3.3.1.2 3C-like main protease (3CLpro)
3CLprotease (which is the main protease (Mpro)) or nsp5 directly
mediates the processing of the viral polyprotein and maturation of viral
nonstructural proteins (nsps), which are essential in the life cycle of
the virus. Initiation of viral RNA synthesis and switching translation
to RNA replication are other functions of this protein. 3CLpro is among
the most attractive target for anti-coronavirus drug development. Based
on a computational drug repurposing study performed by Junmei Wang
(Wang, 2020), five drugs, namely, Carfilzomib, Eravacycline, Valrubicin,
Lopinavir and Elbasvir, are identified to have inhibitory activities on
3Cl pro of 2019-nCoV. According to another computational study performed
by Nguyen et al., Bortezomib, Flurazepam, Ponatinib, Sorafenib,
Dasatinib, are five potent potential inhibitors of 3CL pro for 2019-nCoV
(Nguyen et al., 2020).
Due to the similar active-site architecture of the 3C protease in
coronaviruses and enteroviruses, Zhang et al designed peptidomimetic
α-ketoamides as suitable targets for the development of broad-spectrum
antiviral drugs. They introduced a compound (11r) expecting to exhibit
excellent antiviral activity against 2019-nCoV (Li and De Clercq, 2020;
Zhang et al., 2020b)