Table 1.

¹H and ¹³C NMR (CDCl₃, 300.13 MHz and 75.4 MHz) and HMBC assignment for 1.

Position	δC, Type	δH, (J in Hz)	COSY	ROESY	HMBC
1α	37.1, CH2	1.81, m
β		2.18, m
2α	33.8, CH2	2.50,m	H-1
β		2.64, dd (17.9, 7.2)	H-1
3	199.5, CO	-
4	129.2, CH	6.66, d (0.8)	-		C-2, 3, 5
5	155.0, C	-
6	195.9, CO	-
7	56.1, CH	3.20, s	-	H-9, 14, 15	C-5, 6, 8, 14
8	66.2, C	-
9	43.9, CH	1.90, m
10	36.8, C	-
11	20.7, CH2	1.85, m
12	39.0, CH2	1.21, m; 1.40, m
13	44.3, C	-
14	51.8, CH	1.94, m
15	18.7, CH2	1.25, m
16	27.7, CH2	1.34, m; 1.75, m
17	56.0, CH	1.30, m
18	12.4, CH3	0.89, s			C-12, 13, 14, 17
19	21.8, CH3	1.50, s	-	1β, 2β	C-1, 5, 9
20	40.0, CH	2.04, m
21	21.0 CH3	1.04, d (6.8)	H-20		C-17, 20, 22
22	135.0, CH	5.15, dd (15.3, 7.3)	H-20, 23		C-21, 24
23	132.5, CH	5.25, dd (15.3, 8.0)	H-22, 24		C-20, 24, 25, 26
24	42.8, CH	1.85, m			C-22, 23
25	33.0, CH	1.48, m
26	17.6, CH3	0.92, d (6.8)	H-24		C-23, 24, 25
27	20.0, CH3	0.82, d (6.8)	H-25		C-24, 25, 28
28	19.6 CH3	0.84, d (6.8)	H-25		C-24, 25, 27