title: 10'-Chloro-3',4'-dihydro-2'H-spiro-[cyclo-propane-1,7'(6'H)-pyrimido[2,1-a]isoquinolin]-6'-one.
abstract: In the title compound, C(14)H(13)ClN(2)O, the fused hydro-pyrimidine ring adopts an envelope conformation with one of the methyl-ene C atoms at the flap. The three-membered ring is approximately perpendicular to the attached isoquinoline ring system, with a dihedral angle of 89.44 (11)°. In the crystal, mol-ecules are linked by a weak C-H⋯π inter-action, forming a helical chain along the c axis.
authors.affiliation: Laboratory of Medicinal and Pharmaceutical Chemistry, Gifu Pharmaceutical University, Gifu 501-1196,  Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Okuda
authors.forename: Takashi
authors.initials: T
authors.lastname: Hirota
authors.forename: Yuta
authors.initials: Y
authors.lastname: Nishina
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishida