HUT72646A - Novel beta-lactams, methods for the preparation of taxanes, and sidechain-bearing taxanes - Google Patents

Abstract

The present invention relates to a side chain taxane derivative represented by the general formula (VII) wherein R1 and R2 (i) are the same alkyl groups, or (ii) together form a cycloalkyl group, or (iii) together form a cycloalkenyl group, or (iv) together a heterocyclic group. form; R3 is alkyl; R4 is aryl; R3 is hydrogen, arylcarbonyl or alkoxycarbonyl; and T for the preparation of the 13-linked taxane moiety and its salts by reaction of a β-lactam of formula (I) with a suitable taxane derivative of formula (VIII) in a C-13 position in a C-13 moiety. 1

Description

A process for the preparation of side chain taxane derivatives using novel β-lactams

BRISTOL-MYERS SQUIBB COMPANY, PRINCETON, New Jersey, US

inventors:

THOTTATHIL John K., ROBBINSVILLE, New Jersey, US

TRIFUNOVICH Ivan D., BÉLLÉ MEAD, New Jersey, US

KUCERA David J., WARREN, New Jersey, US

LI Wen-Sen, LINCROFT, New Jersey, US

Date of filing: March 18, 1994

priority:

March 19, 1993. (033,598) US

The present invention relates to a novel process for the preparation of side chain-bearing taxanes, which comprises forming a side chain by coupling with a β-lactam.

Taxane derivatives are diterpenes used in the pharmaceutical industry. For example, one of the derivatives of taxane, taxol of formula A, wherein Ph is phenyl, Ac is acetyl, and Bz is benzoyl, has been shown to be an effective anticancer agent.

Naturally occurring taxane derivatives, such as taxol, are found in plant materials and can be isolated from them. However, these taxane derivatives are often present in very small amounts in plant material and, for example, in the case of taxol, slow growing yew, one of the sources of the compound, would be very much needed. Therefore, research is continuing in the art to synthesize naturally occurring taxane derivatives, such as taxol, and to prepare pharmaceutically usable analogs of such compounds.

Taxane derivatives are diterpenes containing the taxane moiety of formula (B). Of particular interest are taxane derivatives in which the taxane moiety has 11 and 12 double-bonded sites and contains a side chain at position 13, such as taxol. Pharmacologically active taxane derivatives such as taxol may be used as antitumor agents in the treatment of patients with breast, ovarian, colon or lung cancer, melanoma or leukemia.

More specifically, the present invention relates to a novel process.

- taxane derivatives of the formula (VII) bearing 3 chains of formula wherein:

^R1 and ^R2 (i) both the same alkyl, or (ii) together form a cycloalkyl group, or (iii) together form a cycloalkenyl group, or (iv) together form a heterocyclic group;

R ² is alkyl;

R ⁴ is aryl; and r5 is hydrogen, arylcarbonyl or alkoxycarbonyl; and

T is a taxane moiety directly attached to the 13-position, and salts thereof, which is a process for preparing a β-lactam of formula (I) or a salt thereof with a taxane derivative of formula (VIII) in the presence of a coupling reagent wherein T is a reaction of the above - or a salt thereof, and optionally converting the -OC (R ⁴ ) (R ² ) (OR ³ ) group in the side chain of the resulting compound of formula VII to a hydroxy group; reaction with a taxane derivative or a salt thereof.

Addition of a side chain as described above may itself enhance or enhance the pharmacological activity of the taxane compound or provide a taxane derivative which is more readily converted to a taxane derivative having a greater or more favorable pharmacological activity than the parent compound.

The β-lactams of the formula (I) - in which

R ^1, R ^2, R ^2, R ⁴ e _and R 5 are as defined in formula (VII): - carrier preferably used sidechain taxane derivatives - e.g. taxol and derivatives thereof - the preparation. More specifically, the side chain may be formed by coupling these compounds to a taxane moiety.

Because the stereochemical form of the taxane derivatives may affect their therapeutic effect, it is desirable to employ β-lactam intermediates that will yield the desired taxane derivative in the stereochemically desired configuration. In the β-lactams of the formula I, the carbon atom marked with an asterisk is not asymmetric. If such a central carbon atom is asymmetric, the β-lactams of the diastereomers will have better results than the β-lactams containing asymmetric carbon at the asterisk because of higher yields, since it is easier to purify the taxane product after obtaining a mixture of compounds of different stereochemical configurations.

Some side-chain taxane derivatives of the present invention are described, for example, in U.S. Patent Nos. 400,971, 4,876,470, 4,924,012 and 4,924,011. Preferably, the taxotere of formula (C), or more preferably, the taxol, is prepared as a compound of formula (IX).

As used herein, the term alkyl or alk, alone or as part of another group, is an optionally substituted straight or branched chain saturated hydrocarbon group preferably having from 1 to 10 carbon atoms in the normal chain, such as methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, pentyl, hexyl, isohexyl, heptyl, 4,4-dimethylphenyl, octyl,

2,2,4-trimethylpentyl, nonyl, decyl, undecyl, dodecyl and the like. The substituents may be, for example, one or more halogen atoms, alkoxy, alkylthio, alkenyl, alkynyl, aryl, cycloalkyl, cycloalkenyl, hydroxy or protected hydroxy, carboxy, alkoxycarbonyl, alkylcarbonyl oxy, carbamoyl, amino, mono- or dialkylamino or mercapto.

The term lower alkyl or lower alkyl refers to the above optionally substituted alkyl group having from 1 to 4 carbon atoms in the normal chain.

The term alkoxy and alkylthio means an alkyl group as described above which is bonded through an oxygen or sulfur bridge [(-O-) or (-S-)]. Alkoxycarbonyl means an alkoxy group bonded through a carbonyl group. Alkylcarbonyloxy means an alkyl group which is bonded through a carbonyl group bonded through an oxygen bridge. Monoalkylamino and dialkylamino are amino groups substituted with one or two of the above alkyl groups.

The term alkenyl, alone or as part of another group, means an optionally substituted above alkyl group containing at least one carbon-carbon double bond. The substituent may be one or more of the above alkyl groups or one or more of the substituents mentioned above as possible substituents on the alkyl groups.

