Enantioseparation and anti-rhinovirus activity of 3-benzylchroman-4-ones

In a series of homo-isoflavonoids, chloro-substituted rac-3-benzylchroman-4 -ones (3 d-f) showed an antiviral in vitro activity against selected picorn aviruses. In order to study the anti-rhinovirus activity of each stereoisom er, racemic mixtures of 3 d and 3 e were successfully resolved by high-perf ormance liquid chromatography, using a Whelk-O 1 column as chiral stationar y phase. The CD spectra confirm that the two eluates of each compound are e nantiomers but do not allow the assignment of their absolute configurations . The antiviral activity of the isomers and their racemates was tested in v itro against human rhinovirus serotype 1B and 14 infection, by means of the plaque reduction assay. All homoisoflavonoids tested exhibited an inhibito ry effect on rhinovirus replication with an activity depending on virus ser otype and compound. The two enantiomers of each compound and the correspond ing racemate were equipotent, clearly showing that the configuration of the chiral center in position 3 does not influence the activity against both r hinovirus serotypes. Chirality 11:495-500, 1999. (C) 1999 Wiley-Liss, Inc.