The structure and stereochemistry of nine steroid metabolites isolated in quantities ranging from 0.15 to 1.8 mg were determined using a variety of NMR techniques, including heteronunclear multiple bond correlation (HMBC) using broadband adiabetic 13C pulses and phase-sensitive data presentation. Testosterone, and rostenedione and progesterone were oxidized with housefly cytochrome P450 6A1 enzyme reconstituted in vitro with housefly NADPH cytochrome P450 reductase and cytochrome b5. NMR analysis in CD3OD using a modified HMBC sequence as well as 2D heteronuclear single quantum correlation (HSQC), COSY and nuclear Overhauser and exchange spectroscopy (NOESY), combined with a detailed analysis of J couplings showed that hydroxylation occurs exclusively on the β-face of the steroids, at positions 2, 12, and 15.
- Broadband adiabatic shaped pulses
- Insect cytochrome P450
- Steroid A-ring conformation
ASJC Scopus subject areas
- Materials Science(all)