PayPal is of the largest global payment gateway solutions. They operate in almost every country including Brazil. It is easy to use and set up. PayPal has a very powerful API which can be used to customise the payments based on the merchants requirement.
In Brazil, 2checkout provides various payment methods including PayPal. Find out more about it here: http://www.analyzo.com/product-details/1430/301Payment Gateways (Brazil)