The Macrolides are a group of Antibiotics whose activity stems from the presence of a macrolide ring and a large lactone ring in their structure. The most commonly-prescribed Macrolides are:
... the Amazon, the largest river in the world by volume, the Parana[?] with its impressive Iguaçu[?] falls, the Rio Negro, São Francisco[?], Xingu, Madeira and the Tapajós[?] ...