Table 3.

Hydrogen bond lengths (Å) and angles (°) in the optimized structures of the keto-oxime, keto-hydroxylamine and hydroxyl-oxime tautomers of molnupiravir, obtained by using the DFT/B3LYP/6-311++G(d,p) method.

Tautomer	D–X∙∙∙A	d(D–X)	d(X∙∙∙A)	d(D∙∙∙A)	∠(DXA)
keto-oxime	O2–H1∙∙∙O3	0.968	2.095	2.648	114.52
	O3–H2∙∙∙O4	0.974	1.843	2.718	147.92
	N2–H3∙∙∙O5	1.012	2.163	2.537	99.62
keto-hydroxylamine	O2–H1∙∙∙O3	0.967	2.165	2.676	111.59
	O3–H2∙∙∙O4	0.966	2.064	2.917	146.30
	O5–H4∙∙∙N2	0.975	2.032	2.622	116.97
hydroxyl-oxime	O2–H1∙∙∙O3	0.967	2.165	2.676	111.59
	O3–H2∙∙∙O4	0.966	2.064	2.917	146.30
	O5–H4∙∙∙N2	0.975	2.032	2.622	116.97