反应详情

β-lapachone, as well as its intermediates, derivatives and analogs thereof (also referred to herein as the “active compounds”), are described in Li, C. J. et al., J Biol. Chem., 1993. Unlike prior art β-lapachone syntheses as illustrated in Scheme 1, the synthesis of β-lapachone, in accordance with the present invention and generally illustrated in Scheme 2, commences with the reaction of 2-hydroxy-1,4-naphthoquinone with 1-bromo-3-methyl-2-butene in the presence of sodium iodide and triethylamine (a weak base) in dimethylsulfoxide (DMSO) to produce lapachol in up to 40% yield, after purification (20 g, up to 40% overall yield). Lapachol is then quantitatively converted to β-lapachone by treatment with sulfuric acid. The β-lapachone is purified by recrystallization from ethanol.