WO2003096782A2 - Process for preparing maytansinol - Google Patents

Process for preparing maytansinol Download PDF

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Publication number
WO2003096782A2
WO2003096782A2 PCT/US2003/014759 US0314759W WO03096782A2 WO 2003096782 A2 WO2003096782 A2 WO 2003096782A2 US 0314759 W US0314759 W US 0314759W WO 03096782 A2 WO03096782 A2 WO 03096782A2
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Prior art keywords
maytansinol
cell
binding agent
maytansinoid
prepared
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PCT/US2003/014759
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French (fr)
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WO2003096782A3 (en
Inventor
Ann Marie Eldridge
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Smithkline Beecham Corporation
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Publication date
Application filed by Smithkline Beecham Corporation filed Critical Smithkline Beecham Corporation
Priority to AU2003228998A priority Critical patent/AU2003228998A1/en
Priority to EP03726777A priority patent/EP1507781A4/en
Priority to JP2004504795A priority patent/JP2005525423A/en
Priority to NZ536271A priority patent/NZ536271A/en
Priority to US10/513,682 priority patent/US20050152913A1/en
Publication of WO2003096782A2 publication Critical patent/WO2003096782A2/en
Publication of WO2003096782A3 publication Critical patent/WO2003096782A3/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D498/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms
    • C07D498/12—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms in which the condensed system contains three hetero rings
    • C07D498/18—Bridged systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6801—Drug-antibody or immunoglobulin conjugates defined by the pharmacologically or therapeutically active agent
    • A61K47/6803—Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates
    • A61K47/68033—Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates the drug being a maytansine
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P43/00—Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00

Definitions

  • the present invention relates to a process for preparing maytansinol from disulfide-containing maytansinoid esters.
  • Maytansinol is an expensive starting material and its precursor sources are limited to fermentation processes.
  • the reaction conditions used to produce maytansinoid esters produce roughly equal amounts of the desired stereoisomer, an undesired stereoisomer and unreacted maytansinol. Thus, it would be desirable to recover maytansinol from the undesired stereoisomer produced in the reaction for use in subsequent esterification reactions.
  • One aspect of the invention is processes for the preparation of maytansinol comprising reducing disulfide- containing may- ⁇ '"in ⁇ id esters with lithium aluminum hydride.
  • Another aspect of the invention is cell-binding agent/maytansinoi ⁇ complexes prepared from maytansinol produced by the processes of the invention.
  • the present invention provides a process for preparing maytansinol by reduction of the maytansinoid ester D-DMl-SMe (IV) with lithium aluminum hydride (iAlH4) .
  • D-DMl-SMe is an undesired isomer produced in the esterification of maytansinol by amino acid derivatives.
  • the recovered maytansinol can be recycled to produce more of the desired L- DMl-SMe isomer (III) .
  • the present invention also provides antibody/maytansinoid complexes prepared from maytansinol produced by the process of the invention.
  • Disulfide-containing maytansinoid esters useful for preparing the thiol-containing maytansinoid ester DM1 can be prepared by reacting the N-methyl-L-alanine derivative N- methyl-N- (3-methyldithiopropanoyl) -L-alanine (II) with maytansinol (I) in the presence of dicyclohexylcarbodiimide (DCC) and zinc chloride (ZnCl2> as shown in Scheme 1.
  • DCC dicyclohexylcarbodiimide
  • ZnCl2> zinc chloride
  • L-DMl-SMe is reduced with dithiothreitol (DTT) to produce DM1 (Scheme 2) which is useful for preparing immunocon ugate drugs.
  • the process of the invention comprises the step of reacting D-DMl-SMe (IV) with LiAlH4 in a reductive reaction as shown in Scheme 3.
  • the reaction is carried out in a water-miscible polar organic solvent.
  • the reaction temperature is about -5°C to about 10°C.
  • a solution of D-DMl-SMe (IV) in tetrahydrofuran (THF) at about 20°C is added to a THF solution of LiAlH 4 cooled to about -5°C
  • D-aminoacyl ester of maytansinol is prepared from maytansinol by esterification with disulfide- containing N-methyl-L-alanine derivatives such as Compound II, in the presence of DCC and ZnCl2 as disclosed in U.S.
  • L- and D-aminoacyl esters of maytansinol containing a disulfide-linking group are produced.
  • the stereoisomers are separated and D-DMl-SMe collected for use in the process of the invention.
  • LiAlH4 and THF can be purchased from chemical supply houses such as Aldrich Chemical Co. (St. Louis, MO).
  • the process of the invention can be used to make cell- binding agent/maytansanoid complexes by converting a compound of Formula I prepared by the process of the invention into the cell-binding agent/maytansinoid complex.
  • Compounds of Formula I produced by the process of the invention can be converted into a cell-binding agent/maytansinoid complex as described in U.S. Patent No. 5,208,020 to produce N-methyl-L- alanine containing maytansinoid derivatives.
  • These derivatives are then conjugated to cell-binding agents, preferably antibodies, via various linkers and are useful as tumor-activated pro-drugs.
  • the linkage is a disulfide link.
  • An exemplary cell-binding ager /maytansinoid complex can be prepared by a process comprising t , following steps: (a) esterifying maytansinol prepared by the process of claim 1 with a compound of Formula II to form a disulfide-containing maytansinoid ester; (b) reducing the disulfide-containing maytansinoid ester prepared by step (a) to a thiol-containing maytansinoid;
  • step (d) linking the thiol-containing maytansinoid produced by step (b) to the dithiopyridyl cell- binding agent of step (c) by a disulfide link.
  • the reaction mixture was cooled back to - 5°C and the progress of the reaction was monitored by high performance liquid chromotography (HPLC) . After 2h the reaction was complete, the HPLC assay showing maytansinol as the major product, 95.9% by peak area. The product matched the retention times of maytansinol in two different HPLC systems and had the desired molecular mass by LC/MS.
  • the reaction can be worked up by known standard techniques. See Reagents for Organic Synthesis. Volume 1, Feiser and Feiser, pp583-584, 1967.

