%, found C 69.90%,
H 6.32%; HRMS calc [M+ + Na] 377.1365, found 377.1354.
Acknowledgment. We are grateful to the U.S. Department of
Agriculture and the Southern Regional Research Center (New Orleans)
for their financial support of this research.
1
(5:1); H NMR (600 MHz, CDCl3) δ 6.54 (s, 1H, Ar-H), 5.21 (s, 2H,
O-CH2-O), 5.13 (t, 1H, J ) 6.6 Hz, CHd), 4.90 (s, 2H, O-CH2-O),
3.78 (s, 3H, OCH3), 3.47 (s, 6H, 2 × OCH3) 3.30 (d, 2 H, J ) 6.6 Hz,
Supporting Information Available: Copies of proton and carbon
NMR spectra for all compounds. This material is available free of
CH2), 2.49 (s, 3H, COCH3), 1.76 (s, 3H, CH3), 1.65 (s, 3H, CH3); 13
C
NMR (100 MHz, CDCl3) δ 201.9,157.5, 155.8, 153.5, 131.2, 123.1,
120.2, 117.1, 101.1, 94.7, 94.3, 57.4, 56.1, 32.6, 25.7, 23.3, 17.8; HRMS
calc [M+ + Na] 361.1627, found 361.1628.
References and Notes
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1
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NP070158Y