NON-NATURAL 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; 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 cycloalkyl or heterocyclyl ring of 3 to 6 ring atoms; R<SUB>7</SUB> is (i) optionally substituted phenyl or monocyclic heteroaryl, or (ii) a radical of formula -CHR<SUB>4</SUB>Rs; R<SUB>4</SUB> is (a) optionally substituted C<SUB>1</SUB>-C<SUB>4</SUB> alkyl, C<SUB>1</SUB>-C<SUB>4</SUB> alkoxy, C<SUB>2</SUB>-C<SUB>4</SUB> alkenyl, C<SUB>2</SUB>-C<SUB>4</SUB> alkenyloxy, or C<SUB>2</SUB>-C<SUB>4</SUB> alkynyl, or (b) -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 -CH<SUB>2</SUB>Q or CH<SUB>2</SUB>OQ wherein Q is as defined in relation to R<SUB>6</SUB>; and R<SUB>5</SUB> is hydrogen, methyl, ethyl, or methyl substituted by 1, 2 or 3 fluoro atoms; 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 carbocyclic or heterocyclic ring of 3 to 6 ring atoms, optionally fused to a second, optionally substituted, carbocyclic or heterocyclic ring or 3 to 8 ring atoms; PROVIDED THAT the group R<SUB>7</SUB> is not the side chain of a natural amino acid.