116252-52-9

Heterocyclic compounds and salts according to formula (I), which are pyrimidinone derivatives, described herein exhibit human neutrophil elastase inhibitory properties, and useful for treating diseases or conditions in which HNE is implicated.

This invention relates to heterocyclic compounds, which are pyrimidinone derivatives having human neutrophil elastase inhibitory properties, and their use in therapy.

3-Lithiated 4-terNbutyl-imidazol-2-ylidene, 3-lithiated 4-tert butyl-thiazol-2-ylidene, and the ZnBr species of the latter, are shown to be stable carbenes by X-ray crystal structure determination. The crystal data are confirmed by 13C-NMR investigations in solution and quantum-chemical calcula tions. The exceptional stability of these acyl anion equiva-lents is due to the p(n) stabilization of the carbene carbon atoms by the adjacent amino (thio) substituents, as is also the case in the structurally related stable carbenes, which have recently been isolated for the first time by A. J. Arduengo III et al., and in stable nitrenium ions, as found by our group. VCH Verlagsgesellschaft mbH.