A brief overview on recent advances in spiro[chromane-2,4'-piperidine]-4(3H)-one-functionalized compounds in medicinal chemistry research.

The spiro[chromane-2,4'-piperidine]-4(3H)-one is an important pharmacophore. It is a structural component in many drugs, drug candidates (or lead compounds) and various biochemical reagents. This review demonstrated an impressive progress in syntheses of spiro[chromane-2,4'-piperidine]-4(3H)-one-derived compoundsin the recent years and focuses on features of their biological relevance's.

3-(4-Nitro-benz-yl)-4H-chromen-4-one.

In the title compound, C16H11NO4, the dihedral angle between the ten-membered chromen-4-one ring system (r.m.s.

3-Bromo-chroman-4-one.

The heterocyclic ring of the title compound, C9H7BrO2, obtained by bromination of 4-chromanone with copper bromide, adopts a half-chair conformation. The supramol-ecular structure is governed by a weak C-H⋯O hydrogen bond. There is also π-π stacking between symmetry-related benzene rings; the centroid-centroid distance is 3.

3-(3-Nitro-benz-yl)-4H-chromen-4-one.

In the title compound, C16H11NO4, the dihedral angle between the 10-membered coplanar chromone ring system and the benzene ring is 77.83 (3)°. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.

3-(3,4-Dichloro-benzyl-idene)chroman-4-one.

The distinctive feature of the structure of the title compound, C(16)H(10)Cl(2)O(2), is the formation of a zigzag chain along [100] via Cl⋯Cl inter-actions [3.591 (1) and 3.631 (1) Å].

2,4-Dibromo-1,3-dimeth-oxy-5-methyl-benzene.

The title compound, C(9)H(10)Br(2)O(2), crystallizes with two mol-ecules in the asymmetric unit. The two mol-ecules are essentially planar with slight differences in the (Br)C-C-O-C(H(3)) torsion angles [-176.7 (2) and -172.

(E)-3-(4-Cyclo-hexyl-3-fluoro-benzyl-idene)chroman-4-one.

The title compound, C(22)H(21)FO(2), exhibits substitutional disorder of the F atom and a H atom in the asymmetric unit with different occupancies, the refined F:H ratio being 0.80 (2):0.20 (2).

3-(3-Meth-oxy-benzyl-idene)chroman-4-one.

In the title compound, C(17)H(14)O(3), the dihedral angle between the meth-oxy-benzene unit and the benzene ring of the chromanone system is 64.12 (3)°. The crystal structure is stabilized by weak C-H⋯O inter-actions.

Anti-inflammatory activities of selected synthetic homoisoflavanones.

Four homoisoflavanones of the 3-benzylidene-4-chromanone type, some of which were previously isolated from Caesalpinia pulcherrima, were synthesised to determine their anti-inflammatory activity and cytotoxicity. A range of four different homoisoflavanones (compounds 4a-4d) were synthesised from the corresponding substituted phenols. ¹H- and ¹³C-NMR data together with high-resolution mass spectroscopy data were employed to elucidate the structures.

3-Benzyl-5,7-dimeth-oxy-chroman-4-ol.

In the crystal structure of the title compound, C(18)H(20)O(4), O-H⋯O hydrogen bonds connect the mol-ecules in parallel layers along the b axis.