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  • Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Veterinary Medicine (AREA)
  • Medicinal Chemistry (AREA)
  • Public Health (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Immunology (AREA)
  • Epidemiology (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Medicinal Preparation (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)

Abstract

Processes for preparing maytansinol from disulfide-containing maytansinoid esters by reduction with LiAlH4. The maytansinol is useful for preparing cell-binding agent/maytansinoid complexes.

Description

PROCESS FOR PREPARING MAYTANSINOL
Field of the Invention The present invention relates to a process for preparing maytansinol from disulfide-containing maytansinoid esters.
Background of the Invention Highly cytotoxic maytansinoid drugs and their therapeutic use have been described in U.S. Pat. No. 5,208,020. These drugs link cytotoxic maytansinoids to cell- binding agents such as antibodies and are useful as tumor- activated pro-drugs . These immunoconjugate drugs can be prepared from maytansinoid esters coupled to antibodies through a disulfide linkage. The maytansinoid esters are prepared from maytansinol and its ansamitocin precursors as described in U.S. Pat. No. 6,333,410. Ansamitocin production from Actinosynnema fermentation is described in PCT Publication No. WO01/77360 and U.S. Pat. Nos. 4,162,940; 4,228,239; 4,356,265; and 4,450,234.
Maytansinol is an expensive starting material and its precursor sources are limited to fermentation processes. The reaction conditions used to produce maytansinoid esters produce roughly equal amounts of the desired stereoisomer, an undesired stereoisomer and unreacted maytansinol. Thus, it would be desirable to recover maytansinol from the undesired stereoisomer produced in the reaction for use in subsequent esterification reactions.
Summary of the Invention
One aspect of the invention is processes for the preparation of maytansinol comprising reducing disulfide- containing may- τΛ'"in^id esters with lithium aluminum hydride.
Another aspect of the invention is cell-binding agent/maytansinoiα complexes prepared from maytansinol produced by the processes of the invention. Detailed Description of the Invention
All publications, including but not limited to patents and patent applications, cited in this specification are herein incorporated by reference as though fully set forth. The present invention provides a process for preparing maytansinol by reduction of the maytansinoid ester D-DMl-SMe (IV) with lithium aluminum hydride ( iAlH4) . D-DMl-SMe is an undesired isomer produced in the esterification of maytansinol by amino acid derivatives. The recovered maytansinol can be recycled to produce more of the desired L- DMl-SMe isomer (III) .
The present invention also provides antibody/maytansinoid complexes prepared from maytansinol produced by the process of the invention.
Disulfide-containing maytansinoid esters useful for preparing the thiol-containing maytansinoid ester DM1 can be prepared by reacting the N-methyl-L-alanine derivative N- methyl-N- (3-methyldithiopropanoyl) -L-alanine (II) with maytansinol (I) in the presence of dicyclohexylcarbodiimide (DCC) and zinc chloride (ZnCl2> as shown in Scheme 1. The reaction yields approximately equal amounts of the desired isomer -DMl-SMe (III), an undesired isomer R-DMl-SMe (IV) and unreacted maytansinol. The unreacted maytansinol is separated by chromatography from the mixture of isomers and the desired L-isomer is then separated from the R-isomer by a separate chromatography. L-DMl-SMe is reduced with dithiothreitol (DTT) to produce DM1 (Scheme 2) which is useful for preparing immunocon ugate drugs.
Figure imgf000004_0001
III
Figure imgf000004_0002
IV
Scheme 1
Figure imgf000005_0001
III
Scheme 2
The process of the invention comprises the step of reacting D-DMl-SMe (IV) with LiAlH4 in a reductive reaction as shown in Scheme 3. The reaction is carried out in a water-miscible polar organic solvent. Preferably, the reaction temperature is about -5°C to about 10°C. Most preferably, a solution of D-DMl-SMe (IV) in tetrahydrofuran (THF) at about 20°C is added to a THF solution of LiAlH4 cooled to about -5°C
Figure imgf000006_0001
IV I
Scheme 3
The D-aminoacyl ester of maytansinol, D-DMl-SMe (IV), is prepared from maytansinol by esterification with disulfide- containing N-methyl-L-alanine derivatives such as Compound II, in the presence of DCC and ZnCl2 as disclosed in U.S.
Pat. No. 6,333,410. L- and D-aminoacyl esters of maytansinol containing a disulfide-linking group are produced. The stereoisomers are separated and D-DMl-SMe collected for use in the process of the invention. LiAlH4 and THF can be purchased from chemical supply houses such as Aldrich Chemical Co. (St. Louis, MO).
