Design, synthesis and anti-influenza virus activity of furan-substituted spirothiazolidinones

Synthesis of new N‐(3‐oxo‐1‐thia‐4‐azaspiro[4.5]decan‐4‐yl)pyridine‐3‐carboxamide derivatives and evaluation of their anti‐influenza virus and antitubercular activities

“…The introduction of a methyl group at position 2 of the spiro system proved to have a positive effect as neither of the compounds 2a-f displayed anti-influenza virus activity (Table 1). Hence, the SAR for these nicotinohydrazide-spirothiazolidinones is fully consistent with the previously reported SAR for the imidazo[2,1-b]thiazole, [8] 1-adamantyl, [9] 5-chloro-2-hydroxy/methoxyphenyl, [10,11] 2-methylfuran-3-yl, [13] and 5-chloro-3-methylindole [14] series.…”

“…The new compounds were characterized by combustion analysis and infrared (IR), 1 H NMR (nuclear magnetic resonance), and 13 C NMR (attached proton test [APT] ) spectral studies.…”

“…[ 8 ] For the lead compound, A1 , the average EC 50 for different strains of human influenza A/H3N2 was 9.6 µM and the IC 50 (cytostatic activity) was 93 µM, yielding a selectivity index of 10. Subsequent structure–activity relationship (SAR) analyses demonstrated that antiviral efficacy and selectivity show no drastic change when the aromatic part is replaced by 1‐adamantyl ( A2 ), [ 9 ] 5‐chloro‐2‐hydroxy/methoxyphenyl ( A3 ), [ 10,11 ] 4‐chlorophenoxymethyl ( A4 ), [ 12 ] or 2‐methylfuran‐3‐yl ( A5 ) [ 13 ] (Figure 1). The compounds were proven to act as influenza A/H3N2 virus fusion inhibitors by hindering the conformational change of the viral hemagglutinin (HA) at low pH, a process required to provoke the fusion of the viral envelope and endosomal membrane.…”

A review on advances in synthetic methodology and biological profile of spirothiazolidin‐4‐ones

“…A multistep synthesis of thia‐4‐azaspirofuran‐3‐carboxamides derivatives 53 has been reported by Apaydin and coworkers [46]. The methyl ester of furan‐3‐carboxylic acid 51 on refluxing with hydrazine hydrate in ethanol furnished hydrazide 52 , which on condensation with ketones 44 and sulfanylacetic acid/2‐sulfanylpropanoic acid 3 in toluene yielded 53 (Scheme 14).…”

Spiro Derivatives in the Discovery of New Pesticides: A Research Review

“…Spiro compounds are widely used in the medical field due to their fungicide, bactericidal, , antidisease, antiviral, , anticancer, , antitumor, and antioxidant properties. Despite their wide application in these areas, between 2010 and 2021 there were fewer than 140 reports of their use in the field of pesticides, although such applications are increasing every year (Figure , left).…”