Table 1 NMR data for compound 1 in CDCl₃

1

1.33 (1H, m)

2.06 (1H, dd, J = 13.6, 4.4 Hz)

C₂, C₁₀, C₁₄

2

1.60 (2H, m)

3

1.96 (1H, m)

2.35 (1H, m)

C₂, C₄, C₁₅

C₄

4

5

2.38 (1H, m)

C₁₀

6

2.31 (1H, m)

2.67 (1H, dq, J = 12.8, 2.8 Hz)

C₇, C₁₀

C₇, C_8, C₁₀

7

8

4.98 (1H, d, J = 2.0 Hz)

9

3.88 (1H, d, J = 3.6 Hz)

C₅, C₇, C₈

10

11

12

13

1.83 (3H, t, J = 1.6 Hz)

C₇, C₁₁, C₁₂

14

0.89 (3H, s)

C₁, C₅, C₉, C₁₀

15

4.88 (1H, d, J = 1.6 Hz)

4.60 (1H, d, J = 1.6 Hz)

C₃, C₅