Spectral Analysis of the Configuration and Solution Conformation of Dihydrodigoxigenin Epimers

Reductive inactivation of digitoxin by Eubacterium lentum cultures

“…Incubation of DHDT0 (150 mg), obtained by acid hydrolysis of E. lentum-produced DHDT3, with shaken F. roseum cultures led to the formation of a major product (109 mg). This product was shown to be identical to 20R-DHDGO by TLC, HPLC, mass spectrometry, and NMR spectrometry (1).…”

Reduction of digoxin to 20R-dihydrodigoxin by cultures of Eubacterium lentum

“…Even though the formation of large amounts of the reduced metabolites of DG3 (for example, dihydrodigoxin [DHDG3]) ( Fig. 1) in a significant minority of patients was known for some time (1,2,4,18,(21)(22)(23), it was only recently discovered that this conversion of DG3 to DHDG3 occurs within the gastrointestinal tract (17). Further, the organism Eubacterium lentum, a grampositive, obligate anaerobe and normal member of the intestinal flora, was identified as a bacterial species that can perform the reduction (5,6).…”

“…Reduction of the unsaturated ring of DG3 leads to the introduction of a new chiral center at C-20 (1,2). Standard chemical catalytic hydrogenation results in the formation of two DHDG3 epimers: 20R and 20S.…”