Linagliptin Impurity 6 (Linagliptin (S)-Isomer) Catalogue L562356 CAS 668270-11-9 M.W 472.54 M.F C25H28N8O2 Specifications FAQs 8-[(3S)-3-Amino-1-piperidinyl]-7-(2-butyn-1-yl)-3,7-dihydro-3-methyl-1-[(4-methyl-2-quinazolinyl)methyl]-1H-purine-2,6-dione