Abstract: Compounds of formula (I), inhibit HDAC activity: wherein A, B and D independently represent ?CH— or ?N—; W is —CH?CH— Or —CH2CH2—; R1 is a carboxylic acid group (—COOH), or an ester group which is hydrolysable by one or more intracellular carboxylesterase enzymes to a carboxylic acid group; R2 and R3 are selected from the side chains of a natural or non-natural alpha amino acid, provided that neither R2 nor R3 is hydrogen, or R2 and R3, taken together with the carbon to which they are attached, form a 3-6 membered saturated cycloalkyl or heterocyclyl ring; Y is a bond, —C(C?O)—, —S(?O)2—, —C(C?O)O—, —C(C?O)NR?—, —C(?S)—NR?, —C(?NH)NR? or —S(?O)2NR— wherein R? is hydrogen or optionally substituted C1-C6 alkyl; L1 is a divalent radical of formula -(Alk1)m(Q)(Alk2)p— wherein in, n, p, Q, AIk1 and AIk2 are as defined in the claims; X1 represents a bond; —C(?O); or —S(?O)2—; —NR4C(?O)—, —C(C?O)NR4—, —NR4C(?O)NR5—, —NR4S(?O)2—, or —S(?O)2NR4— wherein R4 and R5 are independently hydrogen or optionally substituted C1

Abstract: Compounds of formula (I), inhibit HDAC activity: wherein A, B and D independently represent ?CH— or ?N—; W is —CH?CH—Or —CH2CH2—; R1 is a carboxylic acid group (—COOH), or an ester group which is hydrolysable by one or more intracellular carboxylesterase enzymes to a carboxylic acid group; R2 and R3 are selected from the side chains of a natural or non-natural alpha amino acid, provided that neither R2 nor R3 is hydrogen, or R2 and R3, taken together with the carbon to which they are attached, form a 3-6 membered saturated cycloalkyl or heterocyclyl ring; Y is a bond, —C(?O)—, —S(?O)2—, —C(?O)O—, —C(?O)NR?—, —C(?S)—NR?, —C(?NH)NR? or —S(?O)2NR— wherein R? is hydrogen or optionally substituted C1-C6 alkyl; L1 is a divalent radical of formula -(Alk1)m(Q)n(Alk2)p- wherein m, n, p, Q.

Abstract: Compounds of formula (I), inhibit HDAC activity: wherein A, B and D independently represent ?CH— or ?N—; W is —CH?CH— Or —CH2CH2—; R1 is a carboxylic acid group (—COOH), or an ester group which is hydrolysable by one or more intra-cellular carboxylesterase enzymes to a carboxylic acid group; R2 and R3 are selected from the side chains of a natural or non-nat-ural alpha amino acid, provided that neither R2 nor R3 is hydrogen, or R2 and R3, taken together with the carbon to which they are attached, form a 3-6 membered saturated cycloalkyl or heterocyclyl ring; Y is a bond, —C(?O)—, —S(?O)2—, —C(?O)O—, —C(?O)NR?—, —C(?5)—NR?, —C(?NH)NR? or —S(?O)2NR — wherein R? is hydrogen or optionally substituted C1—C6 alkyl; L1 is a divalent radical of formula —(Alk1)m,(Q)n(Alk2)p— wherein m, n, p, Q, Alk1 and Alk2 are as defined in the claims; X1 represents a bond; —C(?O); or —S(?O)2—; —NR4C(?O)—, —C(?O)NR4—,— NR4C(?O)NR5—, —NR4S(?O)2—, or —S(?O)2NR4— wherein R4 and R5 are independently hydrogen or optionally substituted C1