Table 1 NMR spectroscopic data for compound 1a and 1b.

1

81.5 (d)

3.35 (1H, dd, 5.5, 9.5)

1

81.5 (d)

3.36 (1H, dd, 5.4, 10.9)

2

30.5 (t)

1.88 (1H, overlapped)

1.62 (1H, m)

2

30.8 (t)

1.99 (1H, overlapped)

1.72 (1H, m)

3

39.3 (t)

1.49 (1H, overlapped)

1.28 (1H, dt, 4.3, 9.5)

3

39.1 (t)

1.46 (1H, overlapped)

1.32 (1H, dt, 4.1, 9.6)

4

33.0 (s)

−

4

33.0 (s)

−

5

52.4 (d)

0.98 (1H, dd, 1.7, 10.7)

5

51.7 (d)

1.11 (1H, dd, 2.0, 12.0)

6

28.3 (t)

2.00 (1H, q, 12.5)

1.88 (1H, overlapped)

6

25.4 (t)

1.99 (2H, overlapped)

7

73.7 (d)

5.12 (1H, m)

7

76.4 (d)

5.37 (1H, dd, 4.5, 11.8)

8

61.5 (s)

−

8

61.0 (s)

−

9

56.4 (d)

1.83 (1H, d, 8.4)

9

55.5 (d)

1.77 (1H, d, 8.5)

10

45.8 (s)

−

10

45.8 (s)

−

11

19.6 (t)

2.89 (1H, dd, 5.2, 10.8)

1.49(1H, overlapped)

11

19.5 (t)

2.86 (1H, dd, 5.1, 11.9)

1.46 (1H, overlapped)

12

31.8 (t)

2.13 (1H, m)

1.73 (1H, m)

12

31.8 (t)

1.84 (1H, dt, 3.8, 12.3)

1.66 (1H, m)

13

44.1 (d)

3.09 (1H, br.s)

13

44.1 (d)

3.09 (1H, br.s)

14

78.2 (d)

6.00 (1H, br.s)

14

75.0 (d)

4.80 (1H, br.s)

15

207.0 (s)

−

15

205.9 (s)

−

16

146.3 (s)

−

16

146.9 (s)

−

17

117.9 (t)

6.15 (1H, s) 5.38 (1H, s)

17

116.5 (t)

6.14 (1H, s) 5.42 (1H, s)

18

33.3 (q)

0.88 (3H, s)

18

33.0 (q)

0.91 (3H, s)

19

21.3 (q)

0.81 (3H, s)

19

21.3 (q)

0.81 (3H, s)

20

63.9 (t)

4.60 (1H, d, 13.6)

4.54 (1H, d, 13.6)

20

64.1 (t)

4.57 (1H, d, 13.4)

4.43 (1H, d, 13.4)

20-OAc

171.3 (s)

−

20-OAc

170.7 (s)

−

20-OAc

21.5 (q)

2.16 (3H, s)

20-OAc

21.6 (q)

2.17 (3H, s)

14-OAc

170.2 (s)

−

7-OAc

168.3 (s)

−

14-OAc

21.6 (q)

1.99 (3H, s)

7-OAc

21.3 (q)

2.00 (3H, s)

7-OH

−

2.45 (1H, d, 6.6)

14-OH

−

3.97 (1H, s)

1-OH

−

1.39 (1H, d, 5.5)

1-OH

−

1.41 (1H, d, 5.4)