A series of novel spirooxindole-O-naphthoquinone-tetrazolo[1,5-a]pyrimidine hybrids were designed, synthesized and evaluated as potent antitumor agents. These hybrids exhibited relatively high cytotoxic activity against cancer cell line HepG2 (IC₅₀ = 2.86–36.34 μM), while normal cell line LO2 was less sensitive to these hybrids (IC₅₀ = 36.37–248.39 μM). On the whole, among all the compounds tested, compound 4e, with a mean IC₅₀ value of 2.86 μM, was the most active. The novel hybrids may find their pharmaceutical applications after further investigations.

NAD(P)H: quinine oxidoreductase (NQO1) is a class of flavoprotein enzymes commonly expressed in eukaryotic cells. It actively participates in the metabolism of various quinones and their in vivo bi...

A series of novel 1,2-naphthoquinones possessing tetrazolo[1,5-a]pyrimidine scaffolds were synthesized in very good yields using one-pot condensation of 2-hydroxy-1,4-naphthoquinone, aldehydes, and 5-aminotetrazole. All the synthesized compounds were evaluated for their antitumor activity in vitro against HCT116 (human colon cancer) and HepG2 (human hepatoma) cell lines. Among the screened compounds, 4o, 4k, 4g, 4q, and 4s showed significant inhibitory activity against the two human cell lines.