Synonyms: Tert-butyl((3s)-1-(7-(but-2-yn-1-yl)-3-Methyl-1-((4-Methylquinazolin-2-yl)Methyl)-2,6-dioxo-2,3,4,5,6,7-hexahydro-1h-purin-8-yl)piperidin-3-yl)carbaMate;Boc-Linagliptin;[(3R)-1-[7-(2-Butynyl)-2,3,6,7-tetrahydro-3-methyl-1-[(4-methyl-2-quinazolinyl)methyl]-2,6-dioxo-1H-purin-8-yl]-3-piperidinyl]carbamic acid 1,1-dimethylethyl ester