SI9300183A - water soluble camptothecin derivates - Google Patents

Abstract

The present invention relates to water-soluble camptothecin derivatives of formula (I) Sl 9300183 A lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or iii) R1 and R2 taken together with the binding nitrogen forms a saturated heterocyclic group with 3 to 7 formula atoms (IA) where: n represents an integer 1 or 2; and i) R1 and R2 independently represent hydrogen, lower alkyl, (C3-7) cycloalkyl, (C3-7) -cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl; ii) R1 represents hydrogen, lower alkyl, (C3-7) cycloalkyl, (C3-7) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl and R2 represents -COR3 where: R3 represents hydrogen, lower alkyl, perhalo-lower alkyl, (C3-7) cycloalkyl, (C3-7) cycloalkyl where: Y represents O, S, CH2 or NR4 where: R4 represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted by one or more lower alkyl groups, halogen, nitro, amino, lower alkyl amino, feather lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or -COR5, wherein: R5 represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, lower-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups; and pharmaceutically acceptable salts thereof; their use in the treatment of tumors and procedures for their preparation.

Description

(57) The present invention relates to water-soluble camptothecin derivatives of formula (I)

Sl 9300183 A

lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or iii) R ¹ and R ² taken together with the binding nitrogen form a saturated heterocyclic group of 3 to 7 atoms of formula (IA)

where: n represents an integer 1 or 2; and i) R ¹ and R ² independently represent hydrogen, lower alkyl, (C 3-7) cycloalkyl, (C 3-7) -cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl; ii) R ¹ represents hydrogen, lower alkyl, (C3-7) cycloalkyl, (C3-7) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl, and R ² represents -COR ³ where R ³ represents is hydrogen, lower alkyl, perhalo-lower alkyl, (C3-7) cycloalkyl, (C3-7) cycloalkyl, wherein Y represents O, S, CH 2 or NR ⁴ wherein R ⁴ represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted with one or more groups lower alkyl, halogen, nitro, amino, lower alkyl amino, perhalo lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or -COR ⁵ , wherein: R ⁵ represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, perhalo-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups; and pharmaceutically acceptable salts thereof; their use in the treatment of tumors and the procedures for their preparation.

JL

Glaxo Inc

Water soluble camptothecin derivatives

The present invention relates to water-soluble camptothecin derivatives substituted at position 7, to their use in the treatment of tumors and to methods for their preparation.

BACKGROUND OF THE INVENTION

Camptothecin, a natural cytotoxic alkaloid, is a topoisomerase I inhibitor and an effective antitumor agent. It was first isolated from the leaves and bark of the Chinese plant Camptotheca accuminata, Wall, et al. (J. Am. Chem. Soc. 88 3888 (1966)).

As described, camptothecin is a fused ring system consisting of quinoline (A and B) attached to the pyrrolidine ring (C), attached to the α-pyridone ring (D), which in turn is attached to the lactone ring (E).

It has an asymmetric carbon at position 20 which forms two possible enantiomeric forms. However, the compound found in nature is in the S configuration as shown above.

Cytotoxic agents are often used to control or suppress tumors, i.e. are chemotherapeutic agents. Camptothecin cytotoxic activity is thought to be directly related to camptothecin efficiency as a topoisomerase inhibitor. [For a more detailed explanation of the function of topoisomerase, see A. Lehninger, Principles of Biochemistry, 813, Worth Publishers, New York (1982); LF Liu DNA Topoisomerases, CRC Critical Review in Biochemistry, 1-24, 15 (1983) and H Vosberg, DNA Topoisomerases: Enzymes that Control DNA Conformation, Current Topics in Microbiology and Immunology, 19, Springer-Verlag, Berlin (1985)] . In particular, camptothecin has been shown to be effective in treating leukemia (L1210) and certain solid tumors in laboratory animals, e.g. see Chem. Rev. 23, 385 (1973) and Cancer Treat. Rep. 60,1007 (1967).

Unfortunately, the clinical outlook for camptothecin is an effective antitumor agent has not been fully met. Camptothecin is essentially insoluble in physiologically compatible aqueous media and needs to be modified to make it soluble enough for parenteral administration, the preferred form of antitumor therapy. The soluble can be made by forming its sodium salt, i.e. by opening lactone with sodium hydroxide (see F. M. Muggia, et al., Cancer Chemotherapy Reports, pt. 1.56, No. 4,515 (1972)). Vendas M.C. Wani, et al., J. Med. Chem. 23, 554 (1980), described the α-hydroxy lactone portion of ring E as an absolute requirement for antitumor activity.

There are examples of modifications and derivatives of camptothecin prepared to improve its water solubility. Although many derivatives were active in vitro and in early animal studies using leukemia (L-1210) models, they were non-rejuvenating in chronic animal models that included implanted solid tumors.

Miyasaka, et al., U.S. Pat. Patent no. No. 4,399,282 describes a group of camptothecin derivatives substituted at position 7 with, inter alia, hydroxymethyl and alkoxymethyl. Furthermore, Miyasaka, et al. in the U.S. patent no. No. 4,399,276 describes camptothecin 7-aldehyde and certain related aldehyde derivatives such as acetals, oximes and hydrazones. Recently, Vishnuvajjala, et al., In U.S. Pat. patent no. No. 4,943,579 required protection for a range of water-soluble camptothecin derivatives with substituents on the A ring, as well as Boehm, et al., In European Patent Application 0 321 122 A2. Other examples of camptothecin derivatives include Miyasaka, et al., U.S. Pat. patent no. No. 4,473,692 and nos. 4,545,880; and W. Kingsbury et al., J Med. Chem., 34, 98 (1991). None of these references describes compounds with an antitumor activity greater than that of camptothecin alone.

Wani and colleagues have described that 10,11-methylenedioxycamptothecin is more effective than unsubstituted camptothecin (see M. C. Wani, et al., J. Med. Chem. 29, 2358 (1986) and 30, 2317 (1987)). However, its water solubility is just as poor as that of camptothecin, which severely limits its clinical utility.

We have now discovered water-soluble analogs of camptothecin with good topoisomerase I inhibitory activity in vitro and pronounced antitumor activity in vivo.

Summary of the Invention

One aspect of the present invention is water-soluble camptothecin analogues of formula (I)

where n represents an integer 1 or 2; and

i) R ¹ and R ² independently represent hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl;

ii) R ¹ represents hydrogen, lower alkyl, (C ₃ ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl, and

R ² represents-COR ³ , '4 where:

R ³ iii) represents hydrogen, lower alkyl, perhalo-lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or

R ¹ and R ² taken together with the binding nitrogen form a saturated heterocyclic group of 3 to 7 atoms of formula (IA)

where:

Y represents O, S, CH ₂ or NR ⁴ where:

R ⁴ represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted with one or more groups lower alkyl, halogen, nitro, amino, lower alkyl amino, perhalo lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl;

or

-COR ⁵ , where:

R ⁵ represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, perhalo-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups;

and pharmaceutically acceptable salts thereof.

Pharmaceutically acceptable salts include, but are not limited to, salts with inorganic acids such as hydrochloride, sulfate, phosphate, diphosphate, hydrobromide and nitrate, or salts with organic acid such as acetate, malate, maleate, fumarate, tartrate, succinate, citrate, lactate, methanesulfonate , p-toluenesulfonate, palmoate, salicylate and stearate. Other acids such as oxalic, although not pharmaceutically acceptable alone, may be useful as intermediates in the preparation of the compounds of the present invention and their pharmaceutically acceptable salts.