The term alkynyl, alone or as part of another group, means an optionally substituted above alkyl group containing at least one carbon-carbon triple bond. The substituent may be one or more of the above alkyl groups or one or more of the substituents mentioned above as possible substituents on the alkyl groups.

The term cycloalkyl, alone or as part of another group, means an optionally substituted saturated cyclic hydrocarbon, preferably having from 1 to 3 rings and from 3 to 7 carbon atoms in each. Examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, cyclododecyl and adamantyl. These substituents may be one or more of the above alkyl groups, or one or more of the above substituents as alkyl substituents.

The term cycloalkenyl, used alone or as part of another group, means an optionally substituted group such as the above cycloalkyl groups, except that it also contains at least one carbon-carbon double bond which renders the ring partially unsaturated. The substituent may be one or more of the above alkyl groups or one or more of the substituents mentioned above as possible substituents on alkyl groups.

The term ar or aryl, used alone or as part of another group, means an optionally substituted homocyclic aromatic group, preferably having 1 to 2 rings and 6 to 12 carbon atoms. Examples of such unsubstituted groups include phenyl, biphenyl and naphthyl. The substituent may be one or more nitro groups, preferably up to three, or as defined above as alkyl or as a possible substituent on alkyl groups.

The term arylcarbonyl, used alone or as part of another group, means an aryl group, as described above, which is attached on a carbonyl group.

The term heterocyclo or heterocyclic, used alone or as part of another group, means an optionally substituted, fully saturated or unsaturated, aromatic or non-aromatic cyclic group having at least one heteroatom in at least one ring. These groups preferably contain one or two 5- or 6-membered rings. The heterocyclic ring may contain, for example, 1 or 2 oxygen atoms, 1 or 2 sulfur atoms, and / or 1 to 4 nitrogen atoms. The heterocycles may be attached via any carbon or heteroatom in the ring system. Examples of such heterocyclic groups include thienyl, furyl, pyrrolyl, pyridyl, imidazolyl, pyrrolidinyl, piperidinyl, azepinyl, indolyl, isoindolyl, quinolyl, isoquinolyl, benzothiazolyl, benzoxazolyl, benzimidazole. benzoxadiazolyl, benzofurazanyl, preferably tetrahydropyranyl (e.g. 4-tetrahydropyranyl). The substituent may be one or more of the above alkyl groups or one or more of the substituents mentioned above as possible substituents on alkyl groups.

The term halogen or halo, alone or as part of another group, refers to chlorine, bromine, fluorine or iodine.

The taxane moiety having the skeletal structure represented by formula (B) may be substituted and may have a double bond in its ring system.

The term taxane refers to a compound comprising a taxane moiety as described above. The side-chained taxane derivative is a compound comprising a taxane moiety as defined above and, in addition, a side chain that binds to the C-13 site. A protecting group for a hydroxy group may be any group which is capable of protecting a free hydroxy group and may be removed after the reaction to which it is applied without damaging the remainder of the molecule. Such groups and their synthesis are described in T.W. Greene, Protective Groups in Organic Synthesis (John Wiley and Sons (1981)), or Fieser & Fieser. Examples of protecting groups for hydroxy include methoxymethyl, 1-ethoxyethyl, 1-methyl-1-methoxyethyl, benzyloxy-methyl, [β- (trimethylsilyl) ethoxy] methyl. -, tetrahydropyranyl, (2,2,2-trichloroethoxy) carbonyl, tert-butyl, diphenylsilyl, trialkylsilyl, (trichloromethoxy) carbonyl or (2,2,2-trichloro) ethoxy) methyl group.

The term salt includes salts formed with organic and / or inorganic acids and / or bases.

The alkali metal silylamide base is a base containing a group of formula (a) wherein M is an alkali metal such as lithium, sodium or potassium.

The preparation of β-lactams of the formula I is a

Ρ 94 00803, incorporated herein by reference.

Examples of compounds of formula (VIII) wherein the hydroxy group is directly attached to the C-13 site and are useful in the process of the present invention are found in the aforementioned literature, in particular in European Patent Application No. 400,971. Most preferred of the compounds of formula (VIII) is the compound of formula (X): wherein

R ⁷ is hydrogen, alkylcarbonyl, or a hydroxy protecting group such as acetyl; and r8 is hydrogen or hydroxy, and particularly preferred are the 7-O-trialkylsilyl (baccatin III) derivatives, such as 7-O-triethylsilyl-baccatin III or 7-O- ( trimethylsilyl) baccatin III. 7-O- (triethylsilyl) (baccatin III) can be prepared, for example, from 10-deacetyl (baccatin III) according to Denis et al., J. Am. Chem. Soc.

5917 (1988) 1. Preferably, 7-O-triethylsilyl (baccatin III) is prepared as described in the Examples below. Finally, if, for example, R ⁷ is hydrogen, the compound of formula (X) may be acylated in situ prior to the side chain linkage.

The coupling reagent used in the process of the present invention may be any compound which facilitates the coupling reaction to form a side-chain taxane derivative of formula (VII), such as tertiary amines such as triethylamine, diisopropylethylamine, pyridine , N-methylimidazole, 4- (dimethylamino) pyridine (DMAP) or metal-containing bases which form metal alkoxides at the C-13 position of the taxane derivative of formula VII, such as lithium diisopropylamide ( LDA), unsubstituted low carbon lithium compounds or phenyl lithium.

Preferably, the coupling reagent used in the process of the invention is an alkali metal silyl amide base or a spherically inhibited alkali metal amide base. Such bases can be described by the general formula (XI), wherein R.9 and ^R10 are trialkylsilyl or cycloalkyl, or together with the nitrogen to which they are bonded, form a heterocyclic group; and

M is a brain alkali metal such as lithium, sodium or potassium.

As the base, particularly those which are alkali metal silylamides of formula (XI), are those which are soluble in the reaction medium used, more preferably an alkali metal hexamethyldisilazide (where R 1 and R 10 are trimethylsilyl and M is sodium, lithium or potassium), most preferably lithium hexamethyldisilazide. Spherically inhibited alkali metal amide bases include those having -Ν (M) -, where M is as defined above, and which are substantially the same or more spatially coupled when coupling β-lactam with a taxane containing a hydroxy group at C-13. inhibitors such as lithium hexamethyldisilazide. Examples of such spherically inhibited bases are alkali metal tetramethylpiperidides and alkali metal dicyclohexamides.

