Synthesis of new spiro-naphthoquinone prepared from lawsone compound and test of antioxidant activity

The spiro substances gained a lot of attention in serving as scaffolds in modern drug discovery. Spiro compounds present in natural products such as analgesic morphine, the antibiotic monensin, cannabispirenone A, and alkaloid citrinalin A. In regards to the spiro compound's properties of pharmacological, the synthetic method development which enables a simple access toward these substances are preferable. The spiro naphthol derivatives were synthesized through a hydroxyl naphthoquinone and isatin condensation process in non-solvent reaction, a good condition, in relation to the impact to the environment and waste production reduction. The synthesized product showed a radical scavenging capacity as tested with DPPH method and are expected to be potential for pharmacological interest. New Spiro-naphthoquinone compounds were synthesized buy using isatin and lawsone as the main precursor with hydrazine and malononitrile as the third combination precursor. Combination between isatin, lawsone, and hydrazine is not produced but the combination between isatin, lawsone, and malononitrile is produced under the same condition. Antioxidant of the new spiro- naphthoquinone compound produced is categorized as weak with IC₅₀ is 266.87 mg/L.