Abstract: Novel pyridinones and their derivatives which are effective in treating or preventing Gram-negative bacterial infections are provided. The pyridinones are stable and easily derivatized; the methods by which these derivatizations occur is described. Two regioselective and functional group tolerant methods for the synthesis of the novel pyridinones are also provided. One such synthetic method involves reacting an imine and a Meldrum's acid derivative in solution. The other synthetic method is a solid phase synthesis of the pyridinones in which an imine is prepared bound to a solid support and a Meldrum's acid derivative is reacted with the imine. Novel imine intermediates useful in the solid phase and solution methods of synthesizing the pyridionones are also described.