The use of the above alkali metal bases, in particular the silyl amide bases, used in the process of the invention is advantageous, firstly, because they are not highly nucleophilic bases, so that the taxane derivative (VIII) used as the starting material has minimal or no degradation. on the other hand, they yield a high yield (preferably about 90% or greater) and a high purity (preferably about 98% or higher). The present invention therefore relates to a process for the coupling of a taxane derivative of formula VIII with any β-lactam of formula I which is capable of forming a side chain at the C-13 site of the taxane derivative, wherein the coupling agent is an alkali metal silylamide. or a spherically inhibited metal amide base.

The above coupling reaction of the present invention is preferably conducted at a temperature of about -70 to about 25 ° C and at atmospheric pressure.

The reaction time can range from about half an hour to about four hours and is preferably carried out under an inert gas such as argon.

The molar ratio of the taxane derivative (VIII) to the β-lactam (I) used as starting material is preferably greater than about 1: 1.16, more preferably about 1: 1 to about 1: 1.3, most preferably about 1: 1.2. The molar ratio of the taxane derivative of general formula VIII used as starting material to an alkali metal base such as silylamide base is preferably about 1: 1.1 to about 1: 1.5, most preferably about 1: 1, first

The organic solvent is preferably a reaction inert solvent. Particularly preferred solvents are tetrahydrofuran, toluene and diethyl ether. Preferably, the solvent is used in an amount such that the taxane derivative (VIII) used as starting material and the solvent to weight ratio: about 1: 5 to about 1: 2.5.

In the process of the present invention, the side-chain-bearing taxane derivative of formula (VII) is optionally converted to its -OCR- ¹ -) (R ² ) (OR ³ ) group. These groups are optionally converted after or together with other hydroxy groups, such as in the taxane moiety, by suitable methods, for example, by reacting the compound with an acid such as an inorganic acid such as hydrochloric acid or hydrogen fluoride or an organic acid such as acetic acid.

The deprotection is preferably carried out at a temperature of about -30 ° C to about 60 ° C and at atmospheric pressure. The reaction time is from about 2 hours to about 72 hours and is preferably carried out under an inert gas such as argon.

The molar ratio of acid deprotection to taxane derivative is preferably from about 1: 1 to about 20: 1 (v / v). Preferably, the organic solvent is the reaction-inert solvent. A particularly preferred solvent is a mixture of ethanol and tetrahydrofuran and a mixture of acetonitrile, acetone and water. Preferably, the solvent is used in an amount such that the weight ratio by volume of the taxane derivative to the solvent mixture (preferably tetrahydrofuran: ethanol or hydrochloric acid / water) is about 1:10 to about 1:50, more preferably 1:30.

The present invention also relates to the side chain horA taxol, and may conveniently be carried out, for example, in the presence of 7-O-trialkylsilyl (bactin III) as (VIII) potassium silylamide base ( 3R-cis) -l-benzoyl-3

- (1-Methyl-1-methoxyethoxy) -4-phenyl-2-azetidinone as β-lactam. After formation of the side chain, the triethylsilyloxy and 1-methyl-1-methoxyethoxy groups can be converted to the hydroxy groups by the methods described above to obtain the taxol.

Salts or solvates, such as hydrates, of the reagents or products may be used or prepared in any of the methods of the invention.

As can be seen, the above taxane derivatives and β-lactams can exist in several stereoisomeric forms. The invention encompasses all stereoisomers of the above compounds, either alone (i.e. practically free of other isomers), or with other selected isomers (e.g. in the form of a racemate) or with all stereoisomers. Preferably the compounds are substantially free of other isomers, i.e. pure enantiomers.

Preferred stereochemically configurations are those compounds of formula I wherein the -OC (R ⁴ ) (R 4) (OR 4) and R ⁴ groups are in the cis position, as shown in formula (I '), if the absolute configuration of the compound of formula (I) is the same as that of (3R-cis) -1-benzoyl-4-phenyl-3- (1-methyl-1-methoxyethoxy) -2-azetidinone.

The configuration of the side chain attached to the C-13 carbon atom of the compounds of formulas VII and IX preferably corresponds to the configuration of the above cis-L-lactams as shown in the formulas VIIa and IXa, where the absolute configuration of the side chains is the same. taxoléval.

The following examples are intended to illustrate the invention in more detail and are not intended to limit the scope of the invention in any way.

Example 1 {[2aR- (2aa, 45, 4aS, 65, 9α, 11α, 12α, 12aa, 12ba) 1-6,12b-bis-Acetoxy-12 - (benzoyloxy) -2a, 3,4, 4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-4 - [(triethylsilyl) oxy] -11-hydroxy-4a, 8,13,13-tetramethyl-5-oxo- 7,11-Methano-1H-cyclodeca- [3,41-benzo [1,2-b] xxet-9-yl] - (2R *, 3S *) - 3- (benzoylamino) -3-phenyl-2- (1- Preparation of methyl 1-methoxyethoxy) propionate (Compound 5)

In the drawings and description, Ac is acetyl, Bz is benzoyl, TES is triethylsilyl, and MOP is 1-methyl-1-methoxyethyl.

