title: Crystal structure of N-(3-oxo-butano-yl)-l-homoserine lactone.
abstract: 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.
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI, 53706, USA.
authors.forename: R W
authors.initials: RW
authors.lastname: Newberry
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI, 53706, USA; Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Dr., Madison, WI, 53706, USA.
authors.forename: R T
authors.initials: RT
authors.lastname: Raines
keywords: NBO analysis; carbonyl inter­action; crystal structure; homoserine lactone; hydrogen bonding