The lactone ring, ring E, can be opened with alkali metal or alkaline earth metal bases, e.g. sodium hydroxide or calcium hydroxide to form alkali metal or alkaline earth metal salts of the corresponding open E ring form of the compounds of formula (I). Due to its better solubility in water, the E ring form can be advantageously purified by conventional recrystallization techniques. Thus, said opening E ring form can be used as an intermediate for the formation of compounds of formula (I), e.g. by treatment with an acid, e.g. hydrochloric acid to obtain the purified form of the compounds of formula (I).

As mentioned above, the camptothecin moiety has an asymmetric carbon atom at position 20, which forms two possible enantiomeric forms, i.e. R and S configuration. The present invention includes both enantiomeric forms and all combinations of these forms. For clarity, where no specific configurations at position 20 in the structural formulas are described, it is understood that both enantiomeric forms and mixtures thereof are represented. Unless otherwise stated, the nomenclature convention (R, S) is a racemic (approximately equal fraction) mixture of R and S enantiomers, while (R) and (S) are essentially optically pure R or. With the enantiomers. The present invention also encompasses other forms of the compound of formula (I), such as solvates, hydrates, polymorphs, and the like.

Another aspect of the present invention is a method for inhibiting topoisomerase type I in mammalian cells, comprising administering to the patient a topoisomerase inhibitory amount of a compound of formula (I) and a method for treating a tumor in a mammal comprising administering to the mammal having a tumor effective antitumor amounts of a compound having formula (I). A further aspect includes pharmaceutical preparations containing a compound of formula (I) as the active ingredient. Within the scope of the present invention there are also processes for the preparation of compounds of formula (I) and related novel chemical intermediates for use in the synthesis as intended herein. A further aspect includes pharmaceutical preparations containing a compound of formula (I) as the active ingredient. Processes for the preparation of compounds of formula (I) and related novel chemical intermediates used in the synthesis as intended herein are also within the scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Compounds

As used herein, the term lower with respect to alkyl and alkoxy means 1-6 carbons and with respect to alkenyl means 3-6 carbons (provided that the double bond is not bound to carbon bound to nitrogen). The term perhalo means all hydrogen substituted by halogen, e.g. lower alkyl alkyl, e.g. trifluoromethyl. The term aryl means phenyl or naphthyl.

The individual compounds of formula (I) are those wherein:

R ¹ and R ² represent:

i) independently; hydrogen, (C ₁₄ ) alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl (C ₁₄ ) alkyl, (C ₃₄ ) alkenyl, hydroxy (C ₁₄ ) alkyl, (C ₁₄ ) alkoxy (C ₁₄ ) alkyl , or ii) taken together with nitrogen, form aziridine, azetidine, pyrrolidine, piperidine, hexamethylenimine, imidazolidine, pyrazolidine, isoxazolidine, piperazine, N-methylpiperazine, homopiperazine, N-methylhomopiperazine, thiazolidine, isothiazolidin, or isothiazolidine

One preferred group of compounds of the present invention are compounds of formula (I) wherein:

n represents an integer 1 or 2; and

i) R ¹ and R ² independently represent hydrogen, lower alkyl (e.g. methyl, ethyl) or hydroxy lower alkyl (e.g. hydroxyethyl);

ii) R ¹ represents hydrogen and R ² represents -COR ³ , where R ³ represents perhalo-lower alkyl (e.g. trifluoromethyl); or iii) R ¹ and R ² taken together with the binding nitrogen tovrita azetidine, pyrrolidine, piperidine, morphoin, thiomorpholine or piperazine, optionally N-substituted with lower alkyl (e.g. methyl); phenyl; phenyl substituted with one or more perhalo-lower alkyl (e.g. trifluoromethyl) or lower alkoxy (e.g. methoxy) groups; or -COR ⁵ , wherein R ⁵ represents lower alkoxy (e.g. butoxy); and pharmaceutically acceptable salts thereof.

The specific compounds of formula (I) are:

Example Number The name of a compound

1. 7-dimethylaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin,

2. 7-dimethylaminomethylene-10,11-methylenedioxy-20 (S) -camptothecin,

3. 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

4. 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

5. 7-morpholinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

6. 7-morpholinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

7. 7-Pyrrolidinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

8. 7-piperidinomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin,

9. 7-piperidinomethylene-10,1 l-ethylenedioxy-20 (R, S) -camptothecin,

10. 7- (4-methylpiperazinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

11. 7- (4-methylpiperazinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

12. 7-diethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

13. 7-diethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

14. 7-diethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

15. 7-N-methylethanolaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin,

16. 7-N-methylethanolaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

17. 7-diethanolaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin,

18. 7-Diethanolaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

19. 7-azetidinomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin,

20. 7-azetidinomethylene-10,11-methylenedioxy-20 (S) -camptothecin,

21. 7-thiomorpholinomethylene-10,1 l-ethylenedioxy-20 (S) -camptothecin,

22. 7-azetidinomethylene-10,1 l-ethylenedioxy-20 (S) -camptothecin,

23. 7-4-methylpiperazinomethylene-10,1 l-methylenedioxy-20 (S) -camptothecin,

24. 7-Trifluoroacetamidomethylene-10,11-ethylenedioxy-20 (S) -camptothecin,

25. 7-Trifluoroacetamidomethylene-10,11-methylenedioxy-20 (S) -camptothecin,

26. 7-Aminomethylene-10,1 l-ethylenedioxy-20 (S) -camptothecin dihydrochloride,

27. 7-Aminomethylene-10,1 l-methylenedioxy-20 (S) -camptothecin dihydrochloride,

28. 7-tert-Butyloxycarbonyl-piperazinomethylene-10,11-ethylenedioxy-20 (S) camptothecin,

29. 7-piperazinomethylene-10, 11-ethylenedioxy- (S) -camptothecin and trifluoroacetic acid salt,

30. 7- (a, a, α-Trifluoro-m-tolyl) -piperazinornethylene-10,1 l-ethylenedioxy-20 (S) camptothecin,

31. 7- (2-Methoxyphenyl-piperazino) methylene-10,11-ethylenedioxy-20 (S) -camptothecin, and

32. 7-Phenylpiperazinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin.

The other individual compounds of formula (I) are those of formula (Γ)

where n represents an integer 1 or 2;

R ^1a and R ²³ represent:

i) independently hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl, or ii) together with a bonding nitrogen, form a heterocyclic group of 3 to 7 atoms of formula (IA ')

(IA ') where

Y ^a represents O, S, O 2 NH or N (lower alkyl), and the pharmaceutically acceptable salts thereof.

Preparation of compounds

According to one general procedure (A), compounds of formula I can be prepared by the procedure shown in step 2 of scheme I below:

SCHEME I

In Step 1 of Scheme I, a compound of Formula (II) wherein X is a leaving group (as defined in J. March, Advanced Organic Chemistry, 3rd ed., P. 179, John Wiley & Sons, New York (1985) ), e.g. halogen, e.g. chloro, can be reacted with a compound of formula (III) by the process described in U.S. Patent 4,894,456 (hereinafter, '456), issued January 16, 1990, by Wall et al., incorporated herein by reference to obtain a compound with formula (IV).

