Table 2.

Comparison of ¹H and ¹³C-NMR resonances in caffeine (1) with 6-selenocaffeine (2).

Carbon	Caffeine (1)		6-Selenocaffeine (2)
	1H-NMR a	13C-NMR a	1H-NMR a	13C-NMR a
	δ (ppm)	δ (ppm)	δ (ppm)	δ (ppm)
2	---	150.9	---	149.1
4	---	148.0	---	143.8
5	---	106.5	---	121.2
6	---	154.4	---	175.8
8	7.97	142.7	8.35	147.4
10	3.12	27.4	3.75	37.4
11	3.36	29.3	c.a. 3.38	30.3
12	3.84	33.1	4.10	35.8

^a The spectra were recorded in DMSO-d₆ at room temperature.