Method for obtaining dibenzylbutyrolactonic lignan; method for obtaining synthetic derivative from lignan, having anti-chagas chemoprophylaxis activity and therapeutic activity

Provided is an effective drug for the treatment of Chagas disease. A drug for the treatment of Chagas disease comprising cobevin and its semi-synthetic derivatives. The compound is, for example, cobebin, methylpluviatrid, o-acetylcubebin, o-methylcubebin, o-dimethylethylaminecubebin, hinokinin, 6,6′-dinitrohinokinin. These are obtained by extraction and purification from the leaves of Santoxiram narangiro or Piper cubeba and are at least 5 more than found by gentian violet and other compounds conventionally used for blood treatment and prevention of Chagas disease