Table 2.

¹³C NMR (ppm, mult) data of compounds 1–3 in acetone-d₆ (125 MHz).

Position	1	2	3
1	166.5, C	166.5, C	166.6, C
3	151.7, C	151.5, C	156.1, C
4	109.8, CH	109.7, CH	107.5, CH
4a	139.9, C	140.1, C	140.1, C
5	102.6, CH	102.9, CH	104.3, CH
6	167.9, C	166.4, C	164.6, C
7	101.6, CH	104.1, CH	103.0, CH
8	164.2, C	164.4, C	166.6, C
8a	100.9, C	100.1, C	100.3, C
9	41.2, CH2	41.2, CH2	73.1, CH
10	86.0, C	86.0, C	76.7, CH
11	37.4, CH2	37.4, CH2	76.1, CH
12	68.4, CH	68.4, CH
13	175.6, C	175.5, C
14	77.2, CH	77.2, CH
6-OCH3	56.3, CH3