Publikationsserver der RWTH Aachen University
Delta-Hydroxy-beta,beta-disubstituierte-beta-Aminosäuren: asymmetrische Synthese und Überführung in Dipeptide
Abstract
dc:descriptionThe present thesis describes a pathway for the synthesis of beta-mono- and beta-disubstituted delta-hydroxy-beta-amino acids having three contiguous stereogenic centers and the conversion of these molecules to dipeptides. The advantages of the herein described synthetic strategy relies on the extended variability concerning the substituents to be incorporated with excellent stereoselectivity in alpha-, beta- and gamma-position. The starting point of the seven step synthesis is the chiral auxiliary N,S-dimethyl-N-phenylsulfoximine, which is reacted with aldehydes or ketones to give allylic sulfoximines. The latter ones were gamma-hydroxylated using aldehydes, thus giving access to the two new stereogenic centers containing delta-N-methylsulfonimidoyl-substituted homoallylic alcohols which in the following step were aminated to homoallylic carbamates by applying trichloroacetylisocyanate and aqueous ammonia. Via stereospecific intramolecular aza-Michael-addition these carbamates are cyclised to N,O-protected delta-hydroxy-beta-amino-sulfoximines. After substitution of the sulfoximine moiety for nitril, basic hydrolysation and subsequent acidic work-up, beta-amino-delta-lactones are formed, which, according to well established literature procedures, can be easily condensed into beta,beta-dipeptides.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2004
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Roder, Daniel
- Contributors dc:contributor
-
- Gais, Hans-Joachim
Subjects
dc:subject × 10Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- ger
Identifiers
dc:identifier.*- OAI identifier oai:identifier
- oai:publications.rwth-aachen.de:62049