LU85607A1 - DRUGS BASED ON 1,2-DITHIOLANE DERIVATIVES - Google Patents

Description

% * *

The present invention relates to the use in therapy of derivatives of 1,2 dithiolane.

The invention relates more particularly to the therapeutic use of the compounds of formula I

(i) S — s i 0 10 in which

R1 represents a hydroxy, lower alkoxy, amino, cycloalkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino group in which the alkyl radicals are unsubstituted or substituted by an aryl, heteroaryl or cycloalkyl and, n means an integer between 0 and 10.

! The compounds of formula I can, depending on the case, also be in the form of salts when R 1 represents a hydroxy group or a basic group, in particular an optionally substituted amino group as specified above. The invention therefore includes the therapeutic use of the compounds of formula I in free form or, as the case may be, in the form of a pharmaceutically acceptable salt.

The compounds of formula I and, depending on the case, their salts, will be designated in the remainder of this description "the compounds of the invention".

Various free acids and alkyl esters and salts of these compounds are known, for example from Tetrahedron Letters 13, 1073-5 (1973); Arch. Biochem. Biophys. 185, 576-83, (1978); ü.

30 Org. Chem. 40, 58-62 (1975); Arkiv. Kemi. 25 (14-4), 263-77 (1966); Japanese published patent application 49/117616, as is 6,8-dithiooctanamide monooxide (see Japanese patent application JP Kokoku 10931/64). These documents however do not mention | no therapeutic use of these compounds.

ί t ί ί!;

V

2

The Applicant has now surprisingly found that the 1,2-dithiolans of the invention have valuable pharmacological properties, in particular an immunostimulating activity as described below.

Among the compounds of formula I, the compounds of formula; ïp jw {ew "j · s— i (ip)" i in which R'i represents a cycloalkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino group in which the alkyl radicals are non substituted or substituted by an aryl group,: heteroaryl or cycloalkyl and n signifies an integer between 0 and 10, and their salts, are new compounds. They are also part of the present invention as well as their method of preparation.

The compounds of formula Ip constitute a preferred group of the compounds of formula I.

According to the process of the invention, the compounds of formula Ip can be obtained by oxidation of a corresponding compound of formula IIp 25 W (CH?) N-C0Ri 'O 2 "' (IIP)

S — S

In which R'i and n are as defined above.

The process of the invention can be carried out using the usual oxidation processes, for example using m-chloroperbenzoic acid. The reaction can be carried out in an inert solvent, for example a chlorinated hydrocarbon such as dichloromethane, preferably at low temperature, for example under cooling by ice. The final product can be isolated and purified according to the usual methods.

The other compounds can be prepared analogously or for example as described in the literature mentioned above.

The compounds of formula I can be in the form of syn or anti isomers and in the form of optical isomers. The mixtures originating from their preparation can be separated according to the usual methods, for example by chromatography.

When the compounds are in a particular isomeric form, this will be mentioned.

Among the compounds of formula IIp, the compounds of formula IIpA are new and also form part of the invention. These compounds can be prepared as follows:

^> (CH2) nC00H

s — s IV

20} S

^ (CH2) n.C00-N I III

SS ° • 1 + HN-R3 ^ <CH2) n-co - <^ HP * S — s in which R2 and R3 each represent, independently of one another, a cycloalkyl group or an unsubstituted alkyl group or substituted by a cycloalkyl, heteroaryl or aryl group and one of the symbols R2 and R3 may additionally represent hydrogen.

ï 4

These two processes can be carried out according to the usual methods, for example as described below in the examples. The compounds of formula III are also new and also form part of the invention.

The other intermediates are known or can be prepared analogously to known methods.

The intermediate products can be isolated and purified according to the usual methods or, when appropriate, be directly subjected to the subsequent reaction.

The lower alkyl radicals preferably contain from 1 to 4 carbon atoms, especially 1 or 2 carbon atoms. The aryl group means, for example, a phenyl group which may be substituted or preferably unsubstituted. The heteroaryl group preferably means a heterocycle which may optionally be condensed to a benzene ring which may itself be unsubstituted or substituted. As an example of a substituent, mention may be made of the alkoxy group. Cycloalkyl groups preferably contain 3 to 10 members, especially 6 to 8 members, n preferably means an even number especially 0, 2 or 4.

It has now surprisingly been found that the compounds of the invention exert an immunostimulatory activity.

More particularly, it has been found that these compounds stimulate not only lymphocyte proliferation in response to antigens, but also the production of antibodies (primary and secondary immunoresponse) as well as cell-mediated immunoresponse.

