Derivatization of Steroids for Obtaining Conjugates: Use as Vectors for Drug Delivery

Mono-mode microwave assisted additions of α-aminoacids (glycine/valine/phenylalanine) in the presence of K₂CO₃ to 16□ , 17□-epoxy-3□-hydroxypregnenolone (20) afford corresponding 17?-hydroxy-16-N-carboxyalkylaminosteroids (21a-c) in good yield. Similar conjugate addition of aminoacids to 16-dehydropregnenolone-3b -acetate (15), under identical conditions, affords 16-N-carboxyalkylamino steroidal derivatives (22a-c). All the products have been purified chromatographically and characterized spectroscopically. The obtained molecules can be conjugated with molecules/moieties for use as steroidal vectors.