Synthetic studies on thiostrepton family of peptide antibiotics: synthesis of the cyclic core portion containing the dehydropiperidine, dihydroquinoline, l-valine, and masked dehydroalanine segments

The cyclic core portion containing the dehydropiperidine, dihydroquinoline, l-valine, and masked dehydroalanine (i.e., β-phenylselenoalanine) segments of the thiostrepton family of peptide antibiotics was synthesized via the consecutive coupling of these four segments followed by cyclization at the amide bond between the dehydropiperidine and masked dehydroalanine segments.