The immunostimulatory activity of the compounds in question can be shown in conventional tests in vitro and in vivo. Thus, the positive immunostimulatory activity can be shown for the compounds of the invention, for example in the following tests: IN VITRO: TEST I: Mishell / Dutton test - development of a humoral response by primary immunization of spleen cells 10 of mice with regard to heterologous red blood cells, in suspension cultures [Science 153, 1004 (1966) and 0. Exp. Med. 126 ^ 423 (1967) 3.

Mouse spleen cells are grown for 3 to 4 days in the presence of the antigen (sheep erythrocytes, GRM) and the test substance. The cells are collected, washed = and placed on plates with fresh antigen (GRM) in semi-solid agar. After incubation for 60 minutes, the complement is added and incubation is continued for another 90 minutes. Sensitization of mouse lymphocytes to the anti-gene during primary culture results in release of antibodies. In the presence of the complement and of the secret antibody specific to GRM, the sheep erythrocytes will therefore be lysed (plaque formation). Stimulation of plaque forming cells is observed using the compounds of the invention at a concentration of 0.01 to 10.0 pg / ml.

TEST II: Mixed lymphocyte reaction - [J.F. Bach et al., J. Exp. Med. 135, 1430 (1972) 3 The reaction, i.e. proliferation and differentiation of lymphocytes [mouse spleen cells 30 (Balb / c) 3 by co-incubation for days with allogeneic spleen cells 6 of irradiated mice (CBA ^), is measured in the presence and in the absence of the substance to be tested. The reaction in the absence of the test substance serves as a control and is considered to be 100¾. The reaction in the presence of the substance to be tested is expressed as the change in%, compared to the control reaction 100¾. Reaction stimulation is observed using the compounds of the invention at a concentration of 0.4 to 10 μg / ml "1. TEST III: Humoral immune response secondary to" dinitrophenyl-keyhole 1 impet hemocyanin "(DNP-KLH), T cell specific antigen 10

Three weeks after immunization with DNP-KLH, the mice receive a booster injection of the same antigen. The spleens of the animals are removed one to four weeks after "challenge" and a cell culture is prepared. The specific antibodies developed in response to the DNP-KLH antigen are recovered from the supernatant and measured according to the ELISA technique. The test is added at various concentrations during the in vitro incubation of the cell culture. The development of antibodies in the absence of the test substance is used as a control and is taken as a 100% reaction. The reaction in the presence of the test substance is expressed as the change in% reaction, compared with the 100% control reaction.

Reaction stimulation (immune response) is observed using the compounds of the invention at a concentration of 0.4 to 10 μg / ml.

TEST IV: Stimulation of the production of immune interferon induced by antigens From lynphocytes [mouse spleen cells (Balb / c) 3 are co-incubated for 5 days with alΙοί 30 gene spleen cells from irradiated mice (CBA ^) , analogously i 7 to test II above, in the presence or absence of the substance to be tested. The supernatants are collected and examined for their immune interferon content (protection of virus-infected L929 fibroblasts), the interferon units measured being normalized using a human leukocyte interferon preparation of known activity.

A stimulation of the production of immune interferon is observed in the above test, using the compounds of the invention at a concentration of approximately 0.2 to 5.0 μg / ml.

10 IN VIVO: TEST V: Delayed type hypersensitivity reaction test (cell-mediated immunity) - [Dietrich et al., Int. Arch. Allergy 38, 246 (1970) 3.

{* Mice are sensitized topically by brushing the abdomen with the antigen (oxazolone) on day 0. The test substance is administered intraperitoneally or by! orally on each of the following 5 days. The dose of antigen causing the reaction is applied on the 9th day by brushing the right ear. The thickness of the skin of the right ear and of the left ear untreated is measured 24 hours later using a micro-compass to calibrate. The average difference in thickness between the two ears is used as a parameter to assess the reaction. Pronounced stimulation of the delayed-type hypersensitivity reaction is observed in healthy adult mice having a normal immune response, after administration of the compounds of the invention at a daily dose of 0.1 to 10 mg / kg for 5 days, intraperitoneally or orally.

TEST VI: Jerne test - development of a humoral response (test for cells forming hemolysis plaques] 30 - [Jerne et al., "Cell Bound Antibodies" (ed. Amos and

Koprowski), Wistar Inst. Press., Philadelphia, U.S.A. pp. 109-12213.

Mice are sensitized by intravenous injection dj 28 of sheep erythrocytes (GRM), and the test substance is administered intraperitoneally on day 0. After 4 to 10 days the mice are sacrificed and a suspension of spleen cells. The cell suspension is placed on plates, together with fresh antigen (GRM), in semi-solid agar and is incubated for 2 1/2 hours in the presence of the complement. The sensitized lymphocytes secrete antibodies in response to the antigen and, in the presence of the complement, the antigen (GRM) is lysed (plaque formation).

