Synthesis and evaluation of novel chromone analogs for their inhibitory activity against interleukin-5.

A novel series of chromone analogs were synthesized and evaluated for their inhibitory activity against interleukin-5. Among them compounds 5-Cyclohexylmethoxy-3-(4-hydroxybenzyl)-4H-chromen-4-one (6a, 98% inhibition at 30 microM, IC50<3.0 microM) and 5-Cyclohyxylmethoxy-3-(hydroxymethyl)-4H-chromen-4-one (8a, 84% inhibition at 30 microM, IC50=7.6 microM) showed most potent activity. The structural requirement of chromone analogs possessing the inhibitory activity against IL-5 could be summarized as: (i) importance of hydrophobic group such as cyclohexylmethoxy at 5th position of ring A, (ii) requirement of ring B with small size of hydrogen bonding group with electron donating property such as phenolic hydroxyl group at 4th position and (iii) planarity of the chromen-4-one ring. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.