Linagliptin impurity U Price Not Available 500 g Linagliptin impurity U Supplier Page Catalog Number CS-AQ-00181 Alternative Name(s) Linagliptin impurity U;tert-butylN-[(3R)-1-[7-(but-2-yn-1-yl)-3-methyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-8- yl]piperidin-3-yl]carbamate; Linagliptin Impurity 21 Molecular Formula C20H28N6O4 CAS# 666816-91-7 Purity >98% SMILES CC#CCN1C(C(NC2=O)=O)=C(N2C)N=C1N(CCC3)C[C@@H]3NC(OC(C)(C)C)=O Size 500 g Supplier Page https://www.clearsynth.com/en/CSAQ00181.html