Details for Patent: 9,388,104
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Title: | Chemically modified small molecules |
Abstract: | Provided are methods of preparing a monodisperse oligo (ethylene glycol) reagent composition. |
Inventor(s): | Bentley; Michael D. (Huntsville, AL), Viegas; Tacey X. (Madison, AL), Goodin; Richard R. (Fayetville, TN), Cheng; Lin (Huntsville, AL), Zhao; Xuan (Huntsville, AL) |
Assignee: | Nektar Therapeutics (San Francisco, CA) |
Filing Date: | Apr 08, 2014 |
Application Number: | 14/248,245 |
Claims: | 1. A method of preparing a monodisperse oligo (ethylene glycol) reagent composition, comprising: reacting a halo-terminated oligo (ethylene glycol) having (m) monomer subunits and a methoxy end-capping group with a first hydroxyl-terminated oligo (ethylene glycol) having (n) monomer subunits, wherein the first hydroxyl-terminated oligo (ethylene glycol) structure is HO--(CH.sub.2CH.sub.2O).sub.n--H, under conditions effective to displace said halo group to thereby form an oligo (ethylene glycol) having (m)+(n) monomer subunits (OEG.sub.m+n), wherein reacting the halo-terminated oligo(ethylene glycol) with the first hydroxyl-terminated oligo (ethylene glycol) comprises adding a 1:1 molar ratio of the halo-terminated oligo(ethylene glycol) to the first hydroxyl-terminated oligo (ethylene glycol) in a solution; converting the terminal hydroxyl group of OEG.sub.m+n into a halo group, --X, to form OEG.sub.m+n-X; and reacting OEG.sub.m+n-X with a second hydroxyl-terminated oligo (ethylene glycol) having (n) monomer subunits, wherein the second hydroxyl-terminated oligo structure is HO--(CH.sub.2CH.sub.2O).sub.n--H, under conditions effective to displace said halo group to thereby form an oligo(ethylene glycol) having (m)+2(n) monomer subunits (OEG.sub.m+2n), wherein reacting the OEG.sub.m+n-X with the second hydroxyl-terminated oligo (ethylene glycol) comprises adding a 1:1 molar ratio of the OEG.sub.m+n-X to the second hydroxyl-terminated oligo (ethylene glycol) in a solution; wherein (m) and (n) each independently range from 1-10, and wherein (OEG.sub.m+2n) corresponds to the structure CH.sub.3O(CH.sub.2CH.sub.2O).sub.m+2nH, and is present as part of a monodisperse composition of CH.sub.3O(CH.sub.2CH.sub.2O).sub.m+2nH. 2. A method of preparing a monodisperse oligo (ethylene glycol) reagent composition, comprising: reacting a halo-terminated oligo (ethylene glycol) having (m) monomer subunits and a methoxy end-capping group with a first hydroxyl-terminated oligo (ethylene glycol) having (n) monomer subunits, wherein the first hydroxyl-terminated oligo (ethylene glycol) structure is HO--(CH.sub.2CH.sub.2O).sub.n--H, under conditions effective to displace said halo group to thereby form an oligo (ethylene glycol) having (m)+(n) monomer subunits (OEG.sub.m+n), wherein reacting the halo-terminated oligo(ethylene glycol) with the first hydroxyl-terminated oligo (ethylene glycol) comprises adding a 1:1 molar ratio of the halo-terminated oligo(ethylene glycol) to the first hydroxyl-terminated oligo (ethylene glycol) in a solution; converting the terminal hydroxyl group of OEG.sub.m+n into a halo group, --X, to form OEG.sub.m+n-X; reacting OEG.sub.m+n-X with a second hydroxyl-terminated oligo (ethylene glycol) having (n) monomer subunits under conditions effective to displace said halo group to thereby form an oligo(ethylene glycol) having (m)+2(n) monomer subunits (OEG.sub.m+2n), wherein OEG.sub.m+2n possesses a primary or secondary hydroxyl group, wherein reacting the OEG.sub.m+n-X with the second hydroxyl-terminated oligo (ethylene glycol) comprises adding a 1:1 molar ratio of the OEG.sub.m+n-X to the second hydroxyl-terminated oligo (ethylene glycol) in a solution; converting said primary or secondary hydroxyl group into a halo group, --X, to form OEG.sub.m+2n-X; and reacting OEG.sub.m+2n-X with a third hydroxyl-terminated oligo (ethylene glycol) having (n) monomer subunits under conditions effective to displace said halo group to thereby form an oligo (ethylene glycol) having m+3n monomer subunits (OEG.sub.m+3n), wherein reacting the OEG.sub.m+2n-X with the third hydroxyl-terminated oligo (ethylene glycol) comprises adding a 1:1 molar ratio of the OEG.sub.m+2n-X to the third hydroxyl-terminated oligo (ethylene glycol) in a solution; wherein (m) and (n) each independently range from 1-10; and wherein (OEG.sub.m+3n) corresponds to the structure CH.sub.3O(CH.sub.2CH.sub.2O).sub.m+3nH, and is present as a monodisperse composition of CH.sub.3O(CH.sub.2CH.sub.2O).sub.m+3nH. 3. The method of claim 1, wherein (m) ranges from 1-3 and (n) ranges from 2-6. 4. The method of claim 2, wherein (m) ranges from 1-3 and (n) ranges from 2-6. 5. The method of claim 1, wherein each reacting step is carried out in the presence of a strong base. 6. The method of claim 2, wherein each reacting step is carried out in the presence of a strong base. 7. The method of claim 1, wherein each of the halo groups is Br. 8. The method of claim 2, wherein each of the halo groups is Br. |