Patent ID: 11944687
Assignee: ALNYLAM PHARMACEUTICALS, INC.
Field: Pharmaceuticals (Chemistry)
Classification: CPC A  C  Y | IPC A  C

Claim 0:
1. A process for preparing a compound of formula (A), wherein
each occurrence of X is hydrogen or a hydroxy protecting group;
each occurrence of Y is an amine protecting group;
n is 0-20;
each occurrence of q, r and s is independently 1-7;
L is a linking group;
R1 is an iRNA agent;
the compound of formula (A) contains no more than 1000 ppm of metal impurities; and
the compound of formula (A) contains no more than 0.5% by weight of each of the following two urea side products, and
each of the following saccharide compounds, the process comprising:
(a) converting a compound of formula (VI) to a compound of formula (VII):, wherein said converting step comprises:
(i) reacting the compound of formula (VI) with a base;
(ii) reducing the product of step (i); and
(iii) reacting the product of step (ii) with an acid, and
(b) converting the compound of formula (VII) to a compound of formula (A).