(a) 7-TES- (baccatin III) Γ (4a2) Old (i) {[2aR- (2aa, 45, 65, 9a, 115,12a, 12aa, 12ba)] -12b-Acetoxy-2a, 3 , 4,4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-6,9,11-trihydroxy-4a, 8,13,13-tetramethyl-5-oxo-4 - [(triethylsilyl -silyl) oxy] -7,11-methano-1H-cyclodeca- [3,4] benz [1,2-b] oxet-12-yl} benzoate [7-O-TES- (10-deacetyl) baccatin III), 4al 1 In a 1 liter 3-necked flask equipped with a mechanical stirrer and a digital thermometer, flame-dried and purged with argon, 27.4 g (50.3 mmol) of 10-deacetylbaccatin III were charged. the quantity with the measured quantities of the impurities (twice) - water: 1.0% (1.57%), methanol: 1.49% (1.6%), ethyl acetate: 0.1% (0.09%) ), hexane: (0.03%) - uncorrected] and 2.62 g (21.4 mmol) of 4- (dimethylamino) pyridine [water content (KF) = 0.09%] and the mixture Dissolve in 122 ml of anhydrous dimethylformamide (water content (KF) <0.01% by weight). added

Methylene chloride (256 mL) (water content (KF) <0.01% by weight) and the resulting homogeneous solution was cooled to -50 ° C. (During the addition of dichloromethane, the temperature of the reaction solution rises from 23 ° C to 25 ° C.) Triethylamine (ΝΕΰβ, water content (KF) = 0.08% w / w) (16 ml, 120 mmol) is added dropwise over three minutes. ] and the resulting solution was stirred at -50 ° C for 5 minutes and then triethylsilyl chloride (Et 3 SiCl) (18.6 mL, 111 mmol) was added dropwise. The addition of (Et ₃ SiCl) takes 10 minutes, during which time the reaction thermometer16 · · · · · 4 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · the temperature does not rise above -50 ° C and the solution is highly cloudy. The resulting mixture was stirred for 1 hour at about -50 ° C and then left (without stirring) in a freezer at -48 ° C for 22 hours. (In a parallel experiment, it was found that if the reaction mixture was stirred at -48 ° C for 8 hours, the conversion was about 60%.) The mixture was then removed from the freezer and heated to about -10 ° C. [TLC of the mixture, using ethyl acetate as solvent and phosphorus molybdic acid in ethanol as developer, shows no starting material present and gives the product a spot (Rf = 0.60)]. To the cold mixture was added 1 L ethyl acetate and washed with water (890 mL). The resulting aqueous layer was separated and extracted with ethyl acetate (250 mL). The combined organic layers were washed twice with 250 mL of 5.7% aqueous sodium dihydrogen phosphate (original pH 4.30 ± 0.05; the combined sodium dihydrogen phosphate washes (pH 5.57 ± 0.05), then washed with 250 ml of semi-saturated aqueous sodium chloride solution and then with 250 ml of saturated aqueous sodium chloride solution, dried over sodium sulfate and filtered and evaporate in a rotary evaporator. Each evaporation in a rotary evaporator was carried out in a 35 ° C water bath. The resulting semi-solid was dried under high vacuum (133 Pa; about 1 mm Hg) for a further 20 minutes to give 41.5 g of a white solid. The crude product is then dissolved in 400 mL of dichloromethane (heated in a 35 ° C water bath) and the volume of the resulting solution is reduced to about 150 mL in a rotary evaporator. Crystallization begins immediately and the mixture is allowed to stand at room temperature for 1 hour. Then 100 ml of hexane are added and * 9 · 9 · 9 · 9

9999 99 99

- 17 gently mix. The mixture was allowed to stand at 4 ° C for 16.5 hours, then filtered, rinsed three times with 250 mL of 1: 9 dichloromethane / hexane, and high vacuum (27 Pa; about 0.2 mm Hg). Dry for 42 hours to give 26.1 g (79%) of the title compound as a white powder. The mother liquor was evaporated in a rotary evaporator and the residue was recrystallized from dichloromethane to give 4.5 g (14%) of the title compound as a white crystalline solid. Recrystallization was carried out in the same manner as for the first batch: the solid was dissolved in methylene chloride (100 mL) without heating, and the resulting solution was reduced to about 7 mL in a rotary evaporator. Crystallization begins within 5 minutes, and the mixture is allowed to stand at room temperature for 1 hour and then at 4 ° C for 42 hours. The precipitated crystals were filtered off, washed through the filter with three 50 ml portions of methylene chloride / hexane (1: 9) and dried under high vacuum (27 Pa; about 0.2 mm Hg) for 18 hours. The 1H-NMR results of the two batches are identical. The total yield from the two doses is 93% (without correction).

M.p. 239-242 ° C (with decomposition), [α] ²² D = -53.6 ° (c = 1.0, chloroform)

TLC: Rf = 0.60 (silica gel, ethyl acetate) developing: phosphorus molybdic acid in ethanol.

The title compound can also be prepared in the following manner: One flame-dried and equipped with argon inlet,

Into a 250 mL 3-necked flask was placed 5.54 g (10 mmol) of 10-desacetylbaccatin III (water content 1.56 wt%, methanol 1.6 wt%), 0.49 g (4 mmol) 4 - (dimethylamino) pyridine and 24 ml ··· ·· <* · · ·· ♦ ♦ »« V · »* ^fc '- · · ····. ··, _t · »··

-isii N, N-dimethylformamide (dried on a pore size molecular sieve). The reaction mixture was stirred at room temperature until homogeneous. Then 50 ml of dichloromethane (HPLC grade, without purification) were added and the temperature was lowered to -50 ° C. Triethylamine (2.9 mL, 21 mmol) was added dropwise over 5 min, followed by triethylsilyl chloride (3.4 mL, 20 mmol) over 10 min. The reaction mixture was allowed to stand at -48 ° C for 21 hours, then diluted with 200 mL of ethyl acetate and 175 mL of water. (The reaction was monitored by TLC using ethyl acetate as eluant and ethanol phosphorous molybdic acid as eluent. The starting material had an Rf of 0.56 and the product had a concentration of 0.83.) The aqueous layer was separated and extracted with acetate. The organic layers were combined, washed twice with 50 ml of 5% aqueous potassium dihydrogen phosphate solution (pH 4.3), 50 ml of semi-saturated aqueous sodium chloride solution and then with 50 ml of sodium chloride solution. dried over sulfate and concentrated in vacuo to give the crude title compound as a solid (7.45 g). This was dissolved in hot CH 2 Cl 2 (75 mL) and the volume was reduced to 30 mL by hot evaporation to allow crystallization to occur, then allowed to stand at room temperature for 2 hours and then at 4 ° C for 16 hours. The precipitated crystals were filtered on a Buchner funnel, washed with 25 ml of a 10% cold solution in dichloromethane in hexane and dried in vacuo to give 5.38 g of the title compound. The mother liquor and washings were evaporated in vacuo and the solid residue was recrystallized by dissolving in 8 mL dichloromethane. This recrystallization gave a second crop of additional product (0.72 g). Thus, a total of 6.10 g (93%) of the title compound, 7-TES- (baccatin III), a white solid, m.p. 238-240 ° C, was obtained.

