An alternative approach to the substitution of halopyridines is to employ pyridine-N-oxides (or benzo-fused variants) in conjunction with an electrophilic activating agent. In this way, a similarly broad range of active methylene nucleophiles may be heteroarylated, 8 along with alternative nucleophiles such as silyl ketene acetals and aldehydes (under conditions of enamine organocatalysis). We have previously reported the use of azlactones as nucleophiles for the substitution of activated pyridine-N-oxides. The intermediate azlactones served as electrophiles which could be opened with a diverse range of nucleophiles (alcohols, amines, organometallics and hydride reagents) to give -disubstituted amino acid derivatives; 12a alternatively, the use of water as a nucleophile triggered a hydrolysis/decarboxylation sequence to achieve a formal 'umpoled' synthesis of 2-(1-amidoalkyl)pyridines. We envisaged that a general synthesis of diverse pyridylcarboxylate derivatives would be possible using Meldrum's acids in place of azlactones (Scheme 1). Thus, activation of pyridine-N-oxides 1 and nucleophilic substitution by the Meldrum's acid derivatives 2 would generate an intermediate which could act as an electrophilic partner for ring-opening by a range of nucleophiles; the resulting carboxylic acids would undergo facile decarboxylation to yield the desired products 3. Below we describe the successful implementation of this simple three-component approach to substituted pyridylacetic acid derivatives, along with an investigation into the substrate scope of the process.