Table 2.

Intermolecular hydrogen interaction between UCK2 protein and its inhibitors.

UCK2	HB with CTP	HB with FKB	HB with APN
Active Residues	(BD ≤ 3.5 Å, DHA ≥ 90°)	(BD ≤ 3.5 Å, DHA ≥ 90°)	(BD ≤ 3.5 Å, DHA ≥ 90°)
Thr29	Hβ with 3′O	Oγ1 with 2 H	Hα with 3 O
Ala30	Hα with Oγ3, HN with Oα2		HN with 3 O
Gly32	HN with Oγ2
Lys33	Hζ2 with Oγ2, HN with Oγ2, Hζ1 with Oα1, Hζ1 with Oβ3	Hζ2 with 4 O	Hζ1 with 5 O
Ser31	HN with Oγ2
Ser34	HN with Oγ1, Hα with Oβ1, Hβ2 with Oγ1	Oγ with 4′ H
Asp62			HN with 7 O
Tyr65		Hη with 9′ O	Hη with 10 O
Phe83
Asp84	Oγ1 with 2′O, Oγ2 with 3′O
Tyr112	Oη with 4N
His117	Nδ1 with 4N
Glu135		Oε1 with 10′ H, 4′ H	Oε1 with 5 H
		O with 10′ H	O with 7 H
Arg166	Oη12 with 3′O, Oη22 with 2′O, Oη22 with 3′O
Arg169	Hη22 with Oγ2	Hη22 with 2 O	Hη12 with 3O
Arg174	Oη11 with 4′O
Arg179

HB: hydrogen bond, BD: bond distance, DHA: D, hydrogen donor; H, hydrogen; A, hydrogen acceptor.