ISSN:
0021-8383
Schlagwort(e):
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The Synthesis of the 2-Desalkylcyclol of the Ergotamine-TyperBenzyloxycarbonyl-S-seryl-S-phenylalanyl-S-proline-p-nitrophenylester is synthesized by an improved route and oxidized by lead-tetraacetate to a mixture of the two diastereomeric (RSS, SSS) benzyloxycarbonyl-hydroxyglycyl-phenylalanyl-proline-p-nitrophenyl-esters. Treatment of this mixture with an aqueous potassium tartrate solution provides two epimeric cyclols (2-benzyloxycarbonylamino-5-benzyl-10b-hydroxy-3,6-dioxo-octahydro-8H-oxazolo[3,2-a]-pyrrolo-[2,1-c]-pyrazines), which are separated into the aci-form as well as into the natural form corresponding to the 2R:5S:10aS:10bS configuration of ergotamine.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/prac.19833250608