Patent ID: 7205384

Claim:
A process for the preparation of a compound of formula (IIa) reacting a compound of formula (IIIa), wherein Pg 1 is a first nitrogen protecting group and Pg 2 is a second nitrogen protecting group; and wherein Pg 1 and Pg 2 are selected such that the Pg 1 protecting group may be removed under conditions which do not remove the Pg 2 protecting group; with a suitable activating agent; to yield the corresponding compound of formula (IVa), wherein Q 1 is a leaving group; reacting the compound of formula (IVa) with a solution or suspension of a compound of formula (Va), wherein X is selected from the group consisting of Cl, Br and I; in an anhydrous organic solvent which is inert to the compound of formula (Va); to yield the corresponding compound of formula (VIa); subjecting the compound of formula (VIa) to selective de-protection, to yield the corresponding compound of formula (VIIa) or its corresponding acid addition salt; reacting the compound of formula (VIIa) with a compound of formula (VIIIa), wherein Pg 3 is an oxygen protecting group; and wherein Q 2 is a leaving group; in the presence of a tertiary amine base; in an aprotic organic solvent; to yield the corresponding compound of formula (IXa); de-protecting the compound of formula (IXa), to yield the corresponding compound of formula (IIa).