Table 5.

Hydrogen bonds between A6–A9 and B5–B6 in insulin and its analogs

Bonding atoms	INS	DPI	DHI	DesB1–B2DPI	DHPI(1)	DHPI(2)
CysA6O–LeuB6N	2.78	2.80	2.85	3.00	2.92	2.84
CysA7O–HisB5ND1	2.83	2.87	2.48	2.91	2.67	2.86
SerA9O–HisB5ND1	3.03	2.86	2.70	3.08	3.58	2.94

Values represent the distances in Å. The molecules adopt the same names as in Table 4. Des(B1–B2)DPI, dis(B1–B2) despenthapeptide (B26–B30) insulin; INS, 2Zn insulin.