A practical synthetic route to 4-acetylisocoumarins and the first total synthesis of AGI-7 (5) andsescandelin (4) are described. The readily available homophthalate 8 was transformed to the vinylogous amide ester13 in high overall yield. Upon treatment of 13 with refluxingaqueous formic acid, the desired 4-acetylisocoumarin (5) andits regioisomer 3-methyl-4-formylisocoumarin (17) wereproduced in a 3:1 ratio. After separation of the desiredproduct (5) from the unwanted minor isomer, the enantioselective reduction of AGI-7 by borane in the presence ofCorey's (S)-oxazaborolidine reagent afforded (+)-sescandelin(4) with a 93% ee.