A method for preparing dehydrodidemnin B compounds

Abstract

The invention discloses a method for preparing a dehydrodidemnin B compound, wherein the method comprises the following steps: subjecting the Didemnin B compound shown in formula I to an oxidant in an organic solvent for oxidation reaction to prepare the compound. The method has readily available raw materials, simple steps, rapidity and high efficiency, high yield, high purity, low cost, and is suitable for industrialized scale-up production.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of semi-synthetic raw materials of microbial origin, and in particular to a method for preparing a dehydrodidemnin B compound. Background Art

[0002] Dehydrodidemnin B, with a structural formula as shown in Formula 1, is a marine-derived first-in-class anticancer drug originally obtained from a protochordate, the Mediterranean sea squirt (Aplidiumalbicans). It can specifically bind to eukaryotic translation elongation factor 1A2 (eEF1A2) and target the protein's atypical effects, leading to tumor cell death through apoptosis (programmed cell death). Currently, dehydrodidemnin B has been approved for marketing for the treatment of relapsed or refractory multiple myeloma (MM) patients who have failed or are resistant to other therapies.

[0003]

[0004] At present, many syntheses and natural analogs of dehydrodidemnin B have been disclosed, including modifications of related side chains. However, the methods disclosed in the prior art generally have many operating steps, cumbersome processes, great difficulty, high costs, and are not suitable for industrial production. In summary, the processes of the prior art cannot meet the requirements for the efficient and large-scale preparation of dehydrodidemnin B compounds. Therefore, it is of great significance to develop a synthetic route and method that is suitable for industrial production, has simple steps, no safety and environmental protection pressure, and stable process. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a new preparation method of dehydrodidemnin B compounds.

[0006] A method for preparing a dehydrodidemnin B compound comprises the following steps:

[0007] The compound represented by formula I is subjected to oxidation reaction with an oxidant in an organic solvent to obtain a dehydrodidemnin B compound represented by formula II.

[0008]

[0009] Among them, R1~R 11 Each is independently hydrogen, halogen, unsubstituted or optionally substituted with one or more R 12 Substituted by the following groups: alkyl, cycloalkyl, alkoxy, heterocyclic, aryl, heteroaryl, arylalkyl, heteroarylalkyl, the R12 is selected from halogen, alkyl, alkyloxy, aryl, arylalkyl, heteroarylalkyl; or said R1 and the ortho-amino group together with the carbon atom to which they are connected form a substituted or unsubstituted 3-12-membered ring, said ring containing 0, 1 or 2 additional heteroatoms as one or more ring members, said heteroatoms being independently selected from nitrogen, oxygen or sulfur, and said ring may be mono- or poly-substituted by halogen, alkyl, cycloalkyl, alkoxy, heterocyclyl, aryl, heteroaryl.

[0010] According to an embodiment of the present invention, the R1 to R 11 Each is independently hydrogen, halogen, unsubstituted or optionally substituted with one or more R 12 Substituted with the following groups: C 1～20 Alkyl, C 3～20 Cycloalkyl, C 1～20 Alkoxy, 3-20 membered heterocyclic group, C 6～20 Aryl, 5-20 membered heteroaryl, C 6～20 Aryl-C 1～20 Alkyl, 5-20 membered heteroaryl-C 1～20 Alkyl, the R 12 Selected from halogen, C 1～20 Alkyl, C 1～20 Alkyloxy, C 6～20 Aryl, 5-20 membered heteroaryl-C 1～20 Alkyl, or said R1 and the ortho-amino group together with the carbon atom to which they are connected form a substituted or unsubstituted 3-12-membered ring, said ring containing 0, 1 or 2 additional heteroatoms as one or more ring members, said heteroatoms being independently selected from nitrogen, oxygen or sulfur, said ring being substituted by halogen, C 1～120 Alkyl, C 3～20 Cycloalkyl, C 1～20 Alkoxy, 3-20 membered heterocyclic group, C 6～20 Aryl or 5- to 20-membered heteroaryl is mono- or poly-substituted.