In step 2 (general process A), the compounds of formula (IV) can be converted to compounds of formula (I) by displacement of the leaving group, X, with a compound of formula (V), wherein R ¹ and R ² are as defined for formula (I). This displacement reaction can be conveniently carried out in a solvent system, e.g. water, (C _M ) alkanol, (C _M ) alkylenediol, 1-hydroxy-2methoxyethane, dimethylacetamide (DMAC), N-methylpyrrolidinone, dimethylformamide (DMF), tetrahydrofuran (THF), dimethylsulfoxide (DMSO), toluene or a combination of these solvents the presence of an excess amine, i.e. an excess of a compound of formula (V), with or without a base, e.g. of potassium carbonate.

This process is particularly useful for the preparation of compounds of formula (I) wherein none of R ¹ and R ² is hydrogen.

According to another general procedure (B), the compounds of formula (I) can be prepared by the procedure shown in step 2a of Scheme IA below:

SCHEME IA

In step 1a, the compound of formula (V) is reacted with the compound of formula (II) to give the compound of formula (IIA), wherein R ¹ and R ^{2 are} as defined for compounds of formula (I). This reaction can be carried out under conditions similar to those described in General Procedure (A) (Scheme 1, Step 2).

In Step 2a (General Procedure B), the compound of Formula (IIA) is reacted with the compound of Formula (III) in a similar manner as described above in Scheme 1, Step 1 to give the compound of Formula (I).

In a particular embodiment of process (B), the compounds of formula (I) can be prepared by the procedure shown in Scheme IB below:

X

Scheme 1B

In step lb, a compound of formula (Va) (wherein Hal is halogen, i.e., fluoro, chloro, bromo or iodo) e.g. trifluoroacetamide, is reacted with a compound of formula (II) in a polar, aprotic solvent, e.g. acetonitrile, in the presence of a base soluble in a polar aprotic solvent e.g. cesium carbonate if the solvent is acetonitrile to give the compound of formula (Ilb).

In step 2b, the compound of formula (Ilb) is reacted with the compound of formula (III) in a similar manner to that described in Scheme 1, step 1 to obtain the compound of formula (IVb).

In step 3b, the compound of formula (IVb) is treated with an acid, H ⁺ B ', such as a mineral acid, e.g. hydrochloric acid to give a compound of formula (Ib), i.e. a salt of a compound of formula (I). The compound of formula (Ib) can be treated with a base, using a standard technical procedure, to obtain a corresponding free base. The free base can then, if desired, be converted by conventional means into a pharmaceutically acceptable salt.

This alternative process is particularly useful for the preparation of compounds of formula (I) wherein both R ¹ and R ^{2 are} hydrogen or R ^{2 is} hydrogen.

The compounds of formula (II) can be prepared according to the procedure shown in Scheme II:

SCHEMAII

In step 1 of Scheme II, the compound of formula (VI) is reacted with an acylating agent, e.g. alkanoic acid halide (C _{2 5} ) or alkanoic acid anhydride (C _{2 5} ), e.g. acetyl chloride or acet anhydride, in the presence of a weak base, e.g. of potassium carbonate, in a polar, aprotic solvent, e.g. chloroform to give the compound of formula (VII) wherein Ac (C _{2 5} ) is an acyl group.

In step 2, the compound of formula (VII) is reacted with a compound of formula (VIII), wherein X is a leaving group as defined for the compounds of formula (IV) and Hal is halogen, in the presence of a metal halide, e.g. of zinc chloride, in a polar, aprotic solvent, e.g. nitromethane to give the compound of formula (IX). The compound of formula (VIII) may be e.g. haloacetyl halide, e.g. chloroacetyl chloride or haloacetonitrile, e.g. chloroacetonitrile.

In step 3, the compound of formula (II) is formed by removing the acyl group, Ac, from the compound of formula (IX), i.e. deacylation, using methods known in the art, such as those described in T. Green, Protective Groups and Organic Chemistry, Chapter 7, John Wiley, New York (1981). E.g. the compound of formula (IX) can be heated at reflux in concentrated hydrochloric acid and the resulting salt neutralized with a base, e.g. sodium hydroxide to give the compound of formula (II).

In step 2a of Scheme II, when the compound of formula (VI) is an ethylenedioxy compound, i.e. n is 2, it can be directly reacted with a compound of formula (VIII) without first protecting the amino group by acylation to give the corresponding compound of formula (II).

Alternatively, the compounds of formula (II) can be prepared according to the procedure described by T. Sugasavva, et al., J. Org. Chem., 44,578 (1979).

The compound of formula (III) can be prepared according to the procedure described by Wall, et al., '456, in column 11, starting in row 30. From Scheme 1 it is apparent that the configuration of the asymmetric carbon in the compound of formula (III) will affect the configuration of the compounds of formula (I). The racemic compound of formula (III) can be converted to any of its enantiomers by the procedure described by Wani, et al., In U.S. Pat. US Patent 5,053,512 (hereinafter '512'), which is incorporated herein by reference.

New intermediate compounds of formulas (II), (IIA) and (IV) are within the scope of the present invention.

According to another general process (D), a compound of formula (I) of the present invention can be converted to another compound of the present invention using conventional methods.

Thus, e.g. a compound of formula (I) wherein one or more of R ¹ and R ² represent a hydrogen atom is alkylated using conventional techniques. The reaction can be carried out using a suitable alkylating agent such as alkylhalide, alkylthylsylate or dialkyl sulfate. The alkylation reaction can be conveniently carried out in an organic solvent such as an amide, e.g. dimethylformamide or ether, e.g. tetrahydrofuran, preferably in the presence of a base. Relevant bases include e.g. alkali metal hydrides such as sodium hydride, alkali metal carbonates such as sodium carbonate, or alkali metal alkoxides such as sodium or potassium methoxide, ethoxide or t-butoxide. The alkylation reaction is suitably carried out at a temperature of 25 to 100 ° C.

Alternatively, a compound of formula (I) wherein one or more R ¹ and R ² represent a hydrogen atom can be converted to another compound of formula (I) by reductive alkylation. Reductive alkylation with a suitable aldehyde or ketone can be carried out using an alkaline earth metal borohydride or cyanoborohydride. The reaction may be carried out in an aqueous or non-aqueous reaction medium, suitably in alcohol, e.g. methanol or ethanol or ether, e.g. dioxane or tetrahydrofuran, optionally in the presence of water. The reaction may conveniently be carried out at a temperature in the range of from 0 to 100 ° C, preferably from 5 to 50 ° C.

Alternatively, a compound of formula (I) wherein one or more R ¹ and R ² represent a lower alkenyl group may be converted to another compound of formula (I) wherein R ¹ or R ² represents a lower alkyl group. The reduction can be conveniently carried out in the presence of hydrogen and a metal catalyst, e.g. Raney nickel or a catalyst of precious metal such as palladium, platinum, platinum oxide or rhodium which can be applied, e.g. on charcoal. The reaction may be carried out in a solvent such as an alcohol, e.g. ethanol and suitable at a temperature of -10 to + 50 ° C, preferably 20 to 30 ° C.

Alternatively, compounds of formula (I) wherein R ² represents a hydroxyalkyl group may be prepared by reduction of a compound of formula (I) wherein R ² represents a COR ³ group, wherein R ³ represents a lower alkoxy group. The reduction can be conveniently carried out using a suitable hydride reducing agent, e.g. lithium aluminum hydride or lithium triethylborohydride, in a suitable solvent such as ether, e.g. diethyl ether, tetrahydrofuran or dioxane, or a hydrocarbon such as toluene. The reaction is suitably run

Ιό at -78 to 100 ° C, preferably at about 0 ° C.

According to another general procedure (E), a compound of formula (I) of the present invention or a salt thereof can be prepared by exposing a protected derivative of formula (I) or a salt thereof to be metabolized to remove a protecting group or groups.