Melting point: 239-242 ° C.

[α] _D : -53.7 ° (c = 0; chloroform), [α] 22365. + 95.0 ° (c = 0, chloroform).

TLC: Rf = 0.53 (silica gel, 50% ethyl acetate / hexane), developed by UV and ethanol phosphorus molybdic acid;

Hl (homogeneity index) - 98.9%.

(ii) ([2aR- (2an, 4β, 4aE, 6β, 9α, 11β, 12q, 12an, 12ba) 1-6.12bis-bis-Acetoxy-12- (benzoyloxy) -2a, 3,4,4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-9,11-dihydroxy-4a, 8,13,13-tetramethyl-4 - [(triethylsilyl) oxyl-7,11- Preparation of methano-1H-cyclodeca- [3,4] benzo [1,2-b] oxet-5-one [7-O-TES- (baccatin III), Compound 4a2]

21.4 g (32.4 mmol) of 7-O-TES- (10-deacetylbaccatin III) prepared in step (i) above are combined with a 1 liter flame-dried mechanical argon stirrer and digital thermometer. In a 3-neck fitted flask, dissolve 350 ml of a mixture of sodium and benzophenone in freshly distilled tetrahydrofuran. The resulting solution was cooled to -70 ° C and 14.6 mL (37.3 mmol) of a 2.56 M solution of butyllithium in hexane (BuLi, tetrahydrofuran diphenylacetic acid solution at 0 ° C) was added dropwise over 23 minutes. tri-titrated solution). The reaction temperature does not rise above -68 ° C during the addition. After the addition of BuLi, a precipitate formed which was insoluble at -70 ° C. The resulting mixture was stirred at -70 ° C for 20 minutes and then warmed to -48 ° C to give a clear, homogeneous solution. After stirring at -48 ° C for 1/2 hour, acetic anhydride (4.6 ml, 49 mmol) distilled at 137-138 ° C under atmospheric pressure was added dropwise over 7 minutes. During the addition, the reaction temperature does not rise above -45 ° C. The resulting solution was stirred at -48 ° C for 20 minutes and then at 0 ° C for 1 hour. It is then diluted with 350 ml of ethyl acetate, washed with 250 ml of saturated ammonium chloride solution, and the layers are separated. The aqueous layer was dissolved in 200 mL of ethyl acetate. The combined organic layers were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and evaporated in a rotary evaporator. (Each evaporation in a rotary evaporator was carried out in a 35 ° C water bath.) The semisolid mixture yielded 24.2 g of a white solid under high vacuum (190 Pa; about 1.5 mmHg) in 1/2 hour. The crude product was dissolved in methylene chloride (300 mL) and the resulting solution was reduced to about 70 mL in a rotary evaporator. Crystallization begins within 1 minute. The mixture was allowed to stand at room temperature for 45 minutes and then at 4 ° C for 18 hours. The crystalline material is then filtered off, washed through a filter (3 x 100 mL, 1: 9 dichloromethane / hexane) and dried under high vacuum (27 Pa; about 0.2 mm Hg) for 19 hours to give 20.9 g 92.0%) of the title compound are obtained in the form of fine white needle crystals. The mother liquor was evaporated in a rotary evaporator and the residue was recrystallized from dichloromethane / hexane to give an additional 0.82 g of the title compound as tiny white needle crystals. Recrystallization was carried out as follows: the residue was dissolved in dichloromethane (10 ml) and the volume of the resulting solution reduced to about 5 ml in a rotary evaporator. After 1/2 hour at room temperature, crystallization does not begin. To the solution was added 5 mL of hexane in 1 mL portions and shaken gently. Then some crystals precipitate out. The mixture was allowed to stand at room temperature for 1/2 hour (further crystals precipitated) and stored in a refrigerator for 18 hours at 4 ° C. The crystals were filtered off, washed on the filter with dichloromethane / hexane (1: 9) and dried under high vacuum (19 Pa; about 0.15 mm Hg) for 21 hours.

The yield of the two doses taken together is 95.6%.

Melting point (with decomposition): 218-219 ° C.

[g] ²² D: -78.4 ° (c = 1.0, chloroform),

TLC Rf = 0.37 (silica gel; acetone and dichloromethane)

1: 9 mixture;

developer phosphorus molybdic acid in ethanol.

(b) {[2aR - (2aa, 4S, 4aSS, 65, 9a, 1 H, 12a, 12a [alpha], 12bac) -1-6,12b, -bis-acetoxy-12 - (benzoyloxy) -2a, 3,4, 4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-4 - [(triethylsilyl) oxy] -11-hydroxy-4a, 8,13,13-oxo-tetrametÍ1-5 7,11-Methano-1H-cyclodeca-3,41 benz- [1,2-bloxet-9-yl} - (2R *, 3S *) - 3- (benzoylamino) -3-phenyl-2 - ( 1-Methyl-1-methoxyethoxy) -propionate (Compound 5) 50.00 g (71.33 mol) of the compound prepared in step a) are dissolved in 125 ml of a mixture of sodium and benzophenone in freshly distilled tetrahydrofuran, and after complete dissolution, the solution is cooled to -50 ° C. With vigorous stirring, 55.1 ml (74.90 mmol) of a 1.36 M solution of lithium (hexamethyldisilazide) in tetrahydrofuran (LHMDS; titrated with 1,3-diphenylacetone-p-tosylhydrazone) is added dropwise over 20 minutes. ) so that the internal temperature does not rise above -48 ° C. After the addition was complete, the reaction mixture was warmed to -35 ° C and stirred at this temperature for 5 minutes.

