CA1068605A

CA1068605A - Medicament based upon adenosine 5'-thiothers

Info

Publication number: CA1068605A
Application number: CA254,477A
Authority: CA
Inventors: Malka Robert-Gero; Philippe Vigier; Edgar Lederer; Constantin Bona
Original assignee: Agence National de Valorisation de la Recherche ANVAR
Current assignee: Bpifrance Financement SA
Priority date: 1975-06-09
Filing date: 1976-06-09
Publication date: 1979-12-25
Also published as: JPS52125633A; FR2313937B1; OA05351A; FR2313937A1; GB1555991A; DE2625835A1

Abstract

ABSTRACT OF THE DISCLOSURE

The invention relates to compositions having in vivo actions of inhibition of viro-induced oncogenous transformation of cells, of retardation of the cellular divisions of cells and antimitogenic properties, the active principles of which are constituted of adenosine-5'-thioethers.

They are useful for the prevention and treatment of malignant tumours and viral infections.

Description

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The invention relates to medicaments based upon adenosine `5'-thioethers having especially antiviral and antitumoral actions.
The methylation of proteins, nucleic acids and numerous metabolites is a well-known reaction, in the course of which specific enzymes, called methylases or methyl-transferases, eEfect the transference of a methyl group supplied by S-adenosyl methionine at certain precise points of the sub-stratum, especially nitrogenised bases or sugars intervening in the constitution of the nucleic acids.
It has recently been shown that tumoral tissues contain higher proportions than normal tissues of methylated nucleic -bases. In particular it has been noted that there is a relationship between the hypermethylation of the nucleic acids and the transformation of normal cells into malignant cells.
.
In correlation with this phenomenon, it has recently become known that the messenger RNA of some tumorigenous viruses, contains specific methylases.
It is known that research workers are already inter-ested in the study, especially in VitYo~ of the regulation of the methylases by natural or synthetic inhibitors. One ; known natural inhibitor is constituted by 5'-S-adenosyl-L-homocysteine 1', hereinafter designated by the abbreviation SAH, which is produced on the reaction of transference of the methyl group supplied by S-adenosyl methionine; SAH is itself a powerful inhibitor of methyl-transferases, especi-ally in vitro. These same research workers have already had the idea of effecting the synthesis of a certain number of analogues of S-adenosyl-homocysteine and of testing their inhibiting action towards methyl-transferases . .

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-: in vitro . All the synthetic inhibitors which they have described have proved much less active th~n SAH used under the same conditions, if not inactive .
The invention is based upon the dlscovery that at least certain of these analogues of SAH were on the contrary ef~ective and had a methylase-inhibitor li]ce activity in vivo with respect to methylases,more particularly the specific or non-specific methylases of the oncogenous viruses. This dis-covery was the more unexpected as SAH studied under the same conditions is substantially in~ctive or inactived, perhaps by intracellular hydrolysis or degradation.
Thus the invention concerns more particularly the application as inhibitors of the oncogenous transformation of tissues,(that is the transformation which induces the formation of tumors, -o~ viral i~fections and espPcially those caused by oncogenous viruses, of cellular divisions induced by mitogens, of substances responding to the following formula :

NH-X

N _ ~ I -:- - R - S - CH2 . N ~ N~5~ ~.
~ /
'' \l ~/ '' ~.

wherein X is hydrogen or a benzoyl group and R is a R
21r R2 . . .

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with either R1 or R2 being an atom of hydrogen, a hydrocarbon group comprising from 1 to 7 atoms of carbon, an OH, SH, CH2SH, COOH, COCH3, NH2, NHCONH3 or SCH3 group; it also being possible for R1 and R2 to form a phenyl or pyridyl ring with the CH .
group on which they are fixed; n is equal to O or 1.
A particular class of the compounds as above defined is that wherein X is hydrogen and R is a -(CH2) - CH ~ 1 group with R1 being 1 atom of hydrogen, a hydrocarbon group comprising 1 to 7 atoms of carbon, an CH, SH, CH20H, CH2SH, ~ ~ .
COOH, COCH3, NH2 or NHCONH3 group and R2 being an atom of ~
hydrogen or an OH, SH, CH20H, CH2SH, C30H, COCH3, NH2 or NHCOCH3 group; it also being possible for R1 and R2 to form a phenyl ring with the CH group on which they are fixed; n is equal to O or 1 .
: Compounds of particular interest by way of agents ~ .
inhibiting oncogenous viruses present in tumorous tissues are ; :~
those in which the radical R is an alkyl group comprising from 1 to 5 atoms of carbon, and possibly too at least one of the following functional groups : - -NH2, -SH~ - COOH
Compounds of this type which contain also a SCH3 group are also of particular interest~ .
Standard.examples of these inhibiting agents are those .
in which R is a - CH2 - CH2 - NH2 ; ~ CH2 - CH2 - SH;
- CH2 - CH - NH2 group.
COOH
. . .
Particularly interesting products are constituted by ....

