Design, synthesis, and biological evaluation of conformationally constrained aci-reductone mimics of arachidonic acid

J Med Chem. 1998 Feb 12;41(4):420-7. doi: 10.1021/jm970034q.

Abstract

An efficient and convergent synthesis has been developed for the production of 3,4-dihydroxy-5-[4-(2-((2Z)-hexenyl)phenyl)-3-(1Z)-but enyl]-2 (5H)-furanone (12d). This hydrophobic antioxidant is a stable conformationally constrained mimic of arachidonic acid (AA) (1) and its respective aci-reductone analogue (2). Pd(0)-catalyzed cross-coupling of 5-(3-butynyl)-3,4-dihydroxy-2(5H)-furanone (7) with 2-((2Z)-hexenyl)iodobenzene (8d) followed by Lindlar catalyzed hydrogenation produces 12d. Butynyl intermediate 7 is prepared from 2-(benzyloxy)-5-deoxyascorbic acid (15) by iodination (I2, PPh3, Imd), iodo substitution with lithium acetylide ethylenediamine complex (LiAEDA, HMPA, -5 degrees C), and benzyl group cleavage (Ac2O, Pyr, BCl3). The utility of this synthetic method was demonstrated by the synthesis of analogues 10e-k. Biological testing revealed that certain of these antioxidants inhibit both cyclooxygenase (COX) and 5-lipoxygenase (5-LO) with comparable efficacy as reported for aspirin and zileuton, respectively. The antioxidant activity of these aci-reductones, measured as a function of their inhibitory effect on CCl4-induced lipid peroxidation of hepatic microsomes, exceeds that produced by alpha-tocopherol. Synthetic routes and initial structure-activity relationships (SAR) for these novel mixed functioning antioxidants are presented.

MeSH terms

  • Animals
  • Antioxidants / chemical synthesis*
  • Antioxidants / chemistry
  • Antioxidants / pharmacology
  • Arachidonate 5-Lipoxygenase / metabolism
  • Arachidonic Acid / chemistry*
  • Cell Line, Transformed
  • Cell Nucleus / metabolism
  • Cyclooxygenase 1
  • Cyclooxygenase 2
  • Cyclooxygenase 2 Inhibitors
  • Cyclooxygenase Inhibitors / chemical synthesis
  • Cyclooxygenase Inhibitors / chemistry
  • Cyclooxygenase Inhibitors / pharmacology
  • Drug Design
  • Indicators and Reagents
  • Isoenzymes / metabolism
  • Lipopolysaccharides / pharmacology
  • Lipoxygenase Inhibitors / chemical synthesis
  • Lipoxygenase Inhibitors / chemistry
  • Lipoxygenase Inhibitors / pharmacology
  • Macrophages, Peritoneal / drug effects
  • Macrophages, Peritoneal / physiology
  • Malondialdehyde
  • Membrane Proteins
  • Models, Molecular
  • Molecular Conformation
  • Molecular Structure
  • NF-kappa B / metabolism
  • Prostaglandin-Endoperoxide Synthases / metabolism
  • Rats
  • Structure-Activity Relationship

Substances

  • Antioxidants
  • Cyclooxygenase 2 Inhibitors
  • Cyclooxygenase Inhibitors
  • Indicators and Reagents
  • Isoenzymes
  • Lipopolysaccharides
  • Lipoxygenase Inhibitors
  • Membrane Proteins
  • NF-kappa B
  • Arachidonic Acid
  • Malondialdehyde
  • Arachidonate 5-Lipoxygenase
  • Cyclooxygenase 1
  • Cyclooxygenase 2
  • Prostaglandin-Endoperoxide Synthases
  • Ptgs1 protein, rat