Thus, in the previous step of preparing a compound of formula (I) or a salt thereof, it was necessary and / or desirable to protect one or more sensitive groups in the molecule in order to prevent adverse side reactions.

The protecting groups used in the preparation of the compounds of formula (I) can be used in the conventional manner. See, e.g. Protective Groups in Organic Chemistry 'by Ed.J.F.W.McOmie (Plenum Press 1973) or Theodora W Greene's Protective Groups in Organic Synthesis (John Wiley and Sons 1981).

Conventional amino protecting groups may include e.g. aralkyl groups such as benzyl, diphenylmethyl or triphenylmethyl groups; and acyl groups such as N-benzyloxycarbonyl or t-butoxycarbonyl. Thus, compounds of general formula (I) wherein one or more groups R ¹ and R ² represent hydrogen can be prepared by deprotecting the corresponding protected compound.

Hydroxy groups can be protected, e.g. with aralkyl groups such as benzyl, diphenylmethyl or triphenylmethyl groups, acyl groups such as acetyl, silicon protecting groups such as trimethylsilyl or t-butyl dimethylsilyl groups, or such as tetrahydropyran derivatives.

Removal of any protecting groups present can be achieved by conventional procedures. Thus, an aralkyl group such as benzyl can be cleaved by hydrogenolysis in the presence of a catalyst (e.g., palladium on carbon); an acyl group such as N-benzyloxycarbonyl can be removed by hydrolysis with e.g. of hydrogen bromide in acetic acid or by reduction, e.g. by catalytic hydrogenation; silicon protecting groups can be removed, e.g. by treatment with fluoride ion or by hydrolysis under acidic conditions; tetrahydropyran groups can be cleaved by hydrolysis under acidic conditions.

It should be appreciated that in any of the general procedures (A) to (D) described above, it may be necessary or desirable to protect any of the sensitive groups in the molecule as just described. So a metabolic step can include

ΓΤ Removal of the protection of a protected derivative of the general formula (I) or a salt thereof is carried out by any of the procedures (A) to (D) described above.

Thus, in a further aspect of the present invention, the following reactions, if necessary and / or desired, can be carried out in any suitable sequence according to any of the processes (A) to (D) (i) removing any protecting groups; and (ii) converting compound (I) or a salt thereof into a pharmaceutically acceptable salt thereof.

Where we want to isolate a compound of the present invention as a salt, e.g. as an acid addition salt, this can be achieved by treating the free base of general formula (I) with a suitable acid, preferably an equivalent amount, or with creatinine sulfate in a suitable solvent (e.g., aqueous ethanol).

As well as being used as the last major step in the preparatory sequence, the general procedures outlined above for the preparation of the compounds of the present invention can also be used to introduce the desired groups in the intermediate step of preparing the desired compound. In such multi-step processes, therefore, it must be borne in mind that the reaction sequence must be chosen so that the reaction conditions do not affect the groups present in the molecule desired in the final product.

The biological activity of the compounds of formula (I) appears to be in the S enantiomer and the R enantiomer has little or no activity. Thus, the S enantiomer of a compound of formula (I) is generally more preferred than the mixture of R and S, such as the racemic mixture. However, if the R enantiomer is desired, e.g. for control studies or syntheses of other compounds, it may be suitably prepared by the above procedure using the R enantiomer of a compound of formula (III) prepared according to instructions' 512.

The compound of formula (I) prepared according to reaction scheme I, IA or IB can be purified by conventional procedures, e.g. chromatography, distillation or crystallization.

IS

In vitro analysis of the vaccine complex

The data in Table A below show the relative topoisomerase type I inhibitory activity of compounds of formula (I). This analysis, performed according to the procedure described in Hsiang, Y. et al., J. Biol. Chem., 260: 14873-14878 (1985) is in good agreement with the in vivo antitumor activity of topoisomerase inhibitors in animal models of cancer, e.g. camptothecin and its analogs. See Hsiang et al., Cancer Research, 49: 43854389 (1989) and Jaxel et al., Cancer Research, 49: 1465-1469 (1989).

Those compounds expressing marked activity at concentrations greater than 2000 nM (+ in Table A) are considered weak to moderately active, while those with activity at concentrations less than 500 nM (+ + ++ in Table A) are considered highly active . IC ₅₀ means the concentration of a compound of formula (I) in which 50% of the substrate DNA is occupied by topoisomerase I.

TABELAA

Topoisomerase inhibitory activity of compounds of formula (I) in fission complex analysis

Relative IC *

Example no. Isomeric form

2 (S) + + + + 6 (S) + + + + 11 (S) + + + + 1 (R, S) + + + + 17 (R, S) + + + + 5 (R, S) + + + + 4 (S) + + + 9 (R, S) + + + 10 (R, S) + + + 13 (R, S) + + + 16 (R, S) + + 7 (R, S) + + 15 (R, s) + + 16 (R, S) + + 19 (R, S) + + 8 (R, S) +

* IC ₅₀ range

Symbol nM + + + + <—500 + + + <—1000> —500 + + <-2000> -1000 + > -2000

The compounds of formula (IV) have also been found to have good topoisomerase I and a hybrid activity.

Human tumor grafts

Over the years, human grafts heterotransplanted into a nude mouse have been widely used to analyze the anti-tumor effects of cancer chemotherapeutic agents. See Giovanella, B.C., Stehlin, Jr., J.S. Shepard, R.C. and Williams, Jr., L.J., Correlation between response to chemotherapy of human tumors in patients and nude mice, Cancer 52: 1146-1152, (1983); Boven, E. & Winograd, B, Eds. The Nude Mouse in Oncology Research CRC Press, Inc., Boca Raton, FL, (1991); in Fiebig, H.H., Comparison of tumor response in nude mice and in patients, Human Tumour Xenografts in Anticancer Drug Development, Winograd, B., Peckham, M.J. and Pinedo, H.M., Eds., E.S.O. Mongraphs, Springer, Heidelberg, 25 (1988).

In general, human tumor grafts retain not only the histological, biochemical and antigenic characteristics but also the chemo-sensitivity of the original tumor tissue (Boven, et al., Supra). Long-term studies have provided evidence that human tumor grafts retain important biological properties of the original tumor, including biological instability, as it is known to occur in patients' tumors (Boven, et al., Supra). Most importantly, few researchers have reported good correlations between the effects of drugs in human tumor grafts and clinical outcomes in human patients (Giovanella, et al., And Fiebig supra).

In vivo analysis of human colorectal adenocarcinoma HT-29 graft

For this modified version of the assay described by BC Giovanella, et al., Science, 246 1046 (1989), female NU / NU mice weighing 21 ± 2 g were used. Control and test animals were injected subcutaneously in the sub-scapular area with a suspension of 10 ⁶ viable human colon colon HT-29 tumor cells at day 0. The tumors were allowed to grow for 2 weeks before drug administration. Multiple doses are selected for each drug based on its in vitro activity against topoisomerase I. Each dosage level group contains 8 animals. The test compounds are prepared either in 0.1 M acetate buffer, pH 5 (carrier a) or in 87.5% phosphate-filled brine, 12.375% dimethylsulfoxide and 0.125% Tween 80 (ICI America brand for polyoxyethylene sorbitan monooleate) (carrier b ) and given subcutaneously twice weekly for 5 weeks, starting on day 14. Doses are given on a mg / kg basis based on the mean body weight for each cage.

