Table 3.

¹³C NMR Chemical Shifts of Compounds 3–6^a

position	3	4	5	6
1	39.7	40.7	40.3	71.8
2	34.0	32.8	32.4	42.4
3	217.7	175.5	175.0	198.7
4	47.3	86.4	86.0	129.4
5	54.9	53.5	53.1	157.9
6	19.6	23.9	23.6	116.9
7	33.0	34.6	34.2	160.3
8	42.4	40.5	40.2	23.7
9	50.0	51.7	51.4	32.0
10	36.9	39.7	39.3	38.7
11	21.2	23.1	23.0	36.4
12	23.7	27.3	27.2	21.4
13	35.2	43.5	43.1	20.8
14	40.8	50.2	49.9	56.2
15	27.5	31.4	30.9	15.0
16	33.8	26.1	25.7
17	81.9	50.3	49.6
18	15.6	15.3	14.9
19	16.2	18.8	18.4
20	69.2	86.8	86.5
21	-	22.1	27.2
22	29.1	37.8	34.8
23	20.1	26.2	26.3
24	73.8	84.9	86.4
25	71.9	71.5	70.2
26	24.0	27.6	27.8
27	26.3	24.4	24.0
28	26.8	31.3	30.9
29	21.0	26.7	26.9
30	14.4	16.2	16.1

^aMeasured at 150 MHz and obtained in CDCl₃ with TMS as internal standard. Assignments supported with HSQC and HMBC NMR spectra.