[0011] Further, according to an embodiment of the present invention, the R1 to R 11 Each is independently hydrogen, halogen, unsubstituted or optionally substituted with one or more R 12 Substituted with the following groups: C 1～12 Alkyl, C 3～12 Cycloalkyl, C 1～12 Alkoxy, 3-12 membered heterocyclic group, C 6～12 Aryl, 5- to 12-membered heteroaryl, C 6～12 Aryl-C 1～12 Alkyl, 5- to 12-membered heteroaryl-C 1～12 Alkyl, the R 12 Selected from halogen, C 1～12 Alkyl, C 1～12Alkyloxy, C 6～12 Aryl, C 6～12 Aryl-C 1～12 Alkyl, 5- to 12-membered heteroaryl-C 1～12 Alkyl, or said R1 and the ortho-amino group together with the carbon atom to which they are connected form a substituted or unsubstituted 3-8 membered ring, said ring containing 0, 1 or 2 additional heteroatoms as one or more ring members, said heteroatoms being independently selected from nitrogen, oxygen or sulfur, said ring being substituted by halogen, C 1～12 Alkyl, C 3～8 Cycloalkyl, C 1～12 Alkoxy, C 3～8 Heterocyclic group, C 6～12 The aryl group and the 5- to 12-membered heteroaryl group are mono- or poly-substituted.

[0012] Further, according to an embodiment of the present invention, the R1 to R 11 Each is independently hydrogen, halogen, unsubstituted or optionally substituted with one or more R 12 Substituted with the following groups: C 1～6 Alkyl, C 1～6 Alkoxy, C 6～12 Aryl, C 6～12 Aryl-C 1～6 Alkyl, the R 12 Selected from halogen, C 1～6 Alkyl, C 1～6 Alkoxy, C 6～12 Aryl, or said R1 and the ortho-amino group together with the carbon atom to which they are connected form a substituted or unsubstituted 3-8 membered ring, said ring containing 0, 1 or 2 additional heteroatoms as one or more ring members, said heteroatoms being independently selected from nitrogen, oxygen or sulfur, said ring being substituted by halogen, C 1～6 Alkyl, C 6～12 The aryl group is mono- or poly-substituted.

[0013] As an embodiment, the R1 and the ortho-amino group together with the carbon atom to which they are connected form a substituted or unsubstituted 3-12-membered ring, for example a 5-membered ring;

[0014] And / or said R2 is C 6～12 Aryl-C 1～6 Alkyl, wherein the aryl group is optionally replaced by C 1～6 Alkyl, C 1～6 The alkoxy group is mono-substituted or poly-substituted, preferably, R2 is p-methoxyphenylmethyl;

[0015] and / or said R3 is C 1～6 An alkyl group, such as a methyl group;

[0016] And / or said R4 is C 1～6An alkyl group, such as isobutyl;

[0017] and / or said R5 is C 1～6 An alkyl group, such as sec-butyl;

[0018] and / or said R6 is C 1～6 An alkyl group, such as isopropyl;

[0019] and / or said R7 is C 1～6 An alkyl group, such as a methyl group;

[0020] and / or said R8 is C 1～6 An alkyl group, such as isobutyl;

[0021] and / or R9 is C 1～6 An alkyl group, such as a methyl group;

[0022] and / or R 10 C 1～6 An alkyl group, such as a methyl group;

[0023] and / or R 11 C 1～6 An alkyl group, such as a methyl group.

[0024] As an embodiment, the compound of formula I is selected from the compound of formula I' (Didemnin B), and the compound of formula II is selected from the compound of formula II' (Dehydrodidemnin B)

[0025]

[0026] As an embodiment, the oxidant includes but is not limited to: the oxidant is selected from a chromium-based oxidant, a Dess-Martin oxidant, a swern oxidant, or a mixed oxidant of 2,2,6,6-tetramethylpiperidinyl oxide and an organic high-valent iodide or nitrate.

[0027] Preferably, the chromium-based oxidizing agent is selected from pyridinium chlorochromate (PCC), pyridinium dichromate (PDC), Jones reagent, and Collins reagent.

[0028] Preferably, the organic high-valent iodide is PhI(OAc)2.

[0029] Preferably, the nitrate is Fe(NO3)3·9H2O or Cu(NO3)2 3H2O.

