Table 1.

Comparative ¹³C NMR data (CDCl₃, 175 ^† and 150 ^‡ MHz) reported by McPhail and co-workers [18] for naturally-occurring 16; by Willwacher et al. [20,21] for synthetic 12a, 12b and 16; and by Xu, Ye and co-workers [19] for synthetic 12a and 16.

Carbon	Naturally-Occurring 16 [18] †	Synthetic 12a [21] ‡	Synthetic 12b [21] ‡	Synthetic 12a [19] ‡	Synthetic 16 [19] ‡	Synthetic 16 [20] ‡
1	167.4	167.3	166.8	167.1	167.4	167.4
2	123.1	123.1	123.6	122.9	123.0	123.1
3	147.1	146.3	146.1	146.2	147.2	147.1
4	38.8	38.5	39.5	38.2	38.8	38.8
5	73.9	73.4	73.9	73.2	73.9	73.9
6	37.6	36.7	38.2	36.4	37.6	37.6
7	73.1	72.8	72.7	72.6	73.1	73.1
8	39.7	39.3	39.2	39.0	39.7	39.7
9	72.5	73.1	73.2	72.9	72.5	72.5
10	43.1	42.9	43.5	42.6	43.1	43.1
11	34.2	32.8	34.1	32.6	34.2	34.2
12	141.5	140.9	141.3	140.6	141.6	141.5
13	123.9	123.8	124.9	123.6	123.9	123.9
14	131.3	130.5	130.6	130.3	131.3	131.3
15	126.9	126.5	126.2	126.3	127.0	126.9
16	31.1	31.2	31.0	31.0	31.1	31.1
17	81.0	81.3	81.8	81.1	81.0	81.0
18	37.3	37.1	36.9	36.9	37.4	37.4
19	36.8	36.0	36.4	35.8	36.8	36.8
20	83.2	82.7	82.1	82.5	83.2	83.2
21	73.0	73.4	73.3	72.3	73.0	73.1
22	34.1	34.1	34.7	33.9	34.1	34.1
23	72.3	72.5	74.0	72.3	72.3	72.3
24	66.1	65.7	65.7	65.6	66.1	66.1
25	18.3	20.1	22.0	19.9	18.3	18.3
26	14.5	14.7	14.9	14.6	14.6	14.5
1′	94.2	94.0	94.1	93.7	94.2	94.2
2′	80.8	80.9	80.9	80.6	80.8	80.8
3′	71.7	71.7	71.6	71.4	71.7	71.7
4′	74.3	74.2	74.2	74.0	74.3	74.3
5′	68.1	68.2	68.2	67.9	68.1	68.1
6′	17.7	17.7	17.7	17.5	17.7	17.7
7′	59.1	59.2	59.1	59.0	59.2	59.1