Tumor weight is calculated from two measurements of a rectangular sheath tumor, using the formula, tumor weight = length x width ² -? 2 in mm. For each animal, the tumor weight was observed over the course of the experiment. For each group, the results are expressed as the ratio of the median tumor mass immediately after 5 weeks of treatment (day 50) divided by the median tumor mass immediately before treatment (day 14). The results are expressed in Table B. For each of the vehicle controls, the ratio is approximately 20, indicating that the tumor, in the absence of drug treatment, increased in weight approximately 20-fold over the course of the experiment. In contrast, a ratio of 1 indicates that the tumor is stagnant, while a ratio of less than 1 indicates a tumor regression. Thus, compounds 4 and 6 cause tumor retention, while compounds 11 and 23 cause tumor regression. The criterion for antitumor activity is at least 50% inhibition of tumor growth after 5 weeks of dosing (day 50) giving a ratio less than or equal to 10.

TABLE B

Optimal dose of in vivo antitumor activity

Compound (mg / kg) (tumor weight ₅₀ / tumor weight control - 20.0 ^a , 21.8 ^b (carrier itself) 2 0.8 l, 8 ^b 4 7.0 l, 3 ^a - l, 0 ^b 6 1.0 l, 0 ^b 11 9.0 0.6 ^a 14 2.0 2.0 ^a 20 1.5 l, 5 ^a 22 12,0 l, 6 ^a 23 3.0 0.5 ^a

a.

b.

carrier 0.1 M acetate buffer, pH 5 carrier 87.5% phosphate-filled saline, 12.375% dimethylsulfoxide and 0.125% Tween 80.

'22

Usefulness

According to such action, the compounds of formula (I) are active against a wide variety of mammalian tumors (including human) and cancerous growths, such as cancers of the mouth and pharynx (lip, tongue, mouth, pharynx), esophagus, stomach, small intestine , colon, rectum, liver and bile passages, pancreas, larynx, lung (including non-small cell lung carcinoma), bone, connective tissue, skin, rectum, breast, cervix, corpus indometrium, ovary, prostate, testes, bladder, kidney and other urinary tissues, eye, brain and central nervous system, thyroid and other endocrine glands, leukemia, (lymphocytic, granulocytic, monocytic), Hodgkin's disease, non-Hodgkin's lymphomas, multiple myeloma, etc. Here, the terms tumor cancer and cancerous growth are used synonymously.

The amount of the compound of formula (I) required to be effective as an antitumor agent will, of course, vary with the individual mammal being treated and ultimately dependent on the judgment of the physician or veterinarian. Factors to consider include the condition being treated, the route of administration, the nature of the preparation, the weight of the mammal, the surface area, age and general condition, and the particular compound to be administered. However, the appropriate effective anti-tumor dose is in the range of about 0.1 to about 200 mg / kg body weight per day, preferably in the range of about 1 to about 100 mg / kg per day. The total daily dose can be administered as a single dose, multiple doses, e.g. 2- to 6 times daily or with an intravenous infusion for a fixed duration. Doses above and below the cited area above are within the scope of the present invention and can be administered to an individual patient if desired and necessary.

For example, for a 75 kg mammal, the dosage range should be about 75 to about 7500 mg daily, and the typical dose should be about 800 mg daily. If multiple doses are indicated, treatment of typically 200 mg of the compound of formula (I) may be given 4 times daily.

Preparations

The compositions of the present invention for medical use include the active compound, i.e. a compound of formula (I) together with its acceptable carrier and optionally other therapeutically active ingredients. The carrier must be pharmaceutically acceptable in that it is compatible with the other ingredients of the preparation and is not harmful to its recipient.

The present invention therefore further relates to a pharmaceutical composition comprising a compound of formula (I) together with a pharmaceutically acceptable carrier thereof.

The compositions include those suitable for oral, rectal, vaginal, transdermal or parenteral (including subcutaneous, intramuscular and intravenous) administration. Preferred are those suitable for oral or parenteral administration.

The compositions may be suitably presented in unit dosage form and may be prepared by any of the methods well known in the pharmaceutical art. All processes involve the step of bringing the active compound into contact with a carrier consisting of one or more additional ingredients. Generally, preparations are prepared by uniformly and carefully introducing the active compound into contact with a liquid carrier or a well-distributed solid carrier and then, if necessary, forming the product into the desired unit dosage form.

The compositions of the present invention suitable for oral administration may be presented as discrete units such as capsules, tablets or lozenges, each containing a predetermined amount of the active compound; as powder or granules; or a suspension or solution in an aqueous or non-aqueous liquid, e.g. syrup, elixir, emulsion or doses of liquid drug.

The tablet may be made by compression or molding, optionally with one or more additional ingredients. Compressed tablets may be prepared by compressing in an appropriate machine the active compounds in free-flowing form, e.g. powder or granules, optionally mixed with additional ingredients, e.g. binders, lubricants, inert diluents, surfactants or dispersants. The modeled tablets can be made by modeling in a suitable machine, a mixture of the powdered active compound with any suitable carrier.

The syrup or suspension can be made by adding the active compound to a concentrated, aqueous sugar solution, e.g. sucrose to which any additional ingredients can be added. Such additional ingredients may include flavors, a sugar crystallization inhibitor, or a solubility enhancer of any ingredient, e.g. as a polyhydric alcohol, e.g. glycerol or sorbitol.

Preparations for rectal or vaginal administration can be presented as suppositories with a conventional carrier, e.g. Cocoa Butter or Witepsol S55 (Trademark

Dynamite Nobel Chemical, Germany, for suppository bases).

For the transdermal administration of a compound of the present invention, it can be formulated as creams, gels, ointments or lotions or transdermal patches. Such compositions may e.g. formulate with an aqueous or oily base with the addition of suitable host, gelling, emulsifying, stabilizing, dispersing, suspending and / or coloring agents.

Formulations suitable for parenteral administration suitably include a sterile aqueous preparation of the active compound, which is preferably isotonic with the blood of the recipient. Such preparations suitably include a solution or suspension of a pharmaceutically or pharmacologically acceptable acid addition salt of a compound of formula (I) which is isotonic with the blood of the recipient. Thus, such preparations may suitably contain distilled water, 5% dextrose in distilled water or brine, and a pharmaceutically and pharmacologically acceptable acid addition salt of a compound of formula (I) having suitable solubility in these solvents, e.g. hydrochloride. Useful compositions also include concentrated solutions or solids containing a compound of formula (I) which, after dilution with a suitable solvent, give a solution suitable for parenteral administration above.

In addition to the aforementioned ingredients, the compositions of the present invention may further include one or more, optional additional ingredients useful in the art of pharmaceutical preparations, e.g. diluents, buffers, flavors, binders, surfactants, thickeners, lubricants, suspending agents, preservatives (including antioxidants) and the like.

EXAMPLES

The following examples illustrate aspects of the present invention but should not be construed as limiting. The symbols and conventions used in these cases are consistent with those used in modern chemical literature, e.g. Journal of the American Chemical Society. As used herein, the term room temperature means about 25 ° C.

Example 1

7-dimethylaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin (Compound 1) (A) 3,4-methylenedioxyacetanilide

To the commercially available 3,4-methylenedioxy aniline (17.0 g, 124 mmol) and sodium carbonate (15.5 g, 136 mmol) in chloroform (90 ml) at 5 ° C were added dropwise while stirring acetyl chloride (8.8 g, 124 mmol). The reaction mixture was allowed to warm to room temperature and stirring was continued for about 18 hours. The reaction mixture was washed twice with about 50 ml of 1 N HCl and the organic layer was dried (MgSO ₄ ) and the solvent removed to give a brown solid. Recrystallization from water by treatment with activated charcoal gave 3,4-methylenedioxyacetanilide (9.34 g, 42.1% of theory) as a light brown solid.

