1350
BENITES, PREITE, AND CORTES
Table 1. IR and H NMR Chemical Shifts (CDCl3, 200.13 MHz)
1
Compound IR (cmÀ1
)
1H NMR (ꢀ, ppm)
1
1707
2.67–2.50 (m, 1H, H-8a), 2.24–2.16 (m, 1H, H-8b),
2.15–1.98 (m, 1H, H-7a), 1.79–1.06 (m, 10H), 1.14
(s, 3H, 10-Me), 0.92 (s, 3H, 4-Me-(), 0.88 (s, 3H, 4-Me-)
3
1741, 1237 4.26 (dd, J¼5.2, 11.3 Hz, 1H, H-11a), 4.12 (t, J=10.8 Hz,
1H, H-12a), 4.07–4.00 (m, 2H, H-11b(H-12b), 2.19–2.13
(m, 1H, H-8), 2.02 (s, 3H, AcO), 2.01 (s, 3H, AcO), 1.91–
1.75 (m, 1H) 1.72–0.90 (m, 11H), 0.83 (s, 3H, 4-Me-b),
0.81 (s, 3H, 10-Me), 0.78 (s, 3H, 4-Me-b).
5
6
3356, 2993, 4.24–3.97 (m, 4H, H11(H12), 2.71 (bs, 2H, 2ꢁOH), 2.26–
1452, 978
2.20 (m, 2H, H-7), 1.89–l.09 (m, 9H), 0.98 (s, 3H, 10-Me),
0.90 (s, 3H, 4-Me-b), 0.84 (s, 3H, 4-Me-b)
3320, 1036, 4.05 (dd, J¼4.6, 11.7, 1H, H-11), 3.70–3.35 (m, 5H, H-
914, 903
11bþH12 þ 2 ꢁOH), 2.16–1.10 (m, 11H), 1.09 (s, 3H,
10-Me), 0.81
(s, 3H, 4-Me-(), 0.78 (s, 3H, 4-Me-b)
7
8
3440, 1063 4.06 (bs, 1H, OH) 3 73–3.43 (m, 4H, H-11(H-12). 3.23
(bs, 1H, OH), 3.00 (bs, 1H, OH), 1.93–1.11 (m, 12H), 0.88
(s, 3H, 10-Me), 0.87 (s, 3H, 4-Me-a), 0.82 (s, 3H, 4-Me-b)
3443, 1699, (CDCl3þD2O) 3.65 (dd, J¼7.1, 11.5 Hz, 1H,H-12), 3.52
1461, 1058 (dd, J¼3.9, 11.5 Hz, 1H, H-12), 2.87–272 (m, 11H, H-8),
2.06–1.08 (m, 11H), 1.13 (s, 3H, 10-Me), 0.90
(s, 3H, 4-Me-b), 0.86 (s, 3H,4-Me-a)
3331, 1016 3.97–3.54 (m, 4H, H-11(H-12), 2.18–0.92 (m, 15H),
9
0.86 (s, 3H, 4-Me-a), 0.85 (s, 3H, 10-Me), 0.80
(s, 3H, 4-Me-b)
For analytical TLC, Merck silica gel 60 in 0.25 mm layer was used.
Chromatographic separations were carried out by conventional column
on Merck silica gel 60 (230–400 Mesh) using hexane-EtOAc gradients of
increasing polarity.
All reactions were routinely run under a N2 atmosphere. All organic
extracts were dried over anhydrous magnesium sulfate and evaporated
under reduced pressure, at a temperature below 65ꢀC.
(þ)-Confertifolin (4) was obtained from an hexane extract of the bark
13
of D. winteri
.
8,9-Drimen-11,12-diol (5)
To a suspension of LiAlH4 (0.4 g, 10.5 mmol) in dry THF (20 mL) was
added dropwise a solution of confertifolin (1.0 g, 4.2 mmol) solution in THF