On the Reaction of 2-Alkanoylnaphthohydroquinones with Hydroxylamine: Access to Cytotoxic 2-(Hydroxyamino)-1,4-naphthoquinone and Their 3-(Hydroxyimino)alkyl Analogous

Oximes are known for their anti-inflammatory, antimicrobial, antioxidant, and anticancer activities. Frequently, modification of biologically active carbonyl compounds into oximes leads to increased activity. The present study reports the reactivity 2-alkanoylnaphthohydroquinones against hydroxylamine under aerial conditions. Results show that, depending on structure hydroquinones, reaction proceeds through two different chemical pathways produce 2-(hydroxyamino)-1,4-naphthoquinone C-3 (hydroxyimino)alkyl derivatives. Both formation quinoid oxidation C-C cleavage reactions hemiaminal intermediates discussed. In vitro screening substituted 1,4-naphthoquinones a panel cancer cells reveals moderate cytotoxic Compound 19, 2-(hydroxyamino)-1,4-naphthoquinone, stands out by its potency prostate as shown lowest IC50 value (8.08 μM) best selectivity index (3.90).