Processes for preparing peptide conjugates and linkers

Patent metadata

Field	Value
Publication number	US-9352050-B2
Application number	US-201214367216-A
Country	US
Kind code	B2
Filing date	Dec 10, 2012
Priority date	Dec 20, 2011
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

The present invention provides a process for preparing a compound of Formula 5b, as well as intermediates thereof, and novel classes of compounds useful in process for preparing these and similar compounds.

First claim

The invention claimed is:

1. A process for preparing a compound according to formula 5a

comprising
(i) reacting 9a and 11 together in the presence of 1-propanephosphonic acid anhydride (T3P) to create compound 13a

(ii) catalytic hydrogenation with Pd/C of compound 13a in a THF:H 2 O solution of at least about 50% THF to produce a compound of formula 4a

(iii) combining a solution of 14a in THF with a compound according to formula 15 in a reaction substantially free of base to produce compound 6a

(iv) reacting a compound according to the formula 6a with a compound according to formula 19a in THF in the presence of DCC to produce compound 20a

(v) combining 20a with a ε-amino containing peptide 2 dissolved in an aprotic polar 15th solvent to produce compound 3a

(vi) dissolving compound 3a in DMSO;
(vii) adding histidine buffer at pH between about 5.5 to about 7.5 to the solution of DMSO and 3a of step (vi);
(viii) Adding an antibody comprising a variable light region comprising SEQ ID NO:5 and a variable heavy region comprising SEQ ID NO:6 to the solution of step (vii), so as to have a peptide:antibody molar ratio of between about 1.8:1 to about 3:1;
(ix) Agitating the mixture formed in step (viii) at a medium speed so as to avoid foaming the reaction mixture for at least about 1 hr at between about pH 5.5 and about pH7.5 and at a temperature of between about 5° C. and 35° C.; and
(x) Filtration of the solution from (ix) to extract the resultant peptide-linker antibody conjugate 5a

wherein q=1, 2, 3, 4, or 5, X=F or Cl, and m=3, 4, or 5.

2. The process as claimed in claim 1 , further comprising a process for preparing a compound according to Formula 3a

comprising
(i) reacting 9a and 11 together in the presence of 1-propanephosphonic acid anhydride (T3P) to create compound 13a

(ii) catalytic hydrogenation with Pd/C of compound 13a in a THF:H 2 O solution of at least about 50% THF to produce a compound of formula 14a

(iii) combining a solution of 14a in THF with a compound according to formula 15 in a reaction substantially free of base to produce compound 6a

(iv) reacting a compound according to the formula 6a with a compound according to formula 19a in THF in the presence of DCC to produce compound 20a

(v) combining 20a with a ε-amino containing peptide 2 dissolved in an aprotic polar 15th solvent to produce bioconjugate 3b

wherein q=1, 2, 3, 4, or 5, X=F or Cl, and m=3, 4, or 5.

3. The process as claimed in claim 1 , further comprising a process for preparing a compound of formula 13a

wherein q is 1, 2, 3, 4, or 5, characterized in that

are reacted together in the presence of 1-propanephosphonic acid anhydride (T3P).

4. The process as claimed claims 1 , wherein the reaction between 9a and 11 is carried out in the presence of a 1 st solvent selected from the group consisting of of tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), 1-methyl-2-pyrrolidinone, ethyl acetate (EtOAc), and acetonitrile (MeCN), and preferably MeCN.

5. The process as claimed in claim 4 , wherein the reaction is carried out in the presence of a 1 st base selected from the group consisting of trimethylamine, triethylamine, tributylamine, DIPEA, pyridine, DBU, DABCO, 2,3-lutidine, 2,4-lutidine, 2,5-lutidine, 2,6-lutidine, 3,4-lutidine, 3,5-lutidine, and preferably DIPEA.

6. The process as claimed in claim 1 , further comprising a_process for preparing a compound of formula 4a,

wherein q is 1, 2, 3, 4, or 5, comprising catalytic hydrogenation with Pd/C of compound 13a,

and characterized in that the reaction is conducted in a THF:H 2 O solution of at least about 50% THF.

7. The process as claimed in claim 1 , wherein the THF:H 2 O solution comprises THF in an amount selected from the group consisting of at least about 60%, at least about 70%, at least about 80%, and at least about 90%.

8. The process as claimed in claim 1 , wherein prior to hydrogenation in THF/H 2 O, compound 13a is subjected to treatment with activated charcoal.

9. The process as claimed in claim 8 , wherein the activated charcoal is selected from the group consisting of SX-Plus, Darco® S-51HF, E Supra USP, SX-Ultra, CASP, Darco® G-60 and CGSP.

10. The process as claimed in claim 1 , further comprising a process for preparing a compound of formula 6a

wherein q=1, 2, 3, 4 or 5; comprising reacting a solution of compound 14a

in a 6 th solvent comprising THF, with compound 15

and characterized in that the reaction is carried out substantially free of a base.

11. The process as claimed in claim 1 , wherein the compound 14a is reacted with between about 1 and about 10 equivalents of compound 15.

12. The process as claimed in claim 1 , wherein the solution of compound 6a is distilled under vacuum, following which a 7 th solvent comprising C 1 -C 4 alkyl acetate is added to attain a solvent composition of between about 25%THF/75% C 1 -C 4 alkyl acetate and about 100% C 1 -C 4 alkyl acetate.

13. The process as claimed in claim 12 , wherein the 7 th solvent is selected from the group consisting of methyl acetate, ethyl acetate, i-propyl acetate, n-propyl acetate, n-butyl acetate, and preferably is i-propyl acetate.

14. The process as claimed in claim 12 , wherein the ratio between 6 th and 7 th solvents is between 25:75 and 0:100.

15. The process as claimed in claim 1 , further comprising a process for crystallization of a compound according to the formula 6a, com

Assignees

• Pfizer

Inventors

• Magano Javier
• Maloney Mark Thomas
• Marcq Olivier J
• Nadkarni Durgesh Vasant
• Pozzo Mark John
• Teixeira Jr John Joseph

Classifications

• C07D205/08 Primary

  with one oxygen atom directly attached in position 2, e.g. beta-lactams · CPC title

• A61K39/395

  Antibodies (agglutinins A61K38/36 {; as drug carriers A61K47/50}); Immunoglobulins; Immune serum, e.g. antilymphocytic serum · CPC title

• A61K47/6835

  the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site · CPC title

• A61P35/00

  Antineoplastic agents · CPC title

• A61K47/50

  the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates · CPC title