This letter describes the total synthesis, preliminary biological evaluation and mechanism studies of a novel and structurally unique isochromanone, (±)7,8-dihydroxy-3-methyl-isochromanone-4 (1), a nature product contained in banana (Musa sapientum L.) peel. The bioassay showed that compound 1 displays potent antihypertensiveactivity in renal hypertensive rats and further mechanism studies revealed