Crystal structure of N-(3-oxo-butano-yl)-l-homoserine lactone

Acta Crystallogr E Crystallogr Commun. 2016 Jan 9;72(Pt 2):136-9. doi: 10.1107/S2056989015024913. eCollection 2016 Feb 1.


The structure and absolute configuration of the title compound, C8H11NO4, which is a known quorum-sensing modulator, have been determined. The mol-ecule exhibits signs of an intra-molecular attractive carbon-yl-carbonyl n→π* inter-action between the amide and lactone ester groups, specifically - a short contact of 2.709 (2) Å between the amide oxygen atom and ester carbon atom, approach of the amide oxygen atom to the ester carbonyl group along the Bürgi-Dunitz trajectory, at 99.1 (1)°, and pyramidalization of the ester carbonyl group by 1.1 (1)°. Moreover, a similar n→π* inter-action is observed for the amide carbonyl group approached by the ketone oxygen donor. These inter-actions apparently affect the conformation of the uncomplexed mol-ecule, which adopts a different shape when bound to protein receptors. In the crystal, the mol-ecules form translational chains along the a axis via N-H⋯O hydrogen bonds.

Keywords: NBO analysis; carbonyl inter­action; crystal structure; homoserine lactone; hydrogen bonding.