Zuo‐Liang Jing

An Investigation of the Inclusion Complex of β-Cyclodextrin with 8-Nitro-Quinoline in the Solid State

A supramolecular inclusion complex (1) was prepared between β-cyclodextrin and 8-nitro-quinoline, and its bound structure was investigated by X-ray crystallography in the solid state. The crystallographic study has shown that the inclusion complex 1 belongs to the Monoclinic system (space group: C2) with unit cell dimensions a = 19.269(5), b = 24.395(7), c = 16.095(4)Å, β = 107.816(5)°, and forms a channel-type polymeric supramolecule. In the crystal structure, the β-cyclodextrins exist as a head-to-head dimer by means of extensive hydrogen bonding across the secondary hydrogen groups of two symmetry-dependent β-cyclodextrins. Two guest molecules are included in the cavity of the different β-cyclodextrins, respectively, and the third is sandwiched in the interface of the dimer. The results indicate that the different inclusion behavior of 8-nitro-quinoline in β-cyclodextrin cavity results from differing host-guest hydrogen bonding as well as spatial constraints.

N′-(4-Hydroxy­benzyl­idene)benzohydrazide dimethyl­formamide solvate

The components of the title solvate structure, C14H12N2O2·C3H7NO, are connected via N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, leading to a chain motif.

4‐[(4‐Hydroxy­benzyl­idene)amino]‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one monohydrate

# 2005 International Union of Crystallography Printed in Great Britain – all rights reserved The title compound, C18H19N3O3, was prepared using 4hydroxybenzaldehyde and 4-amino-1,5-dimethyl-2-phenylpyrazolidin-3-one. The crystal structure shows that the title compound includes a water molecule, which forms O—H O hydrogen bonds with adjacent molecules and plays an important role in the stabilization of the crystal structure.

4-[(4-Hydroxy-3-methoxybenzylidene)amino]-1,5-dimethyl-2-phenylpyrazolidin-3-one

The central system (N1/N2/C7/O1/C11/C9/C10/N3/C8) is planar, with an r.m.s. deviation of fitted atoms of 0.041 Å, and the dihedral angle with the phenyl ring (C1–C6) is 53.48 (8) . The vanillin moiety (C12–C15/C17–C19/O2/O3/C16) is planar, with an r.m.s. deviation of fitted atoms of 0.023 Å; the dihedral angle between the central system and the vanillin moiety is 12.12 (7) . Intermolecular hydrogen bonds (O2—H2 O1) are observed (Table 1), which stabilize the crystal structure. The molecules associate in a zigzag pattern via intermolecular hydrogen bonds to form a supramolecular structure. Received 16 May 2005 Accepted 23 June 2005 Online 30 June 2005

4-[6-(4-Formyl-2-methoxyphenoxy)hexyloxy]-3-methoxybenzaldehyde

# 2005 International Union of Crystallography Printed in Great Britain – all rights reserved The title compound, C22H26O6, was prepared by the reaction of 4-hydroxy-3-methoxybenzaldehyde and 1,6-dibromohexane, displays molecular symmetry Ci, and has a crystallographic centre of inversion located at the mid-point of the C—C bond of the aliphatic chain. The zigzag aliphatic chain is coplanar with the aromatic rings of the vanillin groups.