Convenient synthesis of (S)-(+)-apomorphine from (R)-(-)-apomorphine
A method was devised for preparing (S)-(+)-apomorphine from (R)-(-)-apomorphine. Dehydrogenation of the dimethyl ether of (R)-(-)-apomorphine with 10% palladium-on-carbon carbon followed by reduction with sodium cyanoborohydride under acidic conditions resulted in quantitative racemization to given (R,S)-apomorphine dimethyl ether, which then was resolved with (-)-tartaric acid. Ether cleavage of (S)-(+)-apomorphine dimethyl ether (-)-tartrate with hydriodic acid in acetic anhydride yielded (S)-(+)-apomorphine, which was isolated as the hydrochloride salt in 99% enantiomeric excess.
PHARMACEUTICAL COMPOSITIONS OF (6AS)-6-METHYL-5,6,6A,7-TETRAHYDRO-4H-DIBENZO[DE,G]QUINOLINE-10,11-DIOL
This invention relates to pharmaceutical compositions for enhancing the solubility of (6aS)-6-methyl-5,6,6a,7-tetrahydro-4H-dibenzo[de,g]quinoline-10,11-diol and salt forms thereof.
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(2021/02/12)
PHARMACEUTICAL COMPOSITION FOR USE IN THE TREATMENT OF NEUROLOGICAL DISEASES
The present invention relates to pharmaceutical compositions for administration to mammals that include (6aS)-6-methyl-5,6,6a,7-tetrahydro-4H-dibenzo[de,g]quinoline-10,11-diol or a pharmaceutically acceptable salt thereof and at least one pharmaceutically acceptable excipient that provides pharmacokinetic profiles useful for the treatment of neurodegenerative diseases.
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(2021/02/12)
The palladium(0) Suzuki cross-coupling reaction as the key step in the synthesis of aporphinoids
We report a flexible approach to the total synthesis of 4,5-dioxoaporphines based on the palladium(0) catalyzed Suzuki cross-coupling of phenylboronic acids with sterically hindered 2-bromo phenyl acetates or bromo phenyl acetamides, followed by sequential bicyclization of biarylacetamides promoted by oxalyl chloride/Lewis acid. The reduction of 4,5-dioxoaporphines provides a chemoselective entry to aporphines, dehydroaporphines and 4-hydroxy- dehydroaporphines. A three-steps total synthesis for (±)-O,O′- dimethylapomorphine from readily accessible precursors is also reported.