... Tetrahedron: Asymmetry. Volume 15, Issue 2, 26 January 2004, Pages 341–345. Cover image Cover image. Enzymatic resolution of a quaternary stereogenic centre as the key step in the synthesis of (S)-(+)citalopram. ... 13, Acetonitrile, 5, 1.5, 26, 50, 75, 74, 15. a ...