Table 1 NMR spectroscopic (400 MHz) data of compound 4 in DMSO- d ₆

2

-

161.51

qC

3

6.77 (s)

103.46

CH

C-4

C-4a,1^′,5^′

4

-

182.47

qC

5

-

162.97

qC

6

-

104.97

qC

7

-

156.36

qC

8

6.26 (s)

98.50

CH

C-8a

C-6, 2

4a

-

104.38

qC

8a

-

160.75

qC

1^′

-

121.98

qC

2^′

8.02 (d, J = 2.4, 8.4)

129.34

CH

C-5^′, 8a

3^′

6.88 (d, J = 8.4)

116.17

CH

C-1^′

4^′

-

151.42

qC

5^′

-

164.30

qC

6^′

6.91 (d, J = 2.4)

116.17

CH

C-1^′

C-3^′

1″

4.65 (d, J = 9.9)

73.74

CH

C-6, 2″

C-3″, 5″, 5, 7

2″

3.82 (dd, J = 9.2,9.6)

70.86

CH

C-1″

3″

3.24 (t, J = 9.2)

79.01

CH

4″

3.34 (t, J = 9.2)

71.18

CH

5″

3.22 (ddd, J = 5.0, 9.2)

82.22

CH

C-1″

6″

3.75 (d, J = 11.6)

61.65

CH₂

C-5″

3.52 (dd, J = 6.0,12.0)

1‴

3.17 s

48.97

CH₂

OCH₃

3.89

56.8

CH₃

C-4^′

OH-5

13.15