Elemental analysis: (C ₉ H ₉ NO ₃ )

% C % H % N Found: 60.34 5.04 7.79 Calc .: 60.33 5.06 7.82

(B) 2′-acetylamino-4 ′, 5′-methylenedioxy-2-chloroacetophenone

To a mixture of zinc chloride (24.3 g, 178.3 mmol) and chloroacetyl chloride (16.1 ml, 202.1 mmol) in nitromethane (85 ml) under nitrogen at room temperature, 3.4- methylenedioxyacetanilide (8.96 g, 50.0 mmol) in nitromethane (15 ml). This mixture was then heated at reflux for 1.5 hours, allowed to cool to room temperature, poured over ice, extracted with methylene chloride, which was then removed by evaporation to give a brown solid. This solid was recrystallized from ethyl acetate / hexane (including activated carbon treatment) to give 2'-acetylamino-4 ', 5'-methylenedioxy-2-chloroacetophenone (831.3 mg, 6.5% theoretical) as yellow crystals.

¹ H-NMR (CDCl ₃ ): δ 8.45 (s, 1H); 7.2 (s, 1H); 6.09 (s, 2H); 4.65 (s, 2H); 2.25 (s, 3H).

(C) 3,4-methylenedioxypivaloyl anilide

This compound was prepared by the procedure of Example l (a) except that an equivalent amount of 2,2-dimethylpropanoyl chloride was used instead of acetyl chloride.

(D) 2′-pivoylamino-4 ′, 5′-methylenedioxy-2-chloroacetophenone

This compound was prepared by the procedure of Example l (b) except that an equivalent amount of 3,4-methylenedioxypivaloyl anilide was used instead of 3,4-methylene dioxyacethanilide.

(E) 2′-amino-4 ′, 5′-methylenedioxy-2-chloroacetophenone

To 2'-acetylamino-4 ', 5'-methylenedioxy-2-chloroacetophenone (0.9 g, 3.53 mmol) or equivalent to 2'-pivoylamino-4', 5'-methylenedioxy-2-chloroacetophenone in ethanol ( 60 ml) at ca. 5 ° C was added dropwise conc. HCl (12.5 mL, 149.7 mmol). The reaction mixture was then heated at reflux for about 1 hour, then poured over 2 N NaOH / ice (80 ml / 60 g) and washed with ethyl acetate (3 x 70 ml). The organic portions were combined and washed with brine (50 ml), dried (anhydrous sodium sulfate) and concentrated in vacuo to give a greenish-yellow solid. This solid was recrystallized from ethyl acetate / isopropanol / hexane treated with activated carbon to give 2′-amino-4 ′, 5′-methylenedioxy-2-chloroacetophenone (0.39 g, 52% theory).

Elemental analysis: (C ₉ H _g NO ₃ Cl)

% C % H % N Found: 50.66 3.80 6.47 Calc .: 50.60 3.77 6.56

(F) 5 '- (R, S) -1,5-dioxo- (5'-ethyl-5'-hydroxy-2'H, 5'H, 6'H-6-oxoated) [3', 4 '-f] _A 6,8tetrahydroindolizine and 5' - (S) -1,5-dioxo- (5'-ethyl-5'-hydroxy-2'H, 5'H, 6'H-6-oxopyran) [ 3 ', 4'-f] _A 6,8-tetrahydroindolysin (Compounds of Formula (III)).

These compounds, hereinafter referred to as the tricyclic ketone (R, S) or. the tricyclic ketone (S) or together as a compound of formula (III) is prepared according to the procedure described by Wani et al., in '512. Note that the corresponding R enantiomer can also be prepared by the '512 process.

(G) 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin

Following the general procedure for camptothecin described in '512, 2'-amino-4', 5'-methylenedioxy-2-chloroacetophenone was stirred in refluxing toluene (50 ml) with tricyclic ketone (R, S) (256.3 mg, 0, 97 mmol) under Dean-Stark trap for half an hour. The reaction mixture was then cooled and the solid filtered and washed with toluene and ethanol to give 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin, (408.5 mg, 68.8%).

^χ Η-300 NMR (DMSO-D6): S 7.72 (s, 1H); 7.55 (s, 1H); 7.2 (s, 1H); 6.34 (s, 2H), 5.42 (s, 2H); 5.32 (s, 2H); 5.24 (s, 2H); 1.85 (m, 2H); 0.88 (t, 3H).

Nominal mass spectrum M + l:

Calc .: 441 Found: 441.

(H) 7-dimethylaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin

To a mixed mixture of 7-chloromethyl-10,11-methylenedioxy- (R, S) -camptothecin (0.11 g, 0.25 mmol) and potassium carbonate (346 mg, 0.5 mmol) in difmethylformamide (DMF) (1 ml) was added dimethylamine (6.1 ml, 0.5 mmol) as a 3.73 mg / ml solution in tetrahydrofuran at about 5 ° C. The reaction mixture was safely stopped, allowed to warm to room temperature, stirred for about 15 hours, and then filtered to remove solid material. The filtrate was concentrated by vacuum evaporation and the resulting solid was triturated with acetonitrile and filtered. The filtrate was concentrated by vacuum evaporation to a thick residue. The residue was dissolved in a minimum amount of chloroform and chromatographed on 30 g of flash grade silica gel, eluting successively with 250 ml of ethyl acetate, followed by 250 ml (9: 1 ethyl acetate, isopropanol), finally with 250 ml (4: 1 ethyl acetate, isopropanol). . The fractions were collected and observed by thin layer liquid chromatography (5% methanol, ethyl acetate) and visualized with a UV light. Appropriate fractions were combined, concentrated and dried under vacuum to give 7-dimethylaminomethylene-10,11-methylenedioxy (R, S) -camptothecin (6.0 mg, 4.7%). This compound is referred to as acetic acid salt. Tal. > 250 ° C

Elemental analysis: (C ^ H ^ NgOg.C ^ O ^

% C % H % N Found: 61.64 5.17 8.73 Calc .: 61.29 5.34 8.25

(I) shape of the open E ring.

The compound of part (H) is treated with an equivalent amount of sodium hydroxide to form the corresponding open E ring shape. Treating it with an equivalent amount of hydrochloric acid closes the E ring to re-form the compound of part (H).

Example 2

7-dimethylaminomethylene-10,11-methylenedioxy-20 (S) -camptothecin (Compound 2) (A) 7-chloromethyl-10,11-methylenedioxy-20 (S) -camptothecin

This compound is prepared by the method of Example 1, except that in part (G) an equivalent amount of tricyclic ketone (S) is used instead of the tricyclic ketone (R, S).

Tal. > 250 ° C.

(B) 7-dimethylaminomethylene-10,11-methylenedioxy-20 (S) -camptothecin

This compound is prepared by the method of Example 1, part (H), except that an equivalent amount of 7-chloromethyl-10,11-methylenedioxy-20 (S) -camptothecin prepared according to example 2, part (A) is used instead of 7-chloromethyl -10,11-methylenedioxy-20 (R, S) camptothecin.

