Harbinatic acid, a novel and potent DNA polymerase beta inhibitor from Hardwickia binata

J Nat Prod. 1999 Jul;62(7):1000-2. doi: 10.1021/np990099r.


Bioassay-guided fractionation of an active methyl ethyl ketone extract of Hardwickia binata, using an assay sensitive to DNA polymerase beta inhibition, resulted in the isolation of a potent inhibitor. This proved to be a novel diterpenoid, which has been named harbinatic acid (1). The structure of 1 was established as 3alpha-O-trans-p-coumaroyl-7-labden-15-oic acid from spectroscopic analysis and by comparison with the published data for a structurally related compound. Compound 1 strongly inhibited calf thymus DNA polymerase beta, with an IC(50) value of 2.9 microM.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • DNA Polymerase beta / antagonists & inhibitors*
  • Diterpenes / isolation & purification*
  • Diterpenes / pharmacology
  • Enzyme Inhibitors / isolation & purification*
  • Enzyme Inhibitors / pharmacology
  • Fabaceae / chemistry*
  • India
  • Magnetic Resonance Spectroscopy
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Plants, Medicinal*


  • Diterpenes
  • Enzyme Inhibitors
  • Plant Extracts
  • harbinatic acid
  • DNA Polymerase beta