Table 2.

¹³C NMR data (chemical shifts in ppm) for 11a–d (125 MHz, C₆D₆).

carbon	11a	11b	11c	11d
C-1	7.7	7.7	7.8	7.8
C-2	36.1	36.2	34.6	34.9
C-3	215.0	215.6	215.4	214.5
C-4	48.8	47.7	47.3	48.2
C-5	75.8	78.4	74.6	74.7
C-6	37.0	38.1	37.3	37.5
C-7	27.1	23.6	25.4	26.2
C-8	12.0	11.8	9.3	11.2
4-Me	12.4	14.7	11.3	11.4
6-Me	13.9	16.3	15.0	14.5