Table 1.

¹H and¹³C chemical shifts of compound 3 (experimental and theoretical values).

	Atoms	Exp.	Gas phase	DMSO
	C1	145.27	141.99	143.74
	C2	31.87	32.06	32.31
	C3	29.74	32.13	32.39
	C4	59.55	62.29	61.59
	C6	132.99	119.57	123.10
	C7	141.15	113.72	111.04
	C8	116.05	105.13	108.02
	H2	3.17	2.08	3.08
	H3	1.73	2.74	1.98
	H4	3.49	4.01	4.02
	H5	4.67	0.19	0.80
	H6	7.81	7.11	7.63