Tal. > 250 ° C

Nominal mass spectrum M + l:

Calc .: 450 Found: 450

Example 3

7-dimethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin (Compound 3) (A) 7-chloromethyl-10,1 l-ethylenedioxy-20 (R, S) -camptothecin

This compound is prepared by the method of Example 1, except in parts (A) and (C) an equivalent amount of 3,4-ethylenedioxy aniline is used instead of 3,4-methylenedioxy aniline. High resolution mass spectrum M + l:

calc .: 455.1009 found: 455.1005 (B) 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin

This compound was prepared by the method of Example 1, part (H), except that an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin was used instead of 7-chloromethyl-10,1 l-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 464.1821 Found: 464.1833

Example 4

7-dimethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin (Compound 4) (A) 7-chloromethyl-10,11-ethylenedioxy-20 (S) -camptothecin

This compound is prepared by the method of Example 1, except that in parts (A) and (C) an equivalent amount of 3,4-ethylenedioxy analine is used instead of 3,4-methylenedioxy aniline and in part (G) an equivalent amount of tricyclic ketone (S) instead of the tricyclic ketone (R, S).

High resolution mass spectrum M + l:

calc .: 455.1009 found: 455.1000 (B) 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin

The compound is prepared by the procedure of Example 1, part (H), except that an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (S) -camptothecin is used instead of 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 464.1821 Found: 464.1811.

Example 5

7-morpholinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin (Compound 5)

Use the same procedure as in example 1, part (H), except to use an equivalent amount of morpholine instead of dimethylamine, and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin prepared according to example 3, part (B) instead of 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 506.1942 Found: 506.1925.

Example 6

7-morpholinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin (Compound 6)

Use the same procedure as in Example 1, part (H), except to use an equivalent amount of morpholine instead of dimethylamine, and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (S) -camptothecin prepared according to example 4, part (B ), instead of 7-chloromethyl-10.1 l-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 506.1942 Found: 506.1929.

Example Ί

7-pyrrolidinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin (Compound 7)

Use the same procedure as in example 1, part (H), except to use an equivalent amount of pyrrolidine instead of dimethylamine and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin prepared as in example 3, part (A) instead of 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

calcd .: 490.1978 found: 490.1988.

Example 8

7-piperidinomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin (Compound 8)

Use the same procedure as in Example 1, part (H), except to use an equivalent amount of piperidine instead of dimethylamine.

Nominal mass spectrum M + l:

Calc .: 490 Found: 490 ¹ H-300 NMR (DMSO-d6): δ 7.95 (s, 1H); 7.62 (s, 1H) 7.29 (s, 1H); 6.35 (s, 2H); 5.49 (s, 2H); 5.41 (s, 2H); 4.85 (broad s, 2H); 1.9-0.7 (m, 11H).

Example 9

7-piperidinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin (Compound 9)

Use the same procedure as in example 1, part (H), except to use an equivalent amount of piperidine instead of dimethylamine and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin prepared according to example 3, part (A) instead of 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 504.2127 Found: 504.2129.

Example 10

7- (4-methylpiperazinomethylene) -10,11-ethylenedioxy-20 (R, S) -camptothecin (Compound 10)

Use the same procedure as in Example 1, part (H), except to use an equivalent amount of 4-methylpiperazine instead of dimethylamine and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin prepared according to example 3 , part (A) instead of 7-chloromethyl-10, 11-methylenedioxy-20 (R, S) -camptothecin.

High resolution mass spectrum:

Calc .: 519.2236 Found: 519.2246.

Example 11

7- (4-methylpiperazinomethylene) -10,11-ethylenedioxy-20 (S) -camptothecin (Compound 11)

Use the same procedure as in example 1, part (H), except to use an equivalent amount of 4-methylpiperazine instead of dimethylamine and an equivalent amount of 7-chloromethyl-10,11-ethylenedioxy-20 (S) -camptothecin prepared according to example 4, part ( A) instead of 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin.

M.p .: 261-264 ° C.

Nominal mass spectrum M + 1:

Calc .: 519 Found: 519.

Example 12

Pharmaceutical preparations (A) Transdermal system

Ingredients Amount of active compound 600.0 mg silicone fluid 450.0 mg colloidal silica 25.0 mg

The silicone fluid and the active compound are mixed together and digested with colloidal silica to increase the viscosity. This material is then dosed into a post-hot sealed polymer laminate comprising the following: a polyester withdrawal strip, a skin contact adhesive composed of silicone or acrylic polymers, a control membrane which is polyolefin (eg polyethylene), polyvinyl acetate or polyurethane, and first impermeable to the membrane made of polyester multilaminate. The system described is a 10 cm ² large patch.

(b) Oral tablet

Ingredients Amount of active compound 200.0 mg starch 20.0 mg magnesium stearate 1.0 mg

The active compound and starch were granulated with water and dried. Magnesium stearate is added to the dried granules and the mixture is well mixed. Compress the mixed mixture into a tablet.

(C) A candle

Ingredients Amount of active compound 150.0 mg theobromine sodium salicylate 250.0 mg

Witepsol S55 1725.0 mg

Ineffective ingredients are mixed and dissolved. The active compound was then partitioned into a molten mixture, poured into molds and allowed to cool.

(D) Injection

Ingredients Amount of active compound 20.0 mg buffering agents q.s.

propylene glycol 0.4 water for injection 0.6 ml \

The active compound and the buffering agents are dissolved in propylene glycol at about 50 ° C. After stirring, water is added for injection and the resulting solution is filtered, filled into an ampoule, sealed and sterilized by autoclaving.

(E) Capsule

Ingredients Amount of active compound 200.0 mg lactose 450.0 mg magnesium stearate 5.0 mg

The well-ground active compound is mixed with lactose and stearate and filled into a gelatin capsule.

For

Glaxo Inc:

ΡΑΪΕΝΤΝΑ IUSARBA

LUU8L ^ XNA «

Claims (20)

