AMINO ACID DERIVATIVES

摘要

Compounds of formula (I) have activity in alleviating the effects of impaired dopaminergic signaling, for example in the treatment of Parkinsons Disease: formula (I) wherein: R<SUB>1</SUB> is a carboxyl, carboxyl ester, or carboxamide group; R<SUB>2</SUB> and R<SUB>3</SUB> are independently hydrogen, or a group -C(=O)R<SUB>6</SUB> or -C(=O)OR<SUB>6 </SUB>wherein R<SUB>6</SUB> is C<SUB>1</SUB>-C<SUB>6</SUB> alkyl, or a group -CH<SUB>2</SUB>Q wherein Q is an optionally substituted monocyclic carbocyclic or heterocyclyl ring of 3 to 6 ring atoms; R<SUB>4 </SUB>and R<SUB>5</SUB>are independently (a) the side chain of a natural amino acid, or (b) optionally substituted C<SUB>1</SUB>-C<SUB>4</SUB> alkyl, C<SUB>2</SUB>-C<SUB>4</SUB> alkenyl, or C<SUB>2</SUB>-C<SUB>4</SUB> alkynyl, or (c) -CH<SUB>2</SUB>XCH<SUB>3</SUB>, -CH<SUB>2</SUB>CH<SUB>2</SUB>XCH<SUB>3</SUB>, or -CH<SUB>2</SUB>XCH<SUB>2</SUB>CH<SUB>3</SUB>, wherein X is -O-, S, or -NR<SUB>7</SUB> wherein R<SUB>7</SUB> is hydrogen, methyl or ethyl; or (d) -CH<SUB>2</SUB>Q or CH<SUB>2</SUB>OQ wherein Q is as defined in relation to R<SUB>6</SUB>; or R<SUB>4</SUB> and R<SUB>5</SUB> taken together with the carbon atom to which they are attached form an optionally substituted cycloalkyl or heterocyclic ring of 3 to 8 ring atoms, optionally fused to a second, optionally substituted, carbocyclic or heterocyclic ring.