Table 1.

¹H NMR spectroscopic data for compounds 1–6 in acetone-d₆ (δ in ppm, J in Hz)

No	1 a	2 c	3 a	4 b	5 a	6 c
3	6.17, d (1.8)	6.17, d (2.3)	6.21, s	6.25, d (2.1)	6.12, br. s	6.17, s
5	6.25, d (1.8)	6.25, d (2.3)	6.22, s	6.12, d (2.1)	6.03, br. s	6.25, s
7	2.15, s	2.15, s	2.20, s	2.11, s	2.11, s	2.15, s
8	3.26, d (6.7)	3.26, d (6.7)	2.82, dd (14.4, 2.2)	2.79, dd (16.1, 5.9)	3.06, dd (15.3, 7.9)	3.27*
			2.68, dd (14.4, 9.3)	2.45, dd (16.1, 8.5)	2.93, dd (15.3, 9.5)
9	5.09, t (6.7)	5.09, t (6.7)	4.28, dd (9.3, 2.2)	3.85, td (8.5, 5.8)	4.62, dd (9.5, 7.9)	5.11*
11	1.90–2.00, m	1.97–1.99, m	2.22–2.25*	1.66–1.75, m	1.50–1.56, m	2.25, t (9.9)
			2.14–2.17, m
						1.96–2.03*
12	2.03–2.11, m	2.07–2.10, m	2.22–2.25*	2.14–2.24, m	2.09–2.20, m	1.69–1.74, m
						1.33–1.40, m
13	5.12, t (6.6)	5.14, t (7.0)	5.20, br. s	5.17, t (7.2)	5.18, t (6.9)	3.29*
15	1.90–2.00, m	2.21–2.26, m	1.98, t (7.5)	1.97, t (7.6)	1.98, t (7.5)	1.54–1.58, m
		1.94–1.97, m				1.33–1.40, m
16	1.54–1.58, m	1.62–1.68, m	2.07–2.09*	2.06–2.08*	2.06–2.09*	2.09–2.13, m
		1.28–1.35, m				2.03–2.05, m
17	3.97, m	3.24, td (5.3, 1.8)	5.10*	5.10, t (6.9)	5.10, t (7.0)	5.11*1
19	1.68, s	1.11, s	1.59, s	1.58, s	1.59, s	1.58, s
20	4.89, br. s	1.11, s	1.65, s	1.65, s	1.65, s	1.64, s
	4.74, br. s
21	1.58, s	1.58, s	1.63, s	1.61, s	1.63, s	1.07, s
22	1.75, s	1.75, s	5.11, br. s	1.16, s	1.20, s	1.76, s
			4.84, br. s
4-OH	7.86, s	7.88, s	8.01, s	7.89, s	8.05, s	7.89, s
6-OH	8.02, s	8.06, s	8.56, s			8.05, s
9-OH			4.88, d (2.8)	4.14, d (5.6)
10-OH					3.54, s
13-OH						3.56, d (5.8)
14-OH						3.20, s
17-OH	3.73, d (4.2)	3.54, d (5.3)
18-OH		3.40, s

^aMeasured at 400 MHz

^bMeasured at 500 MHz

^cMeasured at 600 MHz

* Signals were overlapped