The process of the invention can be used to make cell- binding agent/maytansanoid complexes by converting a compound of Formula I prepared by the process of the invention into the cell-binding agent/maytansinoid complex. Compounds of Formula I produced by the process of the invention can be converted into a cell-binding agent/maytansinoid complex as described in U.S. Patent No. 5,208,020 to produce N-methyl-L- alanine containing maytansinoid derivatives. These derivatives are then conjugated to cell-binding agents, preferably antibodies, via various linkers and are useful as tumor-activated pro-drugs. Preferably, the linkage is a disulfide link.
An exemplary cell-binding ager /maytansinoid complex can be prepared by a process comprising t , following steps: (a) esterifying maytansinol prepared by the process of claim 1 with a compound of Formula II to form a disulfide-containing maytansinoid ester; (b) reducing the disulfide-containing maytansinoid ester prepared by step (a) to a thiol-containing maytansinoid;
(c) introducing dithiopyridyl groups into a cell- binding agent; and
(d) linking the thiol-containing maytansinoid produced by step (b) to the dithiopyridyl cell- binding agent of step (c) by a disulfide link.
The present invention will now be described with reference to the following specific, non-limiting example.
EXAMPLE Preparation of Maytansinol from D-DMl-SMe
All reagents utilized herein were sourced as first described below.
A 15 mL septum-capped vial, equipped with a magnetic stirrring bar, was charged with lithium aluminum hydride (IM in THF, 0.52 mL, 5.19x10"" mole, 4.2 equiv, Aldrich Chemical Co., St. Louis, MO) and the solution cooled to -5°C. A solution of N-methyl-N- (3-methyldithiopropanoyl) -D- alanylmaytansine (100 mg, 1.28 x 10 "4 mole, 1 equiv, ChemSyn Laboratories, Lenexa, KS) in anhydrous THF (5 mL, Aldrich Chemical Co . ) was added at such a rate that the temperature did not exceed 8°C. The reaction mixture was cooled back to - 5°C and the progress of the reaction was monitored by high performance liquid chromotography (HPLC) . After 2h the reaction was complete, the HPLC assay showing maytansinol as the major product, 95.9% by peak area. The product matched the retention times of maytansinol in two different HPLC systems and had the desired molecular mass by LC/MS. The reaction can be worked up by known standard techniques. See Reagents for Organic Synthesis. Volume 1, Feiser and Feiser, pp583-584, 1967.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.

Claims

(1) A process for the preparation of maytansinol comprising reducing D-DMl-SMe with lithium aluminum hydride.
(2) The process of claim 1 wherein D-DMl-SMe is added to at least about 4 equivalents of lithium aluminum hydride.
(3) The process of claim 1 wherein the lithium aluminium hydride is in tetrahydrofuran (THF) .
(4) The process of claim 4 wherein the reaction temperature is at about -5°C to about 10°C.
(5) The process of claim 1 wherein about 96% of D-DM1- SMe is converted to maytansinol.
(6) Maytansinol prepared by the process of claim 1.
(7) A cell-binding agent/maytansinoid complex prepared by converting maytansinol prepared by the process of claim 1 into the cell-binding agent/maytansinoid complex.
(8) The cell-binding agent/maytansinoid complex of claim 7 wherein the cell-binding agent is an antibody.
(9) A cell-binding agent/maytansinoid complex prepared by a process comprising the following steps:
(a) esterifying maytansinol prepared by the process of claim 1 with a compound of Formula II to form a disulfide-containing maytansinoid ester;
(b) reducing the disulfide-containing maytansinoid ester prepared by step (a) to a thiol-containing maytansinoid;
(c) introducing dithiopyridyl groups into a cell- binding agent ; and
(d) linking the thiol-containing maytansinoid produced by step (b) to the dithiopyridyl cell- binding agent of step (c) by a disulfide link.
(10) The cell-binding agent/maytansinoid complex of claim 8 wherein the cell-binding agent is an antibody.
PCT/US2003/014759 2002-05-13 2003-05-12 Process for preparing maytansinol WO2003096782A2 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AU2003228998A AU2003228998A1 (en) 2002-05-13 2003-05-12 Process for preparing maytansinol
EP03726777A EP1507781A4 (en) 2002-05-13 2003-05-12 Process for preparing maytansinol
JP2004504795A JP2005525423A (en) 2002-05-13 2003-05-12 Method for preparing maytansinol
NZ536271A NZ536271A (en) 2002-05-13 2003-05-12 Process for preparing maytansinol
US10/513,682 US20050152913A1 (en) 2002-05-13 2003-05-12 Process for preapring maytansinol

