(dl)-3-Benyl-3,4-dihydroisocoumarin 6, a model of Feralolide, has been synt
hesized through 3-benzylisocoumarin 2 which is prepared by the condensation
of phenylacetyl chloride with homophthalic acid. Alkaline hydrolysis of 2
yielded the ketoacid 3 which is reduced to racemic hydroxy-acid 5. The latt
er is cyclodehydrated to furnish the title compound 6. Isocoumarin 2 and 3,
4-dihydroisocoumarin 6 have been screened in vitro for their antibacterial
activity.