A method for the preparation of a complex of Formula IA: wherein the subscript n is 1 or 2 R 1 is a member selected from the group consisting of hydrogen, halo and C 1 -C 6 alkyl; V is a member selected from the group consisting of oxygen and a single bond; W is a member selected from the group consisting of C 1 -C 6 alkylene, C 2 -C 6 alkenylene, C 2 -C 6 alkynylene, C 3 -C 10 cycloalkylene, and (C 3 -C 10 cycloalkylene)(C 1 -C 6 alkylene); X is a member selected from the group consisting of oxygen, a single bond, and NR a; and Y is a member selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 1 -C 6 hydroxyalkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 3 -C 10 cycloalkyl, (C 3 -C 10 cycloalkyl)C 1 -C 4 alkyl, (C 1 -C 4 alkyloxy)C 1 -C 3 alkyl, (C 3 -C 10 cycloalkyloxy)C 1 -C 3 alkyl, (amino)C 1 -C 3 alkyl, (C 1 -C 4 alkylamino)C 1 -C 3 alkyl, (C 1 -C 6 alkyl)carbonyl, (C 2 -C 6 alkenyl)carbonyl, (C 2 -C 6 alkynyl)carbonyl, (C 1 -C 6 alkyl)sulfonyl, (C 2 -C 6 alkenyl)sulfonyl, and (C 2 -C 6 alkynyl)sulfonyl, wherein alkyl, alkenyl, alkynyl and cycloalkyl groups or portions of W, X and Y are optionally partly or completely fluorinated and optionally mono- or disubstituted by identical or different substituents selected from chlorine, hydroxy, C 1 -C 3 alkyl, C 1 -C 3 alkoxy, and C 3 -C 6 cycloalkyl, and in cycloalkyl groups or portions one or two methylene groups are optionally replaced independently of one another by O, S, CO, SO, SO 2 or NR b, and one or two methyne groups are optionally replaced by N; R a is a member independently selected from the group consisting of H, C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl and (C 1 -C 4 alkyl)carbonyl, wherein alkyl and cycloalkyl groups or portions are optionally partly or completely fluorinated; each R b is a member independently selected from the group consisting of H, C 1 -C 4 alkyl and (C 1 -C 4 alkyl)carbonyl, wherein alkyl groups or portions are optionally partly or completely fluorinated; or a pharmaceutically acceptable salt thereof; comprising: (a) reacting a compound of Formula II with a reducing agent in the presence of an activating group to form a compound of Formula III and (b) contacting said compound of Formula III with an amino acid to form said complex of Formula IA; wherein steps (a) and (b) are performed without purification of said compound of Formula III and wherein steps (a) and (b) are performed sequentially without an intervening protection or deprotection step. wherein the subscript n is 1 or 2 R 1 is a member selected from the group consisting of hydrogen, halo and C 1 -C 6 alkyl; V is a member selected from the group consisting of oxygen and a single bond; W is a member selected from the group consisting of C 1 -C 6 alkylene, C 2 -C 6 alkenylene, C 2 -C 6 alkynylene, C 3 -C 10 cycloalkylene, and (C 3 -C 10 cycloalkylene)(C 1 -C 6 alkylene); X is a member selected from the group consisting of oxygen, a single bond, and NR a; and Y is a member selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, C 1 -C 6 hydroxyalkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 3 -C 10 cycloalkyl, (C 3 -C 10 cycloalkyl)C 1 -C 4 alkyl, (C 1 -C 4 alkyloxy)C 1 -C 3 alkyl, (C 3 -C 10 cycloalkyloxy)C 1 -C 3 alkyl, (amino)C 1 -C 3 alkyl, (C 1 -C 4 alkylamino)C 1 -C 3 alkyl, (C 1 -C 6 alkyl)carbonyl, (C 2 -C 6 alkenyl)carbonyl, (C 2 -C 6 alkynyl)carbonyl, (C 1 -C 6 alkyl)sulfonyl, (C 2 -C 6 alkenyl)sulfonyl, and (C 2 -C 6 alkynyl)sulfonyl, wherein alkyl, alkenyl, alkynyl and cycloalkyl groups or portions of W, X and Y are optionally partly or completely fluorinated and optionally mono- or disubstituted by identical or different substituents selected from chlorine, hydroxy, C 1 -C 3 alkyl, C 1 -C 3 alkoxy, and C 3 -C 6 cycloalkyl, and in cycloalkyl groups or portions one or two methylene groups are optionally replaced independently of one another by O, S, CO, SO, SO 2 or NR b, and one or two methyne groups are optionally replaced by N; R a is a member independently selected from the group consisting of H, C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl and (C 1 -C 4 alkyl)carbonyl, wherein alkyl and cycloalkyl groups or portions are optionally partly or completely fluorinated; each R b is a member independently selected from the group consisting of H, C 1 -C 4 alkyl and (C 1 -C 4 alkyl)carbonyl, wherein alkyl groups or portions are optionally partly or completely fluorinated; or a pharmaceutically acceptable salt thereof; comprising: (a) reacting a compound of Formula II with a reducing agent in the presence of an activating group to form a compound of Formula III and (b) contacting said compound of Formula III with an amino acid to form said complex of Formula IA; (a) reacting a compound of Formula II with a reducing agent in the presence of an activating group to form a compound of Formula III and (b) contacting said compound of Formula III with an amino acid to form said complex of Formula IA;