[0030] As an embodiment, the oxidant is selected from pyridinium chlorochromate, pyridinium dichromate, Jones reagent, Collins reagent, Dess-Martin reagent, a mixture of TEMPO and Fe(NO3)3·9H2O, preferably pyridinium chlorochromate, pyridinium dichromate, Jones reagent or Collins reagent.

[0031] As an embodiment, the molar ratio of the oxidant to the compound represented by formula I is 1.0 to 3.0:1, for example, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2.0:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3.0:1.

[0032] As an embodiment, the organic solvent includes but is not limited to dichloromethane, acetone, tetrahydrofuran, ethyl acetate, acetonitrile, DMF or dioxane.

[0033] As an embodiment, the amount of the organic solvent added is 2.5-20 ml / g, preferably 10 ml / g, based on the mass of Didemnin B.

[0034] As an embodiment, the reaction temperature is 20-50°C, preferably 35-45°C, for example 35, 40, 45°C.

[0035] As an embodiment, the reaction time is 16 to 40 hours, preferably 16 to 20 hours, for example 16, 17, 18, 19, 20 hours.

[0036] As an embodiment, after the reaction is complete, the obtained reaction solution is concentrated to dryness, ethyl acetate is added, stirred and dissolved, and then filtered. The filtrate is washed with saturated brine, dried with anhydrous sodium sulfate, and filtered. The filtrate is concentrated to dryness to obtain a crude product, and the crude product is prepared by RP-Prep-HPLC to obtain a finished dehydrodidemnin B compound.

[0037] Furthermore, the reverse phase high performance liquid chromatography preparation process is: using C18, C8, C4 or C6H5 as the stationary phase and a mixed solvent of acetonitrile and water as the eluent, gradient elution is performed to obtain the finished dehydrodidemnin B compound.

[0038] Compared with the prior art, the present invention provides a method for preparing dehydrodidemnin B compounds by one-step reaction. The method has simple steps, is rapid and efficient, has high yield and purity, and is suitable for industrialized scale-up production. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is the HPLC chromatogram of Example 1;

[0040] Figure 2 is the HPLC chromatogram of the reaction solution of Example 6;

[0041] Figure 3 The HPLC chromatogram of the product of Example 6 is shown in FIG. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with specific examples, but the protection scope of the present invention is not limited thereto; the experimental methods in the examples of the present invention without specifying specific conditions are usually conventional conditions, or the conditions recommended by the raw material or commodity manufacturers. Reagents without specifying the source are usually conventional reagents available through commercial channels.

[0043] The starting material Didemnin B of the present invention was purchased from Zhejiang Hunda Biotechnology Co., Ltd.

[0044] Embodiment 1:

[0045] Didemnin B (22 mg, 0.02 mmol) and acetone (0.22 ml) were added to the reactor, stirred and dissolved, and PCC (10.8 mg, 0.05 mmol) was added. The temperature was raised to 40°C and the reaction was kept warm for 16 h. The reaction solution was sampled for testing (raw material conversion rate 96.9%, liquid phase purity 91.1%, HPLC chromatogram as shown in FIG. Figure 1 shown).

[0046] Embodiment 2:

[0047] Didemnin B (22 mg, 0.02 mmol) and tetrahydrofuran (0.22 ml) were added into the reactor, stirred to dissolve and then PCC (10.8 mg, 0.05 mmol) was added. The temperature was raised to 40°C and the reaction was kept warm for 20 h. The reaction liquid was sampled for detection (raw material conversion rate 98.6%, liquid phase purity 89.2%).

[0048] Embodiment 3:

[0049] Didemnin B (22 mg, 0.02 mmol) and ethyl acetate (0.22 ml) were added into the reactor, stirred to dissolve and then PCC (10.8 mg, 0.05 mmol) was added. The temperature was raised to 40°C and the reaction was kept warm for 17 h. The reaction liquid was sampled for detection (raw material conversion rate 99.4%, liquid phase purity 80.4%).

[0050] Embodiment 4:

[0051] Didemnin B (22 mg, 0.02 mmol) and acetone (0.22 ml) were added into the reactor, stirred until dissolved, and then PCC (10.8 mg, 0.05 mmol) was added. The mixture was reacted at 50° C. for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 97.0%, liquid phase purity 80.0%).

