Stereoselective Polymer-Supported Synthesis of Morpholine- and Thiomorpholine-3-carboxylic Acid Derivatives
Language English Country United States Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
- Keywords
- amino acid, bromoketone, morpholine, nitrobenzenesulfonyl chloride, oxazine, solid-phase synthesis, stereoselective synthesis, thiazine, thiomorpholine,
- MeSH
- Fluorenes chemistry MeSH
- Carboxylic Acids chemical synthesis chemistry MeSH
- Morpholines chemical synthesis chemistry MeSH
- Oxazines chemical synthesis chemistry MeSH
- Polymers chemistry MeSH
- Stereoisomerism MeSH
- Solid-Phase Synthesis Techniques methods MeSH
- Thiazines chemical synthesis chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Fluorenes MeSH
- Carboxylic Acids MeSH
- Morpholines MeSH
- Oxazines MeSH
- Polymers MeSH
- thiamorpholine MeSH Browser
- Thiazines MeSH
Herein we report the polymer-supported synthesis of 3,4-dihydro-2H-1,4-oxazine-3-carboxylic acid derivatives using immobilized Fmoc-Ser(tBu)-OH and Fmoc-Thr(tBu)-OH as the starting materials. After the solid-phase-synthesis of N-alkyl-N-sulfonyl/acyl intermediates, the target dihydrooxazines were obtained using trifluoroacetic acid-mediated cleavage from the resin. This approach was also studied for the preparation of dihydrothiazines from immobilized Fmoc-Cys(Trt)-OH. Inclusion of triethylsilane in the cleavage cocktail resulted in the stereoselective formation of the corresponding morpholine/thiomorpholine-3-carboxylic acids. Stereochemical studies revealed the specific configuration of the newly formed stereocenter and also the formation of stable N-acylmorpholine rotamers.
References provided by Crossref.org
Synthesis of chiral 1,4-oxazepane-5-carboxylic acids from polymer-supported homoserine