` the S-isobutyl adenosine derivatives of formula :

. - . . .
~ ~
.' ~ '.
'~ .
.1 . .
:` ~'., . . . . .. .. . . .

10~136~S
-NH - X

~ CH~- C~2 _ 5 C}12 : O O

wherein isas defined aboveO
The product in which X is hydrogen (hereinafter : designated under the abbreviation SIA) is characterised by a particularly high inhibiting activity, while being of a remarkable innocuousness.
Further examples of inhibitors are-also those in which R has one of the following significances CH2 ~ CH2 - CH2 - CH3 ~CH2 CH2 - CH2 - CH2 - CH3 tCH2)6 ~ CH3 CH2 c6~
~` CH2 CH(NH2) - COOH

CH2 - CH2 - CH(NHCOCH3) - COOH ;
'! . :
, CH2 - CH20H ' ~:

CH2 - CH(OH) ~ CH20H :
m - pyridyle ; .
~, .

- : - . . , ~. . , .:

o~ :~

CH2 - CH(NH2) - COOH (isomer D) CH(CH3) - CH2 - CH

CH2 - CH(OH) - CH20H
C~12 - CH = CH2 The inhibiting activity of the said substances is evidenced by a prevention of the transformation of normal cells into mali~nant cells or, when the latter have already developed, by an interruption of their multiplication. Admitted-ly it is observed that the a~ents according to the invention can likewise induce a retardation of the multiplication of normal cells. However it is noteworthy, as evidenced by the results of the pharmacological tests which will be described ;
hereinafter, that this effect is reversible as regards the development of the normal cells, but irreversible as regards the malignant cells.
Thus these properties make the agents according to the invention acti~e principles of great value, utilisable in ;
the constitution of medicaments ~or the prevention or treat-ment of malignant tumours and viral inections .
The majority of the compounds responding to the above-indicated general formula has already been described.
It will also be recalled that several processes have been described for their preparation.
- It will be recalled, as reminder, that these products ~-can be obtained especially :
-by displacement o~ the p-toluene sulphonate group at 5' of ! ~ .

2', 3'-0-isopropylidene 5'-0-p-toluene sulphonyl adenosine~
~` with the aid of a thio-alcoholate of formula RSH, in which R has the significance indicated above, especially within dimethyl formamide or liquid ammonia (known as Baddiley's method ) ;`, ..
' .. . . . .
- . : .. : . ... .. .
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,. . . , . , .: . ' . ~ .: , :~Q16t3605 - -by direct halogenation of the C5' of adenosine ribose by thionyl chloride in hexamethyl phosphorotriamide, the obtained 5'-deoxy-5'-chloro-adenosine then being placed in contact with the corresponding thio-alcoholate RSH within an aqueous solution of sodium hydroxide (Kikugawa's method). Such methods were recalled and developed in the doctorate thesis by Michel Legraverend, maintained the 10th February 1975 at the Orsay Centre of the Paris-South University and entitled "study of the enzymatic methylation of ribonucleic acids of in v~tro transfer, inhibition of an N2 guanine methyl transferase and synthesis of new inhibitors".
Some of the compounds falling within the scope of the general formula, though not disclosed 'per se r in the prior art, are homologues of the known compounds encompassed by the general formula. For example, as illustrative of such compounds there may be mentioned the case where R is -CH2-S-CH3 ~'-S-deoxy(methylthiomethylthio)adenosin ~ which is prepared from the 5'-deoxy-5'-chloro-adenosine according to the procedure described previously and which melts at 98-99C, R is -CH(CH3)-CH2-CH3 melting at 93-95C and the N(6)-benzoyl-SIA. This latter compound can be prepared as follows:
the specific benzoylation of the nitrogen at the ~ -6 - position on the nucleus of adenosine is carried out .:
according to the method described by RANGANATHAN et al.
(J. Org. Chem, 39, (1974), 290).
10 mM of distilled benzoyl chloride are added drop-wise to a 30 ml pyridine solution containing 3 mM of SIA atOC.
The solution is stirred for 2 hours at ambient temperature and `' ' ' ,~

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thereafter 40 ml of NaOH 2 N are added to said solution.
After standing for one hour the reaction mixture is acidified at 0C by adding acetic acid thereto. The solvents are evapo-rated and the product extracted with chloroform. 1'he organic phase is scrubbed successively with a sodium bicarbonate solution, with HCl l N, with water, then dried on Mg SO~ and finally evaporated;.
A chromatographically pure compound is obtained :
Rf = 0.82 ( chloroform/methanol 8/2) MP = 210 - 21~C.
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~068~0~i Further characteristics of the invention will also appear in the course of the following description of pharmacological tests carried out with the above-defined substances. In the course of this description reference will be made to Figures 1 to 5 of the drawings, which illustrate diagrammatically the effects produced by the said substances under the conditions which will be explained later.

