Binding of Coumarin 334 with β-Cyclodextrin and with C-Hexylpyrogallol[4]arene: Opposite Fluorescence Behavior

Table 3

¹H NMR spectral data of β-CD, C334, and C-HPA.

𝛽-CD		C334			C-HPA
Position of protons	Chemical shift, 𝛿 (ppm)	Nature of protons	Position of protons	Chemical shift, 𝛿 (ppm)	Nature of protons	Chemical shift, 𝛿 (ppm)
H3	3.30	Methyl protons	21	2.62	C-Hexyl chain
H4	3.33	Chromone proton	4-CH	8.35	Methyl protons	0.93
H2	3.56	Aromatic proton	17-CH	7.24	Methylene protons	1.28–1.45
H6	3.60	Methylene protons	9 and 13	1.90	CH in the linked pyrogallol units	2.21–2.28
H5	3.64	Methylene protons	8 and 14	2.69
Primary hydroxyl	4.46	Methylene protons	10 and 12	3.33	Aromatic ring
H1	4.83				Aromatic protons	7.49
Secondary hydroxyl	5.68 and 5.74				Hydroxyl protons	6.86, 6.90, and 8.80