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US37997602P 2002-05-13 2002-05-13
US60/379,976 2002-05-13

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NZ (1) NZ536271A (en)
WO (1) WO2003096782A2 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006062779A2 (en) 2004-12-09 2006-06-15 Centocor, Inc. Anti-integrin immunoconjugates, methods and uses
EP1945647A2 (en) * 2005-11-08 2008-07-23 Immunogen, Inc. Processes for preparation of maytansinol
WO2020033851A1 (en) 2018-08-09 2020-02-13 Notable Labs, Inc. Compositions comprising priming agents and their use in the treatment of cancer
KR20210135545A (en) * 2019-03-01 2021-11-15 셀진 코포레이션 Preparation of Maytansinol

Families Citing this family (6)

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Publication number Priority date Publication date Assignee Title
US7589180B2 (en) 2001-05-11 2009-09-15 Abbott Laboratories Inc. Specific binding proteins and uses thereof
US20100056762A1 (en) 2001-05-11 2010-03-04 Old Lloyd J Specific binding proteins and uses thereof
CN104013956B (en) 2007-01-25 2018-12-18 达娜-法勃肿瘤研究所公司 Purposes of the anti-egfr antibodies in the mutant mediated disease for the treatment of EGFR
AU2008227123B2 (en) 2007-03-15 2014-03-27 Ludwig Institute For Cancer Research Ltd. Treatment method using EGFR antibodies and src inhibitors and related formulations
CA2696360C (en) 2007-08-14 2018-11-20 Ludwig Institute For Cancer Research Monoclonal antibody targeting the egfr receptor and uses thereof
WO2011100403A1 (en) 2010-02-10 2011-08-18 Immunogen, Inc Cd20 antibodies and uses thereof

Citations (1)

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WO2002074775A1 (en) * 2001-03-16 2002-09-26 Smithkline Beecham Corporation Process for preparing maytansinol

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US4162940A (en) * 1977-03-31 1979-07-31 Takeda Chemical Industries, Ltd. Method for producing Antibiotic C-15003 by culturing nocardia
CA2026147C (en) * 1989-10-25 2006-02-07 Ravi J. Chari Cytotoxic agents comprising maytansinoids and their therapeutic use
US5208020A (en) * 1989-10-25 1993-05-04 Immunogen Inc. Cytotoxic agents comprising maytansinoids and their therapeutic use
US6333410B1 (en) * 2000-08-18 2001-12-25 Immunogen, Inc. Process for the preparation and purification of thiol-containing maytansinoids

Patent Citations (1)

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WO2002074775A1 (en) * 2001-03-16 2002-09-26 Smithkline Beecham Corporation Process for preparing maytansinol

Non-Patent Citations (1)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006062779A2 (en) 2004-12-09 2006-06-15 Centocor, Inc. Anti-integrin immunoconjugates, methods and uses
EP1945647A2 (en) * 2005-11-08 2008-07-23 Immunogen, Inc. Processes for preparation of maytansinol
JP2009514978A (en) * 2005-11-08 2009-04-09 イミュノジェン・インコーポレーテッド Preparation method of maytansinol
EP1945647A4 (en) * 2005-11-08 2010-10-20 Immunogen Inc Processes for preparation of maytansinol
WO2020033851A1 (en) 2018-08-09 2020-02-13 Notable Labs, Inc. Compositions comprising priming agents and their use in the treatment of cancer
KR20210135545A (en) * 2019-03-01 2021-11-15 셀진 코포레이션 Preparation of Maytansinol
KR102667230B1 (en) 2019-03-01 2024-05-21 셀진 코포레이션 Preparation of mytansinol

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AU2003228998A1 (en) 2003-12-02
US20050152913A1 (en) 2005-07-14
WO2003096782A3 (en) 2004-03-11
EP1507781A4 (en) 2006-03-15
EP1507781A2 (en) 2005-02-23
NZ536271A (en) 2008-01-31
JP2005525423A (en) 2005-08-25

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