Abstract
22-Methylene-3β-hydroxy-5β,20(S)-card-14-enolide (11) and 22-methylene-3β-hydroxy-5β,20(fi)-card-14-enolide (12) were synthesized from digitoxin (1). Attempts to prepare the 14β-hydroxy-22-methylene analogues were unsuccessful. The 20(R) isomer (12) was found in Na+,K+-ATPase inhibition studies to be twice as active as 14-dehydrodigitoxigenin (17). The 20(S) isomer (11) was significantly less active than 17. The hydrolysis of steroid 3β-tert-butyldimethylsilyl ethers was also found to be much more difficult than with nonsteroids.
Original language | English (US) |
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Pages (from-to) | 841-844 |
Number of pages | 4 |
Journal | Journal of medicinal chemistry |
Volume | 20 |
Issue number | 6 |
DOIs | |
State | Published - Jun 1 1977 |