Administration of the compounds of the invention at a dose of 0.1 to 1.0 mg / kg results in an increase in IgM antibodies as well as IgG antibodies.

TEST VII: Activation of natural K cells

The test substance is administered intraperitoneally or orally to nude (athymic) mice (Balb / c or C57 / BL). After 16 hours the spleens of the animals are removed and the spleen cells incubated for 4 hours with target cells labeled with chromium (YAK-1). Natural K cells destroy the target cells, releasing the labeled chromium in the supernatant. The supernatant is collected and the quantity of chromium released · is measured using a scintillation counter.

The release from target cells incubated with spleen cells from untreated mice serves as a control and is considered to be 100¾. The release after administration of the test substance is expressed as the change in% of release, compared to the control.

An increase in the release of chromium is observed following the administration of the compounds of the invention at doses of 0.1 to 10.0 mg / kg.

The compounds of the invention are therefore indicated for use as immunostimulants, for example as immunological adjuvants, as systemic immunopotentiators and as stimulants of non-specific resistance of the host. The compounds are therefore indicated, for example, for treatment or adjunctive therapy (i.e. in combination with another specific or adjuvant therapy) of conditions associated with a weakened immune response, especially a response humoral and / or reduced delayed type hypersensitivity, and conditions where an increased immune response is indicated · In particular, the compounds of the invention are indicated for the treatment or adjunct treatment of disease states originating from idiopathic immune deficiencies or as they occur in senescent patients and patients with severe burns or generalized infections. The compounds of the invention are also indicated for the treatment or adjunctive treatment of viral diseases (such as disseminated herpes, progressive vaccinia and disseminated chickenpox) as well as Hodgkins disease and other malignant tumors.

For the therapeutic uses mentioned above, a dose indicated orally is from about 0.1 mg to about 70 mg, administered at one time for an adjuvant effect, for example in the adjunct treatment, or daily. , the administration in the latter case advantageously being carried out in divided doses 2 to 4 times per day or in a delayed-release form. The unit doses indicated for administration by oral route consequently comprise from approximately 0.025 mg to approximately 35 mg of active ingredient, when • daily administration is desired, or up to 70 mg of active ingredient, when single adjuvant therapy is desired.

Due to their immunostimulatory activity, the compounds of the invention are also indicated as adjuvants for vaccines.

10

For this use, an oral dose is 0.5 mg to 100 mg, preferably about 70 mg, administered on the day of vaccination with a booster at the same dose 2 to 4 weeks later.

The compounds of formula I in which represents a hydroxy or amino group, can be used in free form or in the form of pharmaceutically acceptable salts, the latter having the same order of activity as the free forms.

The compounds can be administered orally, or parenterally, for example in a form suitable for injection.

The pharmaceutical compositions comprising the compounds of the invention can be prepared according to conventional pharmaceutical methods, for example by admixture with usual pharmaceutical diluents, vehicles or other excipients. Such pharmaceutical compositions are advantageously presented, for example, in the form of tablets or capsules or in a form suitable for injection.

In accordance with the above, the present invention also relates to a compound of formula I, in free form or, as the case may be, in the form of a pharmaceutically acceptable salt, for use as a medicament, in particular for use as a immunostimulant, especially for use in treatment or adjunct therapy, for example of conditions associated with a weakened immune response as indicated above.

The invention also relates to a medicament comprising, as active principle, a compound of formula I in free form or, as the case may be, in the form of a pharmaceutically acceptable salt.

According to another aspect, the invention also relates to a pharmaceutical composition comprising a compound of formula I, in free form or, as the case may be, in the form of a pharmaceutically acceptable salt, together with a pharmaceutically acceptable diluent or vehicle.

Among the compounds of the invention, the compounds of formula Ip are particularly interesting.

The preferred meanings of the substituents are as follows:

Rl * a) OH, OAlk or NH2, 5 b) NH-alkyl, c) N (alkyl) 2, d) a substituted monoalkylamino group, e) an NH-CH2U group or 2) -phenyl, -cycloalkyl, -heteroaryl bicyclic, 10 n = a) an even number b) 0, 2 or 4, c) 0, CORi position a) 3 or 5 15 b) 4.

A particular group of compounds includes those of formula Ip, wherein R'i represents a monoalkylamino group substituted by a cycloalkyl, phenyl or bicyclic heteroaryl group, the latter two groups being unsubstituted or substituted by an alkoxy group; or a cycloalkylamino group and n signifies 0.

