title: 6-Fluoro-4-oxochroman-2-carboxylic acid.
abstract: The title compound, C(10)H(7)FO(4), is an inter-mediate in the synthesis of the drug Fidarestat, (2S,4S)-2-aminoformyl-6-fluoro-spiro[chroman-4,4'-imidazolidine]-2',5'-dione. The di-hydro-pyran-one ring adopts an envelope conformation with the asymmetric C atom in the flap position. In the crystal, the mol-ecules are linked into zigzag chains along [100] by O-H⋯O hydrogen bonds and C-H⋯π inter-actions involving the benzene ring.
authors.affiliation: Key Laboratory of Drug Targeting of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu 610041, People's Republic of China.
authors.forename: Pei
authors.initials: P
authors.lastname: Chen
authors.forename: Shan
authors.initials: S
authors.lastname: Qian
authors.forename: Zhe-Qin
authors.initials: ZQ
authors.lastname: Shi
authors.forename: Yong
authors.initials: Y
authors.lastname: Wu