NMR data of compound 1^a.

Position	1a		1b
	δ C, type	δ H (J in Hz)	δ C, type	δ H (J in Hz)
1/1′	179.5, C		179.5, C
2/2′	159.0, C		159.0, C
3/3′	121.2, C		121.2, C
4/4′	188.3, C		188.3, C
5/5′	145.4, C		145.4, C
6/6′	139.8, C		139.8, C
7/7′	152.8, C		152.8, C
8/8′	102.5, CH	7.17, s	102.5, CH	7.17, s
9/9′	127.2, C		127.2, C
10/10′	112.5, C		112.5, C
11	120.4, C		120.4, C
12	43.5, CH2	3.03, s	43.5, CH2	3.03, s
13	169.9, C		169.9, C
14	24.8, CH3	1.88, s	24.8, CH3	1.88, s
15	61.6, CH3	4.10, s	61.6, CH3	4.09, s
11′	120.1, C		120.1, C
12′	43.3, CH2	3.08, s	43.3, CH2	3.08, s
13′	168.5, C		168.5, C
14′	25.1, CH3	1.86, s	25.1, CH3	1.86, s
15′	61.6, CH3	4.09, s	61.6, CH3	4.09, s
16′	52.5, CH3	3.68, s	52.5, CH3	3.68, s

^aMeasured in CDCl₃–CD₃OD (2 : 1) (¹H at 600 MHz and ¹³C at 150 MHz).