24861
The pyrido [ 3 , 2 - d ] pyrimidine ligands have significantly reduced hERG binding compared to clinical stage compound PF - 3893787 while showing good affinities at the human and rodent histamine receptors .
 Chemical: pyrido [ 3 , 2 - d ] pyrimidine; Chemical: PF - 3893787; Chemical: histamine
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: pyrido [ 3 , 2 - d ] pyrimidine; Chemical: PF - 3893787; Chemical: histamine