Table 1 ¹H NMR (500 MHz, CDCl₃), δ_H in ppm

1

–

–

–

2

–

–

–

3

6.80, s

6.83, s

6.75, s

4

–

–

–

5

–

–

–

6

7.22 (d, J = 9.0 Hz)

7.20 (d, J = 8.3 Hz)

7.22 (d, J = 9.0 Hz)

7

7.46 (d, J = 9.0 Hz)

7.28 (d, J = 8.3 Hz)

7.48 (d, J = 9.0 Hz)

8

–

–

–

9

–

–

–

10

6.51, (d, J = 11.1 Hz)

6.48, (d, J = 11.0 Hz)

6.50, (d, J = 10.8 Hz) m

11

3.20, m

3.20, m

3.18, m

12

1.26, (d, J = 7.4 Hz)

1.28, (d, J = 7.1 Hz)

1.29, (d, J = 7.8 Hz)

13

1.26, (d, J = 7.4 Hz)

1.28, (d, J = 7.1 Hz)

1.29, (d, J = 7.8 Hz)

14

–

–

–

15

4.99, s

–

–

16

–

2.40, s

2.43, s

9-OCH₃

3.90, s

3.88, s

3.80, s

14-OCH₃

–

–

3.87, s