New Synthetic Procedure for 2-Aryl-1,4-naphthoquinone-1-oxime Methyl Ethers with Potent Antitumor Activity

1,4-Naphthoquinone 1-oxime methyl ethers carrying an ester-substituted aryl pendant at 2-position were concisely prepared as seed compounds with structural flexibility for structure-activity relationship studies on antitumor activity. The key synthetic intermediate was a phthalide-tetralone spiro compound, which was provided by palladium-coupling reaction between 2-bromobenzoate and 1-tetralone followed by OsO4-NMO oxidation.