In this work, we report in-depth computational studies of three plausible tautomeric forms, generated through the migration of two acidic protons of the N⁴-hydroxylcytosine fragment, of molnupiravir, which is emerging as an efficient drug to treat COVID-19. The DFT calculations were performed to verify the structure of these tautomers, as well as their electronic and optical properties. Molecular docking was applied to examine the influence of the structures of the keto-oxime, keto-hydroxylamine and hydroxyl-oxime tautomers on a series of the SARS-CoV-2 proteins. These tautomers exhibited the best affinity behavior (−9.90, −7.90, and −9.30 kcal/mol, respectively) towards RdRp-RTR and Nonstructural protein 3 (nsp3_range 207–379-MES).

A new variable-rate coding technique is presented for two-dimensional (2-D) constraints. For certain constraints, such as the (0, 2)-runlength-limited (RLL) and (3,¿)-RLL constraints, the technique is shown to improve on previously published lower bounds on the capacity of the constraint.

We received a complaint from the Université Catholique de Louvain

Nearly tight lower and upper bounds on the capacity of generalized Ising channels are presented. For the case where feedback is allowed, a closed-form expression for the capacity is found for channel error probability p ∈ [0, p0], where p0 ≈ 0.398324. A near-capacity-achieving family of encoders is presented for the values p ∈ [0, p0]. Two lower bounds on that capacity for larger values of p are presented, one of which is tight on the interval [p0, 0.5].

A compound 2-(6,8-dibromo-3-(4-hydroxycyclohexyl)-1,2,3,4-tetrahydroquinazolin-2-yl)phenol was synthetised from ambroxol hydrochloride and salicylaldehyde. The structure of the compound was studied with UV, IR, Raman, and ¹H NMR spectroscopy. The inhibitory ability of the synthetised compound on the corrosion of mild stainless steel EN Fe37-3FN in 0.5M hydrochloric acid solution was studied using gravimetric and electrochemical methods, including potentiodynamic polarisation and EIS. It was shown that the inhibitory activity of the compound increases with the increase of its concentration in a solution. An addition of 3mg/l of the compound reduces the corrosion rate by 20 and that of 400mg/l by 85. The data of gravimetric and electrochemical measurements coincide well. The sorption of the compound on the metal surface obeys the Langmuir adsorption isotherm, and the nature of adsorption is physical. The compound exhibits the chelating activity with both ferrous and ferric ions in the acidic solution. The synthetised compound may be a good choice for the inhibition of steel corrosion in acidic environments.