Table 1 The NMR data of compound 2c

1

161.70

2

104.15

3

165.67

4

90.09

6.43 (s, 1H)

90.09

157.54, 104.15, 109.21

4a

157.54

4b

156.21

5

117.76

7.40 (d, J = 8.4 Hz, 1H)

117.74

121.19, 124.27

6

135.07

7.68 (t, J = 7.9 Hz, 1H)

135.07

126.27, 156.21

7

124.27

7.35 (t, J = 7.5 Hz, 1H)

124.27

117.76, 121.19

8

126.27

8.24 (d, J = 7.9 Hz, 1H)

126.27

180.96, 135.07, 156.21

8a

121.19

9

180.96

8b

109.21

OCH₃

56.37

3.92 (s, 3H)

56.37

165.67

CH₂N

45.96

3.76 (s, 2H)

45.96

165.67, 161.70,

109.21, 54.24

1' and 4'

54.24

2.63 (brs, 4H)

54.24

23.81

2' and 3'

23.81

1.75 (brs, 4H)

23.81

23.81