| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2028301 | Steroids | 2012 | 7 Pages |
New types of steroid-porphyrin conjugates derived from 20-hydroxyecdysone (20E) and 24-epibrassinolide (EBl) were synthesized. An exceptional regioselectivity in the reaction of both steroids with porphyrin boronic acids was found to give side-chain-conjugated boronic esters as sole products. UV–Vis-, fluorescence and NMR spectroscopy yielded similar data for all the studied compounds confirming the solvent driven supramolecular assembly with formation of J-aggregates. CD measurements of water diluted solutions showed a clear difference between 20E and EBl conjugates. The latter showed a strong supramolecular chirality, whereas 20E J-aggregates did not.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Steroid–porphyrin conjugates have been synthesized. ► Side-chain-conjugated boronic esters were formed as sole products. ► Spectral studies confirmed the solvent driven formation of J-aggregates. ► 24-Epibrassinolide conjugates showed a strong supramolecular chirality.
