Structure and absolute configuration of 20β-Hydroxyprednisolone, a biotransformed product of predinisolone by the marine endophytic fungus Penicilium lapidosum

Molecules. 2014 Sep 3;19(9):13775-87. doi: 10.3390/molecules190913775.


The anti-inflammatory drug predinisolone (1) was reduced to 20β-hydroxyprednisolone (2) by the marine endophytic fungus Penicilium lapidosum isolated from an alga. The structural elucidation of 2 was achieved by 1D- and 2D-NMR, MS, IR data. Although, 2 is a known compound previously obtained through microbial transformation, the data provided failed to prove the C20 stereochemistry. To solve this issue, DFT and TD-DFT calculations have been carried out at the B3LYP/6-31+G (d,p) level of theory in gas and solvent phase. The absolute configuration of C20 was eventually assigned by combining experimental and calculated electronic circular dichroism spectra and 3JHH chemical coupling constants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA Primers
  • Magnetic Resonance Spectroscopy
  • Marine Biology*
  • Penicillium / metabolism*
  • Prednisolone / analogs & derivatives*
  • Prednisolone / chemistry
  • Prednisolone / metabolism
  • Spectrometry, Mass, Electrospray Ionization
  • Spectrophotometry, Infrared
  • Spectrophotometry, Ultraviolet


  • DNA Primers
  • Prednisolone