To the reaction mixture was added dropwise a solution of 27.85 g (82.03 mol) of the compound of Example 3 (3) in 35 ml of tetrahydrofuran dropwise over 7 minutes. No significant increase in temperature was observed. The flask containing compound (3) was rinsed with 5 mL of tetrahydrofuran and the wash solution was poured into the reaction mixture. The temperature of the resulting solution was raised to 0 ° C by changing the dry ice bath to an ice-water bath and stirring the solution for a further 90 minutes. The reaction is monitored by reverse phase silica gel (RP-18 EM Sience WF25 ₄ g) _was carried out by TLC, 70:30 acetonitrile: water is used as eluent. The title compound has an Rf of 0.31, a 7-TES-taxol (i.e., a taxane derivative that contains a TES-O group at the 7-position instead of the hydroxy group), and a 7-TES- ( for baccatin III) 0.47 and for compound 3 0.63.

The reaction was quenched with 50 mL of pH 7 phosphate buffer followed immediately by 150 mL of saturated sodium bicarbonate solution. The reaction mixture was diluted with ethyl acetate (600 mL) and the layers were separated. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the title compound as a pale yellow solid (82.3 g). This was dissolved in 200 mL of hot ethyl acetate and 110 mL of hexane was added dropwise under reflux. The recrystallization mixture is set aside at room temperature for 2 hours (rapid precipitation begins on cooling) and allowed to stand in the refrigerator for 7 hours. The solid was filtered off and washed with cold ethyl acetate (5: 1, diluted with hexane (2 x 80 mL)). The resulting white crystalline material was dried on a suction filter for 1 hour and then at a pressure of about 79 mmHg overnight. 67.37 g of the title compound are obtained, 91% yield of pure 7-TES (baccatin III); ^X H NMR

0.4 mol ethyl acetate was present, yielding a corrected yield of 87%; the actual homogeneity index (HI) was 99.25% (95.73% for the title compound and 3.52% for 7-TES-taxol).

The mother liquor is concentrated to dryness by pouring in the washing solutions.

The residue was dissolved in hot ethyl acetate (25 mL) and hexane (40 mL) was added dropwise under reflux. After cooling to room temperature, the mixture is set aside at this temperature for 1 hour and then allowed to stand in the refrigerator for 7 hours. The solid is then filtered off and dried over a suction strainer and then at about 92 Pa (0.7 mm Hg) overnight. This afforded 6.06 g of the title compound having a homogeneity index (HI) of 96.6% (92.6% of the title compound and 4.0% of 7-TES-taxol).

M.p. 153-155 ° C, [α] 25 D -59.6 ° (c = 1, chloroform)

TLC: Rf = 0.31 (reversed phase HPTLC; acetonitrile / water 70:30; developed by UV).

Another method of preparing compound (5) involves coupling on 7-O-TES- (baccatin III) in situ, as follows:

7-O-TES- (baccatin III) (1.5177 mmol) was dissolved in dry tetrahydrofuran (3.5 mL) and cooled to -65 ° C. 0.5 L of lithium hexamethyldisilazide (LHMDS) is added dropwise and the reaction mixture is stirred for 20 minutes. Then 0.5 equivalents of acetic anhydride was added and stirring was continued for a further 20 minutes. The process for deprotection and acylation was repeated three times (using a total of 1.5 equivalents of LHMDS and 2.0 equivalents of acetic anhydride). During the formation of the anion a precipitate forms (the reaction mixture thickens). The mixture was heated to 0 ° C and allowed to stand at this temperature for 5 minutes.

It is then cooled to -50 ° C, treated with LHMDS dropwise and coupled directly with compound (3) (as in (b) above). Yield: 851 mg (55%) of 7-O-TES- (10-desacetyl baccatin III).

Example 2 {T2aR- (2aa ?, 45,4aE, 65, 9α ;, 10?, 12a ?, 12aa, 12bo?)] -6,12b, -bis-Acetoxy-12- (benzoyloxy) -2a , 3,4,4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-4 - [(triethylsilyl) oxy] -11-hydroxy-4a, 8,13,13-tetramethyl -5-oxo-7,11-methano-1H-cyclodeca-3,4-benz [1,2-b] oxet-9-yl} - (2R *, 3S *) - 3- (benzoylamino) - Preparation of 3-phenyl-2- (1-methyl-1-methoxyethoxy) propionate (2-MOP-7-triethylsilyl taxol, compound 5)

7-TES- (baccatin III) (5.00 g, 7.13 mmol) was dissolved in freshly distilled tetrahydrofuran (12.5 mL) from a mixture of sodium and benzophenone, and after complete dissolution, the solution was cooled to -50 ° C. With vigorous stirring, 7.85 mL (7.85 mmol) of a 1.00 M solution of LHMDS in tetrahydrofuran is added dropwise over a period of about 17 minutes, without increasing the internal temperature to above -48 ° C. Towards the end of the addition a precipitate forms which makes mixing more difficult. To continue vigorous stirring, additional tetrahydrofuran (1.5 mL) was added to the reaction mixture, which was heated to -35 ° C and stirred at this temperature for 10 minutes. The cloudy solution at -35 ° C was cooled back to -42 ° C and added dropwise to a solution of compound (3) (3.03 g, 8.92 mmol) in tetrahydrofuran (2.5 mL). The temperature is maintained between -19 and -10 ° C during the 7 minute addition. The flask and needle were rinsed with 0.5 mL of tetrahydrofuran. At the end of the addition, the resulting solution was heated to 0 ° C by changing the dry ice bath to an ice-water bath and stirring the solution for a further 75 minutes. The progress of the reaction was monitored by reverse phase silica gel TLC (EM Sience RP-18 WF254S). The title compound has an Rf of 0.31, a 7-TES taxol of 0.41 and a 7-TES (baccatin III) of 0.47.

The reaction was quenched by the addition of 12 mL of pH 7 phosphate buffer followed by 30 mL of saturated sodium bicarbonate solution. The reaction mixture was diluted with 100 mL of ethyl acetate and the layers were separated and the aqueous layer was washed with 10 mL of ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the title compound as a light brown solid (9.13 g). This was dissolved in 20 mL of hot ethyl acetate and 13 mL of hexane was added dropwise under reflux. The solution was allowed to stand at room temperature for 36 hours and then cooled for 2 hours. The solid was filtered off and washed twice with 10 ml of cold ethyl acetate diluted 5: 1 with hexane. (The material which was crystallized from the mother liquor and the washing solutions was filtered off and set aside. The former was 1.52 g, Hl 52.4, the latter 0.32 g, Hl 53.4). The resulting white crystalline material was dried on a kernel filter for 20 minutes and then at about 67 mmHg (0.5 mm Hg) overnight. 6.59 g of the title compound are obtained, 89% yield based on pure 7-TES- (baccatin III); actual H1 value was 99.3% (96.0% of the title compound and 3.3% of 7-TES-taxol).

