Table 1.

Comparison of experimental and calculated ¹³C NMR data of ring B in 1.

C	1 a (exp)	1a b	1b b
1	149.1	147.3	151.6
2	140.3	148.8 c	148.8 c
3	120.0	116.6	112.3 c
4	116.0	118.7	126.3 c
5	131.2	128.5	128.5
6	117.1	116.6	109.0 c

^a Taken from 2D spectra referenced to CDCl₃ (δ_C 77.16) at 125 MHz; ^b Calculated values [25]; ^c Bold values indicate ∆δ_C > 5.