Another group of igneous compounds of formula 1, in which R 1 represents a hydroxy, amino, mono- (lower alkyl) -amino group, di- (lower alkyl) -amino, lower alkoxy or MeO, in which Me represents an equivalent of metal and the alkyl radicals are unsubstituted or substituted by an aryl group and n signifies an integer from 0 to 10. Among this group, the compounds in which R 1 has a meaning other than hydroxy are preferred,

MeO, lower alkoxy or amino.

In each of the groups of compounds above, the group 30 carrying R 1 is preferably located in position 4.

For the use indicated above, the compounds are preferably in anti form.

12

A particularly preferred compound is the anti-N-cyclohexylmethyl-1,2-dithiolane-4-carboxamide 1-S-oxide.

The following examples illustrate the invention without in any way limiting its scope. In these examples, the temperatures 5 are indicated in degrees Celsius.

Example 1: 1-S-oxide of svn- and anti-N-3,4-dimethoxybenzyl-1,2,2-thiolane-4-carboxamide

0.3 g of verarrylamide of asparagu-sic acid (1,2-dithiolane-4-carboxylic acid) is dissolved in 15 ml of anhydrous dichloro-10 methane and the mixture is cooled with an ice bath.

0.21 g of m-chloroperbenzoic acid dissolved in 15 ml of anhydrous dichloromethane is then added. After one hour, the reaction mixture is stirred with a sodium bicarbonate solution, dried over anhydrous magnesium sulfate and evaporated. The crystalline residue is taken up in a little dichloromethane and the mixture is separated on a column at medium pressure (Merck LiChroSorb Si60, dimension C; eluent: ethyl acetate).

Syn isomer: Rf = 0.23, F = 164-166 *

Anti isomer: Rf = 0.35, F = 191-193 *.

The following compounds can be obtained in a similar manner to that described in Example 1 (the "position" column indicates the fixing point of the side chain; the Rf values are measured in a toluene / ethyl acetate mixture * 1 / 1).

13

Ex. ___ Po ", j} _ F__Rf: 2 -NH.CH2— / h) 4 0" yn 103-105 · ^ - anti 131-133® 5 3 -NH.CH2.C2.H5 4 0 syn 99-103® anti 161-163® 4 -NH— / h X- 4 0 syn 139-144® 0.18 * - anti 179-180® 0.25 5 -NH.CH2_ / \ 4 0 “yn syrup 0.16 anti syrup 0.28 OCJL, 6 -NH.CH, CH, --- 3 4 0 "yn 125-145® 0.44 15 2 Z η η.

Λ anti 198-201® 0.51 H * 7 3 0 syn 131-134 ° c> —f anti 139-141 ° 20-1 ---

The starting materials can be prepared as follows: A. Veratrylamide of asparaqusic acid a) Ester of asparagusic acid with N-hydroxysuccinimide A 0.32 g of asparagusic acid dissolved in 20 ml of anhydrous dich! Oromethane , 0.62 g of di- (N-succinimidyl) carbonate, 0.3 ml of pyridine and 1 g of anhydrous magnesium sulfate are added. The mixture is heated to 50 * with nitrogen sweep and heated to reflux with stirring for 3 hours. The reaction mixture is then allowed to cool, the magnesium sulphate is removed by filtration and the filtrate is evaporated. The residue is purified on a column at medium pressure (Merck LiChroSorb Si60, dimension C, eluent: toluene / ethyl acetate = 1/1, Rf B 0.56), F = 129 *.

b) Veratrylamide of asparagusic acid

0.062 g of the asparagusic acid ester 5 is dissolved with the N-hydroxysuccinimide in 5 ml of anhydrous dichloromethane to which 0.112 g of veratrylamine is then added at room temperature. After 20 minutes, the reaction mixture is evaporated and it is purified on a column at medium pressure (Merck LiChroSorb Si60, dimension A; eluent: toluene / ethyl acetate = 1/1; Rf = 0.32), F = 154 *.

By following a similar procedure, the following starting materials can be obtained (the "position" column indicates the fixing point of the side chain).

15 Rx Poe. n F

B -NH.CH2- / H 4 O 119 * 123® 20 C -NH.CH2.C6H5 4 O 120-123® D -NH— / h) 4 0 159-160® 25 E -NH.CH2— / \ 4 0 73-74 ° F -NH.CH-CHL- - OCH, 4 0 Syrup 30 2 2 h il | 3 G -NH.CH2./h \ 100-103 ° 35 ---- 15 Other compounds which can be used according to the invention are for example those, of formula I described in the abovementioned literature such as 1-S-oxide of syn- and anti-1,2-dithiolane-3-carboxylic acid (respectively F * 115-7 * 5 and 148 'with decomposition) and 1-S-oxide of syn acid - and anti-1,2-dithiolane-4-carboxylic (respectively F »130-140 * and 130-136 *).