Compounds of formula (I) wherein: n represents an integer 1 or 2; and i) R ¹ and R ² independently represent hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl; ii) R ¹ represents hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl, and R ² represents-COR ³ where: R ³ iii) represents hydrogen, lower alkyl, perhalo-lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or R ¹ and R ² taken together with the binding nitrogen form a saturated heterocyclic group of 3 to 7 atoms of formula (IA) (IA) where: Y represents O, S, CH ₂ or NR ⁴ where: R ⁴ represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted with one or more groups lower alkyl, halogen, nitro, amino, lower alkyl amino, perhalo lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or -COR ^{4 5} where: R ⁵ represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, perhalo-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups; and pharmaceutically acceptable salts and solvates thereof. Compounds according to claim 1, wherein said lower alkyl (C 1 _M ) is alkyl, said lower alkoxy (C ₁₄ ) alkoxy and said lower alkenyl (C 1-6 alkenyl). Compounds according to claim 1 or claim 2, characterized in that: R ¹ and R ² taken together form a heterocyclic group selected from the groups consisting of aziridine, azetidine, pyrrolidine, piperidine, hexamethylenimine, imidazolidine, pyrazolidine, isoxazolidine, piperazine, N-methylpiperazine, homopiperazine, N-methylthiazolidine, N-methylthiazolidine morpholine or thiomorpholine. Compounds according to any one of claims 1 άσ3, characterized in that n represents an integer 1 or 2; and i) R ¹ and R ² independently represent hydrogen, lower alkyl or hydroxy lower alkyl; ii) R ¹ represents hydrogen and R ² represents -COR ³ where R ³ represents perhalonyl alkyl; or iii) R ¹ and R ² taken together with the binding nitrogen form azetidine, pyrrolidine, piperidine, morpholine, thiomorpholine or piperazine, optionally N-substituted with lower alkyl, phenyl; phenyl substituted by one or more trans-lower alkyl or lower alkoxy groups; or -COR ⁵ , wherein R ⁵ represents lower alkoxy. 5. A compound characterized in that it is selected from the group consisting of: 7-dimethylaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin, 7-dimethylaminomethylene-10,1 l-methylenedioxy-20 (S) -camptothecin, 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-dimethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-morpholinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-morpholinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-pyrrolidinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-piperidinomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin, 7-piperidinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7- (4-methylpiperazinomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7- (4-methylpiperazinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-diethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-diethylaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-diethylaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-N-methylethanolaminomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin, 7-N-methylethanolaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-diethanolaminomethylene-10,11-ethylenedioxy-20 (R, S) -camptothecin, 7-diethanolaminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-azetidinomethylene-10,11-methylenedioxy-20 (R, S) -camptothecin, 7-azetidinomethylene-10,11-methylenedioxy'20 (S) -camptothecin, 7-thiomorpholinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-azetidinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin, 7-4-methylpiperazinomethylene-10,11-methylenedioxy-20 (S) -camptothecin, 7-Trifluoroacetaniidoiiethylene-10,1 l-ethylenedioxy-20 (S) -camptothecin, 7-Trifluoroacetamidomethylene-10,11-methylenedioxy-20 (S) -camptothecin, 7-aminomethylene-10,11-ethylenedioxy-20 (S) -camptothecin dihydrochloride, 7-Aminomethylene-10,11-methylenedioxy-20 (S) -camptothecin dihydrochloride, 7-tert-butyloxycarbonyl-piperazinomethylene-10,11-ethylenedioxy-20 (S) camptothecin, 7-piperazinomethylene-10 salt, 11-ethylenedioxy- (S) -camptothecin and trifluoroacetic acid, 7- (a, a, a-Trifluoro-m-tolyl) -piperazinomethylene-10,11-ethylenedioxy-20 (S) camptothecin, 7- (2-methoxyphenyl-piperazino) methylene-10,11-ethylenedioxy-20 (S) -camptothecin, and 7-Phenylpiperazinomethylene-10,11-ethylenedioxy-20 (S) -camptothecin. and pharmaceutically acceptable salts and solvates thereof. Compounds according to any one of claims 1 to 4, characterized in that they are in the S configuration. 7. A compound of formula (Γ) HO 'o O where n represents an integer 1 or 2; and R ^1a and R ²³ represent: i) independently hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl, or ii) taken together with the binding nitrogen to form a heterocyclic group of 3 to 7 atoms of formula (IA ') (IA') wherein Y ^a represents O, S, CH ₂ , NH or N (lower alkyl), and pharmaceutically acceptable salts thereof. A compound according to any one of claims 1 to 7 for use in treatment. A pharmaceutical composition comprising the compound of claim 1 or a pharmaceutically acceptable salt or solvate thereof, together with a pharmaceutically acceptable carrier. A method for inhibiting a topoisomerase I enzyme enzyme, characterized in that said enzyme is contacted with an effective topoisomerase I inhibitory amount of a compound according to any one of claims 1 to 7. Use of a compound according to any one of claims 1 to 7 in the preparation of a medicament for use in the treatment of tumors. A process for the preparation of a compound of formula (I) as defined in claim 1 or its physiologically acceptable salts or solvates, characterized in that (a) the compound of formula (IV) is metabolized X Oh HO 'where X is halogen, with a compound of formula (V) HNIVR ² (V) wherein R ¹ and R ² are as defined for a compound of formula (I); or (b) react the compound of formula (Ha) NR ¹ R ² / O (CH ₂ ) _n (Ha) wherein R ¹ and R ^{2 are} as defined for a compound of formula (I), with a compound of formula (III) HO 'd and if it is necessary and / or desired to expose the compound thus obtained to one or more further reactions involving: (i) converting the resultant compound of formula (I) or its salt or protected derivative to another compound of formula (I) and / or (ii) removing any protecting groups or groups and / or (iii) converting the compound of formula (I) or a salt thereof into a physiologically acceptable salt or solvate thereof. A compound as defined in any one of claims 1 to 7, characterized in that it is of the R configuration. A compound as defined in any one of claims 1 to 7, characterized in that the E ring is open. 15. A compound of formula (IV) X Oh HO 0 where n is 1 or 2 and X is halogen. 16. A compound characterized in that it is selected from the group consisting of: 7-chloromethyl-10,11-methylenedioxy-20 (R, S) -camptothecin, 7-chloromethyl-10,11-methylenedioxy-20 (S) -camptothecin, 7-chloromethyl-10,11-ethylenedioxy-20 (R, S) -camptothecin and 7-chloromethyl-10,11-ethylenedioxy-20 (S) -camptothecin. A method for inhibiting a topoisomerase I enzyme, wherein said enzyme is contacted with an effective topoisomerase I inhibitory amount of a compound according to claim 15 or claim 16. A compound of formula (IIA) wherein: n represents an integer 1 or 2; and i) R ¹ and R ² represent hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl; ii) R ¹ represents hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl, and R ² represents -COR ³ where: R ³ iii) represents hydrogen, lower alkyl, perhalo-lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or R ¹ and R ² taken together with the binding nitrogen form a saturated heterocyclic group of 3 to 7 atoms of formula (LA) (IA) '42 'where: Y represents O, S, CH ₂ or NR ⁴ where: R ⁴ represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted with one or more groups lower alkyl, halogen, nitro, amino, lower alkyl amino, perhalo lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or -COR ⁵ , where: R ⁵ represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, perhalo-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups. A compound according to claim 18, characterized in that R ¹ and R ² taken together form a heterocyclic group selected from the group consisting of aziridine, azetidine, pyrrolidine, piperidine, hexamethylenimine, imidazolidine, pyrazolidine, isoxazolidine, piperazine, N- methylpiperazine, homopiperazine, N-methylhomopiperazine, thiazolidine, isothiazolidine, morpholine or thiomorpholine. A compound of formula (II) (II) wherein n is an integer 1 or 2 and X is halogen, 22730-IV-93-KA SUMMARY Water soluble camptothecin derivatives The present invention relates to water-soluble camptothecin derivatives of formula (I) wherein: n represents an integer 1 or 2; and i) R ¹ and R ² independently represent hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy lower alkyl; ii) R ¹ represents hydrogen, lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl or lower alkoxy lower alkyl, and R ² represents -COR ³ where: R ³ represents hydrogen, lower alkyl, perhalo-lower alkyl, (C _{3 7} ) cycloalkyl, (C _{3 7} ) cycloalkyl lower alkyl, lower alkenyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or iii) R ¹ and R ² taken together with the binding nitrogen form a saturated heterocyclic group of 3 to 7 atoms of formula (IA) wherein: (, _A) Y represents O, S, 0¾ or NR ⁴ where: R ⁴ represents hydrogen, lower alkyl, perhalo-lower alkyl, aryl, aryl substituted with one or more groups lower alkyl, halogen, nitro, amino, lower alkyl amino, perhalo lower alkyl, hydroxy lower alkyl, lower alkoxy, lower alkoxy lower alkyl; or -COR ⁵ , where: R ⁵ represents hydrogen, lower alkyl, perhalo-lower alkyl, lower alkoxy, aryl, aryl substituted with one or more lower alkyl, perhalo-lower alkyl, hydroxy lower alkyl, lower alkoxy lower alkyl groups; and pharmaceutically acceptable salts thereof; their use in the treatment of tumors and the procedures for their preparation.