[0052] Embodiment 5:

[0053] Didemnin B (22 mg, 0.02 mmol) and dioxane (0.22 ml) were added into the reactor, and PCC (10.8 mg, 0.05 mmol) was added after stirring to dissolve. The mixture was reacted at 40° C. for 40 h, and the reaction solution was sampled for detection (raw material conversion rate 98.0%, liquid phase purity 75.2%).

[0054] Embodiment 6:

[0055] Didemnin B (2.2 g, 2 mmol) and acetone (22 ml) were added to a reaction flask, stirred and dissolved, and PCC (1.08 g, 5 mmol) was added. The reaction was carried out at 40°C for 16 h. The reaction solution was sampled for testing (raw material conversion rate 95.5%, liquid phase purity 86.5%, HPLC chromatogram as shown in Figure 2 The reaction solution was concentrated to dryness, ethyl acetate (22 ml) was added, stirred and dissolved, and then filtered. The filtrate was washed once with saturated brine and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated to dryness to obtain 2.43 g of crude Plitidepsin. The crude product was subjected to RP-Prep-HPLC (with 1010-C8 filler as the stationary phase and acetonitrile: water = 6:4 as the mobile phase for reverse preparation) to obtain 1.24 g of dehydrodidemnin B (liquid phase purity 98.90%, HPLC chromatogram as shown Figure 3 shown).

[0056] Embodiment 7:

[0057] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and PDC (84.6 mg, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 20 hours. The reaction liquid was sampled for detection (raw material conversion rate 93.3%, liquid phase purity 75.4%).

[0058] Embodiment 8:

[0059] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and PDC (42.3 mg, 0.113 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 24 hours. The reaction liquid was sampled for detection (raw material conversion rate 76.2%, liquid phase purity 65.3%).

[0060] Embodiment 9:

[0061] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and after stirring to dissolve, TEMPO (35 mg, 0.226 mmol) and iodophenyldiacetic acid (72.4 mg, 0.226 mmol) were added. The temperature was raised to 40°C, and the reaction was kept warm for 16 hours. The reaction liquid was sampled for detection (raw material conversion rate 99.84%, liquid phase purity 91%).

[0062] Embodiment 10:

[0063] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and Jones reagent (2 M, 113 μL, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 18 h. The reaction liquid was sampled for detection (raw material conversion rate 85.2%, liquid phase purity 68.5%).

[0064] Embodiment 11:

[0065] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and after stirring to dissolve, Collins reagent (1 M, 226 μL, 0.226 mmol) was added. After heating to 40°C, the reaction was kept warm for 20 h, and the reaction liquid was sampled for detection (raw material conversion rate 79.6%, liquid phase purity 63.5%).

[0066] Embodiment 12:

[0067] Didemnin B (22 mg, 0.02 mmol) and dichloromethane (1 ml) were added into the reactor, and after stirring to dissolve, Dess-Martin reagent (8.5 mg, 0.02 mmol) was added. The mixture was reacted at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 49.5%, liquid phase purity 10.2%).

[0068] Embodiment 13:

[0069] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and Dess-Martin (95.3 mg, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 16 h. The reaction liquid was sampled for detection (raw material conversion rate 99.8%, liquid phase purity 7.1%).

[0070] Embodiment 14:

[0071] Didemnin B (22 mg, 0.02 mmol) and dichloromethane (1 ml) were added into the reactor, stirred to dissolve, and then TEMPO (0.5 mg) and Fe(NO3)3·9H2O (1.5 mg) were added. The reaction was carried out at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 31.5%, liquid phase purity 29.3%).

[0072] Embodiment 15:

[0073] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, stirred and dissolved, and then TEMPO (35 mg, 0.226 mmol) and sodium hypochlorite solution (76.7 mg, effective chlorine concentration 10%, 0.226 mmol) were added. After the temperature was raised to 40°C, the reaction was kept warm for 16 hours, and the reaction liquid was sampled for detection (raw material conversion rate 17.63%, liquid phase purity 2.12%).

[0074] Embodiment 16:

[0075] Didemnin B (22 mg, 0.02 mmol) and dichloromethane (1 ml) were added into the reactor, and TEMPO (2.8 mg, 0.02 mmol) was added after stirring to dissolve. The mixture was reacted at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate: 5.3%, liquid phase purity: 0%).

