title: (1S*,4'S*,5R*)-1-Isobutyl-5-meth-oxy-2',3-dimethyl-4,6-dioxa-2-aza-spiro-[bicyclo-[3.2.0]hept-2-ene-7,4'-isoquinoline]-1',3'(2'H,4'H)-dione.
abstract: In the isoquinoline ring system of the title compound, C(19)H(22)N(2)O(5), the N-heterocyclic ring is in a half-chair conformation. The dioxa-2-aza-spiro ring is essentially planar [maximum deviation of 0.025 (1) Å] and forms a dihedral angle of 23.51 (5)° with the benzene ring. In the crystal, mol-ecules are linked via weak inter-molecular C-H⋯O and C-H⋯N hydrogen bonds into chains along [010].
authors.forename: Hoong-Kun
authors.initials: HK
authors.lastname: Fun
authors.forename: Ching Kheng
authors.initials: CK
authors.lastname: Quah
authors.forename: Chengmei
authors.initials: C
authors.lastname: Huang
authors.forename: Haitao
authors.initials: H
authors.lastname: Yu