The title compound, C(12)H(14)BrN(3)O, is built up from two fused six-membered rings and one six-membered ring linked through a spiro C atom. The hydro-pyrimidine ring has an envelope conformation and the cyclo-hexane ring is in a chair conformation. In the crystal, mol-ecules are linked by N-H⋯O and N-H⋯N hydrogen bonds, forming a mol-ecular tape along the b axis.

The title compound, C30H28ClN3O2, features two spiro links, one connecting the piperidine and pyrrolidine rings, and the other connecting the pyrrolidine ring and indole residue. The configuration about the ethene bond is E. The piperidine ring adopts a half-chair conformation where the C atom connected to the spiro-C atom lies 0.713 (3) Å out of the plane of the remaining five atoms (r.m.s. de...

The title compound, C19H16F4O4, was prepared by the condensation reaction of 2,6-di-fluoro-benzaldehyde and penta-erythritol. The whole mol-ecule is generated by twofold rotational symmetry. The two six-membered O-heterocycles adopt chair conformations through a shared spiro-carbon atom that is located on the crystallographic twofold rotation axis. In this conformation, the two aromatic rings a...

The title compound, C34H38ClN5O2, has spiro links connecting the pyrrolidine ring and indole residue, as well as the piperidine and pyrrolidine rings. A half-chair conformation is found for the piperidine ring with the C atom connected to the spiro-C atom lying 0.738 (4) Å out of the plane of the remaining five atoms (r.m.s. deviation = 0.0407 Å). The methyl-ene C atom is the flap in the envelo...

The title compound, C(21)H(21)N(3)O(3), was synthesized by a multi-component 1,3-dipolar cyclo-addition of azomethine ylide, derived from isatin and proline by a deca-rboxylative route, and (E)-1-phenyl-2-nitro-propene. In the mol-ecule, the spiro junction links a planar oxindole ring and a pyrrolidine ring in an envelope conformation. The mol-ecular packing is stabilized by an inter-molecular ...

In the title compound, C(14)H(18)N(2)O, both the spiro-linked five-membered rings adopt envelope conformations, with a C atom as the flap in one ring and an N atom in the other. The dihedral angle between the two four-atom planes is 80.46 (8)°. In the crystal, the mol-ecules are linked by N-H⋯O hydrogen bonds to generate C(4) chains propagating in [010].

In the title compound, C15H10Br2, each mol-ecule is situated on special postion mm, so the asymmetric unit contains one-quater of a mol-ecule. The 2,7-di-bromo-9H-fluorene fragment and three spiro-cyclo-propane C atoms lie on different planes, which are perpendicular to each other. In the crystal, π-π inter-actions between aromatic rings [inter-centroid distance = 3.699 (3) Å] pack the mol-ecul...

In the title compound, C(37)H(40)N(4)O(2), the xanthene and spiro-lactam rings are almost planar, with r.m.s. deviations from the mean planes of 0.223 (2) and 0.057 (2) Å, respectively, and form a dihedral angle of 85.76 (3)°. The dihedral angle between the xanthene mean plane and the benzene ring is 87.16 (5)°. One of the two ethyl groups of one of the diethyl-amino groups is disordered over t...

In the title compounds 4,11-dihy-droxy-13-methyl-1,8-di-p-tolyl-2,9-di-thia-13- aza-dispiro-[4.1.4(7).3(5)]tetra-decan-6-one, C26H31NO3S2, (I), and 13-benzyl-4,11-dihy-droxy-1,8-bis-(4-methyl-phen-yl)-2,9-di-thia-13-aza-dispiro-[4.1.4(7).3(5)]tetradecan-6-one, C32H35NO3S2, (II), the piperidine rings adopt distorted chair conformations. The thio-phene rings in (I) have envelope conformations, wi...

In the title compounds, C22H20N2O4S, (I), and C22H19ClN2O4S, (II), the pyrrolidine rings have twist conformations on the spiro-spiro C-C bonds. In (I), the five-membered ring of the oxindole moiety has an envelope conformation with the spiro C atom as the flap, while in (II) this ring is flat (r.m.s. deviation = 0.042 Å). The mean planes of the pyrrolidine rings are inclined to the mean planes ...