Certain simple benzopyrones have clinical medical value as an edema modifiers. Coumarin and other benzopyrones, such as 5,6 benzopyrone, 1,2 benzopyrone, diosmin and others are known to stimulate macrophages to degrade extracellular albumin, allowing faster resorption of edematous fluids.
Naturally occurring coumarin is also the basis for various 4-hydroxybenzopyrone-based molecules which occur naturally dicoumarol and are made synthetically warfarin and function as anticoagulants.
^full content of NEJM article. Treatment of Lymphedema of the Arms and Legs with 5,6-Benzo-[alpha]-pyrone. John R. Casley-Smith, Robert Gwyn Morgan, and Neil B. Piller Volume 329:1158-1163 October 14, 1993 Number 16.