M.p. 153-155 ° C, [α] 25 D -59.6 ° (c = 1, chloroform).

TLC: Rf = 0.31 (reversed phase HPTLC; acetonitrile / water 70:30; developed by UV).

Example 3 {[2aR- (2aa, 4β, 4aS, 6β, 9a, 11 ', 12a ¹ , 12aa, 12ba) 1-6.12b, -bis-Acetoxy-12- (benzoyl-oxy) -2a, 3 , 4,4a, 5,6,9,10,11,12,12a, 12b-dodecahydro-4,11-dihydroxy-4a, 8,13,13-tetramethyl-5-oxo-7,11-methano- Preparation of 1H-Cyclodexa-3,4,4-benzyl-1,2,2-bloxet-9-yl} - (2R *, 3S *) - 3- (benzoyl-amino) -3-phenyl-2-hydroxypropionate Γ

From the product of Example 5 above (Compound 5), 5.0 g (4.81 mmol, Hl 99.3%) of which 96.0% is compound (5) and 3.3% -TES-taxol], dissolved in 100 ml of ethanol and 80 ml of tetrahydrofuran, cooled to 0 ° C in an ice bath and added dropwise with 1.5 M hydrochloric acid, cooled to about -5 ° C, with vigorous stirring for 12 minutes. . The turbidity that appears during the addition of the hydrochloric acid solution is rapidly eliminated. The resulting clear solution was stirred at 0 ° C for 15 minutes and then allowed to stand at 4 ° C for 19.5 hours. At this time, an aliquot was obtained by HPLC (3 pm Phenyl BD column; 35% acetonitrile / 65% water linear gradient to 26 minutes; 100% acetonitrile linear gradient to 7 minutes; 35% acetonitrile / 65% water isocratic mixture to 7 minutes). , 6% taxol, 0.6% 7-TES taxol, and a total of 0.3% polar impurities and small amounts of other impurities. The reaction mixture was diluted with ethyl acetate (200 mL) and washed with cold (about 5 ° C) sodium bicarbonate (500 mL, then twice 200 mL). The wash is continued until the pH of the aqueous wash solutions reaches about 8.5.

The combined aqueous fractions were extracted with ethyl acetate (2 x 100 mL). The organic layers were combined, washed with brine (300 mL), dried (Na 2 SO 4), filtered and evaporated to give crude taxol (4.44 g, 97.7% as HPLC). It is dissolved in 25 ml of methanol diluted 1: 5.8 with isopropyl alcohol and diluted with 1.4 ml of water with gentle heating (heated to about 40 ° C in a 45 ° C water bath). The resulting solution was stored at room temperature under hexane for 16 hours. (The hexane atmosphere is created by placing the solution in which the crude taxol is dissolved in a mixture of methanol, isopropyl alcohol and water in another larger closed container containing 20 ml of hexane). The white solid (whose crystals are visible under a microscope) is filtered off, washed with 25 ml of cold (about 5 ° C) hexane and dried under high vacuum to give 3.8 g (93%) of a taxane as determined by HPLC. 99.0%. The mother liquor and the washings were evaporated under reduced pressure to give 0.28 g (7.0%) of a pale yellow crystalline material (HPLC value = 80.6%) which was set aside for further processing.

Melting point: 211-213 ° C, [α] D 25 -51.5 ° (c = 1, chloroform).

TLC: Rf = 0.22 (methanol: ethyl acetate: hexane 0.6: 4.0: 5.4, developed with UV and phosphorus molybdic acid).

Example 4

Preparation of Taxol

In a 2 liter polyethylene bottle containing 20 g (19.1 mmol) of compound 5 (2-MOP-7-triethylsilyl taxol) dissolved in a mixture of 800 ml of acetonitrile and 48 ml of pyridine at 0 ° C, 104 ml of aqueous hydrogen fluoride solution are added dropwise over 60 minutes. During addition, the internal temperature should not exceed 5 ° C. The clear solution was kept at 4 ° C for 24 hours without stirring. The reaction was monitored by HPLC (performed on a 3.9 x 150 mm column packed with Nova-Pak Phenyl (Waters) at a flow rate of 2 mL / min, the absorbance being measured at 227 nm). The chromatographic conditions are as follows: 0-26. min: (35% acetonitrile / 65% water) to 100% acetonitrile linear gradient, 26-28. min gradient from 100% acetonitrile (35% acetonitrile / 65% water), 28-35. 35 minutes acetonitrile / 65% water, isocratic.

Retention times:

7-TES-taxol: 13.73, taxol: 6.65,

10-deacetyl taxol: 4.96.

When the reaction time is 19 hours, the reaction mixture

0.36% of 7-TES taxol remains. After 24 hours, 7-TES-taxol and 10-deacetyl-taxol were no longer present in the reaction mixture (impurity index, II <0.04%). At this time, the solution was diluted with 1 L of ethyl acetate and washed twice with 800 mL of 1 M hydrochloric acid. The organic layers were combined, washed five times with 800 ml of saturated aqueous sodium bicarbonate solution and once with 300 ml of brine, dried over sodium sulfate, filtered and evaporated to give 17.46 (almost 100%) crude taxol as a white solid. in the form of a solid; The H1 value by HPLC was 80.6% and the yield was not corrected.

Melting point: 207.5-212 ° C (crystalline water) [α] D: -52.5 ° (c = 1, chloroform).

TLC: Rf = 0.22 (silica gel; methanol: ethyl acetate: hexane)

0.6: 4.0: 5.4; development: with UV and phosphorus molybdic acid).