[0076] Embodiment 17:

[0077] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and TEMPO (35 mg, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 16 h. The reaction liquid was sampled for detection (raw material conversion rate 6.1%, liquid phase purity 0%).

[0078] Embodiment 18:

[0079] Didemnin B (100 mg, 0.09 mmol) and dichloromethane (1 ml) were added into the reactor, and after stirring to dissolve, oxalyl chloride (14 mg, 0.11 mmol), DMSO (9 mg, 0.11 mmol), and triethylamine (36 mg, 0.36 mol) were added. After stirring in an ice-water bath for half an hour, the temperature was raised to room temperature and the reaction was carried out for 24 hours. The reaction solution was sampled for detection (raw material conversion rate 65%, liquid phase purity 36%).

[0080] Embodiment 19:

[0081] Didemnin B (22 mg, 0.02 mmol) and dichloromethane (1 ml) were added into the reactor, and after stirring to dissolve, dichlorodicyanobenzoquinone (4.54 mg, 0.02 mmol) was added. The mixture was reacted at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 7.3%, liquid phase purity 0%).

[0082] Embodiment 20:

[0083] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and dichlorodicyanobenzoquinone (51 mg, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 16 hours. The reaction liquid was sampled for detection (raw material conversion rate 6.6%, liquid phase purity 0%).

[0084] Embodiment 21:

[0085] Didemnin B (22 mg, 0.02 mmol) and dichloromethane (1 ml) were added into the reactor, and after stirring to dissolve, sulfur trioxide-pyridine mixture (3.18 mg, 0.02 mmol) was added. The mixture was reacted at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 10.6%, liquid phase purity 0%).

[0086] Embodiment 22:

[0087] Didemnin B (100 mg, 0.09 mmol) and acetone (1 ml) were added into the reactor, and sulfur trioxide-pyridine complex (36 mg, 0.226 mmol) was added after stirring to dissolve. The temperature was raised to 40°C, and the reaction was kept warm for 16 hours. The reaction liquid was sampled for detection (raw material conversion rate 7.6%, liquid phase purity 0%).

[0088] Embodiment 23:

[0089] Didemnin B (44 mg, 0.04 mmol) and acetone (0.44 ml) were added into the reactor, and after stirring to dissolve, hydrogen peroxide (11.21 mg, 0.1 mmol) was added. The mixture was reacted at room temperature for 16 h, and the reaction solution was sampled for detection (raw material conversion rate 24.1%, liquid phase purity 0%).

Claims

1. A method for preparing a dehydrodidemnin B compound, characterized in that: The following steps are involved: The compound represented by formula I is subjected to oxidation reaction with an oxidant in an organic solvent to obtain a dehydrodidemnin B compound represented by formula II. The compound of formula I is selected from the compound of formula I', and the compound of formula II is selected from the compound of formula II' The oxidant is selected from pyridinium chlorochromate, pyridinium dichromate, Jones reagent, and Collins reagent; the reaction temperature is 20-50° C., and the reaction time is 16-40 hours.

2. The preparation method according to claim 1, characterized in that: The molar ratio of the oxidant to the compound represented by formula I is 1.0-3.0:

1.

3. The preparation method according to claim 1, characterized in that: The organic solvent is selected from any one of dichloromethane, acetone, tetrahydrofuran, ethyl acetate, acetonitrile, N,N-dimethylformamide or dioxane; And / or, the amount of the organic solvent added is 2.5-20 ml / g based on the mass of the compound represented by formula I.

4. The preparation method according to claim 1, characterized in that: After the reaction is complete, the obtained reaction solution is concentrated to dryness, ethyl acetate is added, stirred and dissolved, and then filtered. The filtrate is washed with saturated brine, dried with anhydrous sodium sulfate, and filtered. The filtrate is concentrated to dryness to obtain a crude product. The crude product is subjected to reverse phase high performance liquid chromatography to obtain a finished product of dehydrodidemnin B compound; The reverse phase high performance liquid chromatography preparation process is: using C18, C8, C4 or C6H5 as the stationary phase and a mixed solvent of acetonitrile and water as the eluent, gradient elution is performed to obtain the finished dehydrodidemnin B compound.

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