Table 3.

¹³C NMR Spectroscopic Data of Compounds 1–3 [δ_c, ppm]^a

carbon	1	2	3
C-1	54.4	61.6	61.8
C-3	37.4	44.1b	44.1b
C-4	29.1	22.5	23.1
C-4a	125.7	124.9	129.5
C-5	105.1	105.0	105.8
C-6	146.8	146.6	152.3
C-7	133.6	133.9	137.1
C-8	141.1	141.9	148.2
C-8a	123.2	122.6	121.6
C-α	38.4	39.6	39.3
C-9	134.5	135.5	135.7
C-10	115.4	115.0	115.0
C-11	149.9	149.4	149.4
C-12	147.4	147.2	147.3
C-13	111.4	111.6	111.7
C-14	122.2	123.0	123.1.
C-1′	65.2	65.2	65.2
C-3′	51.2	51.1	51.4
C-4′	24.2	24.1	24.2
C-4a′	122.3	122.2	122.0
C-5′	132.9	133.1	132.5
C-6′	137.7	138.1	138.8
C-7′	151.1	151.1	151.2
C-8′	105.7	106.1	106.3
C-8a′	146.5	147.0	147.4
C-α′	40.8	41.0	41.2
C-9′	134.5	134.1	134.1
C-10′	131.1	131.0	131.1
C-11′	120.3	120.0	119.9
C-12′	153.4	153.9	153.9
C-13′	120.3	120.0	120.0
C-14′	133.0	132.9	132.7
N-Me	-	42.6	42.8
6-OMe	56.3	56.3	56.0
7-OMe	-	-	56.5
12-OMe	56.2	56.3	56.2
N′-Me	44.1	44.1b	44.1b
6′-OMe	60.6	60.8	60.6
7′-OMe	56.2	56.2	56.5

^aRecorded in CDCl₃ at 100 MHz and 300 K

^bOverlapped signals