Example 5

Preparation of Taxol

5.0 g (4.81 mmol) of 2-MOP-7- (triethylsilyl) -taxol 99.2% H1 (5) which is 95.7 Hl of 2-MOP-7-TES-. containing taxol] Dissolve in a mixture of ethanol (50 ml) and tetrahydrofuran (40 ml), cool to 0 ° C with an ice bath and add dropwise 50 ml of 1.5 M cooled to about -5 ° C over 40 minutes with vigorous stirring. aqueous hydrochloric acid solution. The turbidity that appears during the addition of the hydrochloric acid solution is rapidly eliminated. The resulting clear solution was stirred at -2 ° C for 1 hour and then allowed to stand at 4 ° C for 22 hours. Meanwhile, about 100-200 mg of taxol is precipitated as a white precipitate. After 20 hours of reaction, an aliquot of HPLC (3 μπι Phenyl BD column; 3 5% acetonitrile / 65% water linear gradient to 26 minutes; 100% acetonitrile linear gradient to 7 minutes; 35% acetonitrile / 65% water isocratic mixture). 7 minutes)

97.2% taxol, 0.2% 7-TES taxol and 0.7% 10-desacetyl taxol are present along with other minor impurities. The reaction mixture was diluted with ethyl acetate (200 mL) and washed with cold (about 5 ° C) sodium bicarbonate solution (400 mL, then 200 mL). The wash is continued until the pH of the aqueous wash solutions is about 8.5. The combined aqueous fractions were extracted with ethyl acetate (2 x 80 mL). The organic layers were combined, washed with 200 mL of brine, dried over sodium sulfate, filtered and evaporated

The crude taxol (4.2 g, 97.9%) is obtained as a white solid (4.2 g). It is dissolved in 31 ml of ethanol diluted 6: 4 with heptane and diluted with 0.15 ml of water with gentle heating (heated to about 30-35 ° C in a water bath). The resulting clear, homogeneous solution was stored at 4 ° C under hexane for about 20 hours. In this way, 0.18 g (4%) of a white solid (crystals visible under a microscope) is obtained in a second portion of the product having an H1 value of 92.0%.

Melting point: 207-208 ° C.

Optical rotation: [α] D = -52.3 ° (c = 1, chloroform)

TLC: Rf = 0.22 (silica gel; methanol: ethyl acetate: hexane 0.6: 4.0: 5.4, - development: UV and phosphorus molybdic acid),

HPLC: H1 = 98.6%.

• ·

- 32 PATENT CLAIMS

Claims (16)

PATENT CLAIMS A process for the preparation of a taxane derivative of the formula VII having a side chain ^R1 and ^R2 (i) both the same alkyl, or (ii) together form a cycloalkyl group, or (iii) together form a cycloalkenyl group, or (iv) together form a heterocyclic group; R ³ is alkyl; R ⁴ is aryl; r5 is hydrogen, arylcarbonyl or alkoxycarbonyl; and T is a taxane moiety directly bonded to the 13-position, and salts thereof, characterized in that a β-lactam of formula (I) or a salt thereof, wherein R ⁴ , R ² , R ³ , R ⁴ and R ³ are as defined above, in the presence of a coupling reagent, with a taxane derivative of the Formula VIII wherein T is as defined above, or a salt thereof; and optionally converting -OC (R ⁴ ) (R ² ) (R ³ ) of the compound of formula (VII) to a hydroxy group to form a side-chain taxane of formula (IX): • · ♦ ·· 33 R ⁴ , R ⁵ and T are as defined above - or a salt thereof. 2. The process of claim 1 wherein the taxane derivative of formula VIII is a compound of formula X wherein Bz is benzoyl; Ac is acetyl; R ⁷ is hydrogen, alkylcarbonyl, or a hydroxy protecting group; and r8 is hydrogen or a protecting group for a hydroxy group. 3. A process according to claim 2 wherein the taxane derivative of formula X is 7-O-trialkylsilyl (baccatin III). 4. The process of claim 1, wherein the coupling reagent is an alkali metal silyl amide base or a spherically inhibited alkali metal amide base. 5. The process of claim 4, wherein the coupling reagent is a heterocyclic group of a compound of formula XI wherein r9 and R10 are trialkylsilyl or cycloalkyl, or together with the nitrogen atom to which they are attached; and M is an alkali metal atom. • · · 4 9 · · »···» ·· ·· 6. The process of claim 5, wherein the coupling reagent is an alkali metal hexamethyldisilazide. 7. The process of claim 6 wherein the alkali metal hexamethyldisilazide is lithium hexamethyldisilazide. 8. The process of claim 2, wherein the resulting taxane moiety of the side-chain-bearing taxane derivative is deprotected. 9. The process of claim 8, wherein an acid is used to remove the protecting group (s). 10. A process according to claim 3 for the preparation of a taxane derivative of formula VII: wherein: ^R1 and ^R2 are the same and each is unsubstituted lower alkyl; R ² is unsubstituted lower alkyl; R ⁴ is phenyl; and r5 is benzoyl or tert-butoxycarbonyl. 11. The process according to claim 10, wherein the taxane derivative is taxol. 12. The process of claim 10, wherein the taxane derivative is a taxotere. 13. A side chain taxane derivative of the Formula VII: wherein: ^R1 and ^R2 (i) both the same alkyl, or (ii) together form a cycloalkyl group, or (iii) together form a cycloalkenyl group, or (iv) together form a heterocyclic group; R 3 is alkyl; R ⁴ is aryl; r5 is hydrogen, arylcarbonyl or alkoxycarbonyl; and T is a taxane moiety directly attached to the 13-position and their salts. 14. A compound of formula (VII) as claimed in claim 13 wherein R ¹ and R ² are the same two unsubstituted lower alkyl groups; r3 is unsubstituted lower alkyl; R ⁴ is phenyl; and r5 is benzoyl or tert-butoxycarbonyl. 15. 2- (1-Methyl-1-methoxy-ethoxy) -7- (triethylsilyl) -taxol according to claim 13. 16. A process for the preparation of a taxane derivative having a side chain at C-13, characterized in that a taxane having a hydroxy group at C-13 is present in the presence of an alkali metal silyl amide base or a sterically hindered alkali metal amide base. with a β-lactam capable of forming a side chain.