Table 3.

Selected torsion angles (°) of local minima for Ac-l-Ala-[psi](Imz)⁻-4-Me (4) optimized at M06-2X/6–311++G(d,p) method, their relative energies (ΔE) and the relative energy difference between tautomers (ΔEτ/π) in kcal/mol, and population (p)

Ac-l-Ala-[psi](Imz)−-4-Me (4)
Conformer	φ	ψ	E [a.u.]	ΔE	p [%]
Gas Phase
C5	− 165.3	178.1	− 551.5603	0.00	58.67
β2	− 165.2	− 3.4	− 551.5600	0.21	41.33
Chloroform
β2	− 162.1	− 5.4	− 551.6351	0.00	50.46
C5	− 162.1	176.8	− 551.6353	0.01	49.54
Water
C5	− 160.7	153.1	− 551.6555	0.00	51.87
β2	− 161.3	− 33.7	− 551.6555	0.06	46.86
αLπ	56.0	50.1	− 551.6512	2.57	0.69
αDτ	56.3	− 128.1	− 551.6510	2.68	0.58