Table 3. ¹H, ¹³C, HMBC and COSY NMR spectroscopic data (500 MHz, DMSO-d₆) of compounds 2, 4, 6 and 8.

Position	Compound 2				Compound 4		Compound 6			Compound 8
	δ1H	δ13C	HMBC	COSY	δ1H	δ13C	δ1H	δ13C	COSY	δ1H	δ13C	COSY
2		156.97				156.83		156.90			164.41
3		134.70				133.71		134.67		6.78 s	102.94
4		178.20				178.01		178.21			182.54
5	12.63 s	161.77	C5, C6, C10		12.62 s	161.69	12.66 s	161.76		13.17 s	156.48
6	6.21 d (1.6)	99.19	C8, C10, C5,C7	H8	6.21 d (1.9)	99.17	6.21 br s	99.14	H8	6.27 s	98.67
7	10.86 s	164.68				164.63		164.66		10.83 s	162.91
8	6.42 d (1.6)	94.21	C6, C10, C9,C7	H6	6.44 d (1.9)	94.14	6.40 br s	94.08	H6	6.78 s	105.26
9		157.70				156.85		157.76			160.89
10		104.62				104.43		104.54			104.55
1′		121.00				121.34		121.18			122.11
2′	7.77 dd (8.58)	131.06	C6′, C2, C4′	H3′	8.07 d (8.8)	131.45	7.30 d (1.5)	115.91		8.02 d (8.7)	129.39	H3′
3′	6.93 dd (8.58)	115.87	C5′, C1′, C4′	H2′	6.87 d (8.8)	115.53		148.90		6.91 d (8.7)	116.32	H2′
4′	10.2 s	160.46				160.43		145.67		10.35 s	161.61
5′	6.93 dd (5.58)	115.87	C3′, C1′, C4′	H6′	6.87 d (8.8)	115.53	6.88 d (8.4)	116.10	H6′	6.91 d (8.7)	116.32	H6′
6′	7.77 dd (8.58)	131.06	C2′, C2, C4′	H5′	8.07 d (8.8)	131.45	7.25 d (8.4)	121.57	H5′	8.02 d (8.7)	129.39	H5′
3′- OCH3							3.19 s	49.06
1″	5.31 d (1.8)	102.27	C3, C2″	H2″	5.40 d (7.5)	102.14	5.26 s	102.29	H2″	4.70 d (9.8)	73.88	H2″
2″	3.99 dd (3.6, 1.5)	70.55		H1″, H3″		71.68	3.98 dd	70.51	H1″, H3″	3.85 dd	71.39
3″	3.48 dd	71.08		H2″, H4″		73.57	3.50 dd	71.05	H2″, H4″	3.29 dd	79.18
4″	3.15 dd	71.61		H3″		68.35	3.17 dd	71.63	H3″	3.52 dd	71.09
5″	3.17 dd	70.83		H6″		76.25	3.23 dd	70.80	H6″	3.26 dd	82.29
6″	0.81 d (6.09)	17.93		H5″		60.67	0.82 d (6.0)	17.96	H5″	3.76 dd	61.82

Assignments were done by 1D (¹H, ¹³C, DEPT) and 2D (COSY, HSQC, HMBC) NMR experiments.