Table 3.

The list of 10 compounds selected for secondary assays, to estimate their efficacy to inhibit PRRSV at doses of 0.1, 1 and 8 μM concentration.

No.	Compound	Known pharmacological action
1	Bufalin	Cardiac glycoside with antiviral activity (Cui et al., 2010).
2	Catechin hydrate, (+)-	Flavonoid, anti-oxidant, cyclo-oxygenase inhibitor, anti inflammatory (Kuzuhara et al., 2009).
3	Cepharanthine	An alkaloid with antiviral activity against SARS CoV; anti-inflammatory, inhibits lipooxygenase (Baba et al., 2001, Zhang et al., 2005).
4	Coumermycin A1	Novobiocin related antibiotic with antiviral activity (Palù et al., 1986).
5	Cryptotanshinone	A herb derived tanshinone that blocks Signal transducer and activator of transcription 3 (STAT3) dimerization and inhibits cytokine production by immune cells (Kang et al., 2000, Shin et al., 2009).
6	Cyclopiazonic acid	A fungal metabolite that acts on endoplasmic reticulum resident Ca2+ ATPase and mediates activation of NFkB, a key component of immune cell signaling (Xia et al., 2006).
7	12-Deoxyphorbol 13-phenylacetate 20-acetate	A phorbol ester that activates PKCβ, and mimics IFN mediated signaling (Saraiva et al., 2004).
8	Hydrastine, d-β-	An alkaloid anti-inflammatory agent; inhibits cytochrome P450 mediated oxidation (Raner et al., 2007).
9	Ouabain (−)-	Cardiac glycoside with antiviral activity (Su et al., 2008).
10	Valinomycin	A dodeca-depsipeptide antibiotic, anti inflammatory, lipo-oxygenase inhibitor. Known to be a potent antiviral agent against Severe Acute Respiratory Syndrome Corona virus (SARS CoV) (De Clercq, 2006, Wu et al., 2004).