Synthesis of biologically active (-)-dehydroiso-β-lapachone and the determination of its absolute configuration

Chem Pharm Bull (Tokyo). 2011;59(6):753-6. doi: 10.1248/cpb.59.753.

Abstract

Synthesis of dehydoriso-β-lapachone (1) in both racemic and enantioenriched forms is achieved starting from reduced naphthoquinone equivalents. As for the synthesis of enantioenriched dehydroiso-β-lapachone, introduction of the asymmetric center was carried out by catalytic asymmetric epoxidation of the unfunctionalized trisubstituted olefin using Shi epoxidation diketal catalyst. The construction of isopropenylfurano-1,2-(β)-naphthoquinone was carried out by acidic ring-opening reaction of the epoxynaphthalene and the following diammonium cerium(IV) nitrate (CAN) oxidation. The absolute configuration of naturally occurring (-)-dehydroiso-β-lapachone was finally determined as (R) by comparing the measured optical rotation value of the synthetic (R)-dehydroiso-β-lapachone.

MeSH terms

  • Cerium / chemistry
  • Naphthoquinones / chemical synthesis
  • Naphthoquinones / chemistry*
  • Optical Rotation
  • Oxidation-Reduction
  • Stereoisomerism

Substances

  • Naphthoquinones
  • cerium nitrate
  • Cerium
  • beta-lapachone