Synthesis of natural and non natural orthogonally protected lanthionines from N-tritylserine and allo-threonine derivatives

✍ Scribed by Christophe Dugave; André Ménez

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 863 KB
• Volume: 8
• Category: Article
• ISSN: 0957-4166
• DOI: 10.1016/s0957-4166(97)00109-2

✦ Synopsis

The reactivity of electrophiles derived from N-tritylserine, threonine and allothreonine esters toward a selection of nucleophiles was investigated. Best yields from substitution products were obtained with N-trityliodoalanine and soft nucleophiles such as thiols. This strategy was applied to the synthesis of lanthionines, the monosulfide analogs of cystine. Orthogonally protected sulfide adducts from L-and D-cysteines, threo-fJ-methyl-L-cysteine and D-penicillamine were isolated in 81-88% yield (ee>98%). This strategy was applied to the preparation of lanthionine and cyclolanthionine suitably protected for peptide synthesis. (~) 1997 Elsevier Science Ltd