Claims (13)

16 1. The therapeutic use of 1,2-dithiolane derivatives of formula I 5 / V (CH2> n-C0Rl Π (I) S — 5 0 in which 10 R 1 represents a hydroxy, lower alkoxy, ami no, cyclo-alkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino group in which the alkyl radicals are unsubstituted or substituted by an aryl, heteroaryl group or cycloalkyl and. 15. means an integer between 0 and 10, in free form or, as the case may be, in the form of a pharmaceutically acceptable salt. 2. A medicament, characterized in that it contains, as active ingredient, a 1,2-dithiolane derivative of formula I 20 fl (i) s — s ί 0 25 in which R1 represents a hydroxy, lower alkoxy group, amino, cycloalkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino in which the alkyl radicals are unsubstituted or substituted by an aryl, heteroaryl or cycloalkyl group and n signifies an integer between 0 and 10, in free form or, as the case may be, in the form of a pharmaceutically acceptable salt. * 17 " 3. A pharmaceutical composition, characterized in that it contains a compound of formula I 5 ΓΊ (I) S — S 1 0 in which R 1 represents a hydroxy, lower alkoxy, amino, cyclo-alkyl friend no or mono group - (lower alkyl) -amino or di- (lower alkyl) -amino in which the alkyl radicals are unsubstituted or substituted by an aryl, heteroaryl or cycloalkyl group and, n signifies an integer between 0 and 10, 15 in the form free or, as the case may be, in the form of a pharmaceutically acceptable salt, together with a pharmaceutically acceptable diluent or vehicle. 4. A pharmaceutical composition according to claim 3, characterized in that R 1 represents a cycloalkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino group in which the alkyl radicals are unsubstituted or substituted by a aryl, heteroaryl or cycloalkyl group and n signifies an integer between 0 and 10. 5. A compound of formula Ip 25 w'WV s—] (IP) l in which ^ R'i represents a cycloalkylamino or mono- (lower alkyl) -amino or di- (lower alkyl) -amino group in which the alkyl radicals are unsubstituted or substituted by an aryl, heteroaryl or cycloalkyl group and, n signifies a number whole between 0 and 10, 35 in free form or in the form of a salt. ¥ 18 6. A compound according to claim 5, characterized in that the meaning of R'i is chosen from the following: a) NH-alkyl, b) N (alkyl) 2, 5 c) a substituted monoalkylamino group, d) a NH-CH2 (1 or 2) -phenyl, -cycloalkyl, -heteroaryl bicyclic group, and / or the position of the group containing R'i is chosen from the following: 10 a) 3 or 5 b) 4 and / or n is chosen from a) an even number - b) 0, 2 or 4,. C) 0, in free form or in the form of a salt. 7. The anti-N-cyclohexylmethyl-1,2-di-thiolane-4-carboxamide 1-S-oxide and its salts. 8. A compound chosen from 1-S-oxide of anti-N-20 3,4-dimethoxybenzyl-1,2-dithiolane-4-carboxamide, 1-S-oxide of anti-N-benzyl-1,2 -dithiolanne-4-carboxamide, the 1-S-oxide of anti-N-cyclohexyl-l, 2-dithiolanne-4-carboxamide, 1-S-oxide of anti-N-cyclooctyl-l, 2-dithiolanne-4 -carboxamide, the 1-S-oxide of anti-N- (5-methoxy-indole-3-yl) -1, 2-dithiolane-4-carboxamide and the 1-S-oxide of anti-N-cyclohexylmethyl- 1,2-dithiolane-3-carboxamide and their salts. 9. A process for the preparation of a compound according to claim 5 and its salts, caractêris® in that a corresponding compound of formula IIp is oxidized (see formula on the following page) ê “I 19 ^ DU-COR, ', x | OS 2 "1 (IIP) S — S 5 in which R′j and n are as defined in claim 5, and the compound obtained is recovered in free form or in the form of a salt. of formula IIpA or III 10 (CH2) n-C0-N <„2 ΠΡΑ s — s 15) ~ | ^ (CH2) n.C00-N I III II os — s in which R2 and R3 each independently of one another represent a cycloalkyl group or an alkyl group unsubstituted or substituted by a cycloalkyl, heteroaryl or aryl group and one of the symbols R2 and R3 may additionally represent the hydrogen, and their salts. *