Table 1.

¹H and ¹³C NMR data of compounds 2–5 (500/125 MHz).

	2		3		4		5
	1H	13C	1H	13C	1H	13C	1H	13C
1		198.6 s		194.9 s		194.9 s		198.0 s
2		106.2 s		105.7 s		105.7 s		104.2 s
3		171.9 s		166.7 s		167.8 s		169.0 s
4	4.54 brt 5.0	66.4 d	4.28 brt 5.0	65.8 d	4.26 t 5.0	65.7 d	4.55 t 5.5	65.4 d
5	1.90 m	37.4 t	2.30 m	34.5 t	1.96 m	34.4 t	2.12 m	38.2 t
	2.64 m		2.41 m		2.40 m		2.28 m
6	3.88 dd 5.0, 3.0	79.5 d	3.75 dd, 5.0, 3.0	79.2 d	3.73 dd 5.0, 3.0	79.2 d	4.09 dd 5.5, 3.0	69.4 d
7	3.53 s	58.5 q	3.47 s	58.4 q	3.50 s	58.5 q
8	2.28 m	18.6 t	2.35 m	16.3 t	2.31 m	16.2 t	2.26 m	16.4 t
			2.19 m
9	2.46 m	42.8 d	2.12 m	43.8 d	2.06 m	43.5 d	1.96 m	43.3 d
10		89.6 s		87.6 s		87.5 s		89.0 s
11	1.36 s	22.4 q	1.35 s	22.4 q	1.36 s	22.2 q	1.35 s	23.1 q
12	1.90 m	38.7 t	1.88 m	37.3 t	2.00 m	37.7 t	1.89 m	37.6 t
	2.22 m		2.15 m		2.25 m		2.15 m
13	1.82 m	26.1 t	2.06 m	28.4 t	1.84 m	26.9 t	1.59 m	26.9 t
	2.20 m		1.57 m		2.30 m		1.95 m
14	2.68 m	55.4 d	2.27 m	44.8 d	2.37 m	51.4 d	2.16 m	49.1 d
15		212.0 s		149.7 s		150.2 s		145.3 s
16			4.88 s	109.9 t	1.85 s	14.4 q	4.74 s	111.5 t
			5.10 s				4.63 s
17	2.16, s	29.2 q	4.11 d 1.5	65.3 d	5.94 d 10.0	124.7 d	1.67 s	19.2 q
18					7.41 dd 15.0, 10.0	138.8 d
19					6.09 d 15.0	129.3 d
20						198.7 s
21					2.27 s	27.7 q