" lo Effect of SIA and SAH upon the growth of chicken embryo fibroblasts, respectively healthy and infected by Rous's Sarcoma virus.
~
a) Effects of SIA and SAH upon the growth of normal chicken embryo fibroblasts.
This effect was studied under the following conditions.
Embryo fibroblast cells were seeded in HAM F-10 medium (described in the article by R.G. HAM Exp. Cell. Res., 29, 515-526 (1963)), in Falcon boxes of 60 or 35 mm. diameter, at the rate of 3 x 105. The cells adhere to the bottom of the -~
box. Each time a count must be effected, the cells are detached with the aid of a 0.12% trypsin solution. The count is effected with the microscope with the aid of a haemocytometer.
The inhibitor utilised is introduced at the beginning of ;
the experiments into the medium at the desired study concen-trations. The medium is renewed on the second day and the fourth day with the inhibitors. On the fifth day the inhibitors are eliminated by repeated renewal of the medium.
The curves 1, 2 and 3 in Figure 1 respectively represent the multiplication of the cells (expressed on the ordinate axis by the number N of cells) as a function of time (expressed in days on the abscissae axis) in control cultures (curve 1), in the presence of SA~ at a concentration of 1 millimol (mM) .' ' .

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.: . , ~86Q5 (curve 2) and in the presence of SIA at a concentration of 1 mM (curve 3).
Figure 1 shows that SIA and SAH retard the growth of normal cells. However this effect is reversible, even after 5 days. The growth in fact resumes rapidly/ as soon as the inhibitor has been eliminated.
b) Inhibition of the viro-induced transformation of the cells by the 5'-thioethers of adenosine.
; System studied: chicken embryo fibroblasts infected by Rous's Sarcoma virus (RSV).
The culture medium is constituted by the HAM F-10 medium containing 5% o~ calf serum.
Chicken embryo fibroblast cells are seeded into the above-indicated medium, in Falcon boxes of 35 mm. diameter, at the rate of 106 cells per box. These cultures are infected by a :~ dilute virus suspension permitting the obtaining of 60 to 100 centres of transformed cells per box. The inhibitor is added for a duration of 48 hours, either immediately after the infection (series A), or 2 and 4 days after the infection . 20 (series B and C). After 48 hours of contact the medium is ` changed to eliminate the inhibitor and the centres formed are - counted 7 days later. During this time the medium is renewed periodically. -`~ The results appear in Table I below. In the left-hand column the inhibitors and the utilisation concentrations of these inhibitors are indicated. The numbers of centres and the inhibition percentages observed for the series A, B and C
-~ are respectively given.

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TABLE I
Effect of SIA and SAH upon the viro-induced (RSV) trans-formation of chicken embryo fibroblasts . .... ____ Number of centres ~ inhibition Control 72 SA~I 1.0 mM 58 19.5 ) SIA 0.5 mM 23 68 ) series A
SIA 1.0 mM O 100 Control 110 SAH 1.0 mM 112 O ) SIA 0.5 mM 60 45 ) series B
SIA 1.0 mM 6 95 ) Control 72 SAH 1.0 mM 60 17 ) SIA O A 5 mM 2 97 ) series C
SIA 10 mM O 100 ) The examination of this table shows that SIA is a very powerful inhibitor of the oncogenous transformation of chicken embryo fibroblasts. At a concentration of 1 mM, SIA completely ` 20 inhibits the malignant transformation, in irreversible manner.
This inhibition remains irreversible at least for 7 - 8 days.
` SAH, a natural inhibitor of transmethylases, studied for ;
comparison, hardly inhibits the transformation, probably by reason of its degradation (intracellular hydrolysis). The -following table shows the results obtained with analogues of SIA.
In the following Table II there appear the results obtained with analogues responding to the general formula indicated above. They are identified in the table by the significance of their R group. Moreover this table indicates:-the concentration of each inhibitor utilised, the duration of contact of the inhibitor with the culture, the percentage of inhibition of the oncogenous transformation : of the chicken embryo fibroblast.

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TABLE II
Activities of various analogues upon the chicken embryo fibroblasts infected by Rous's virus Group R of Conc. ~ime of ~O lnhlbition the analogue contact of the trans-formatlon -CH3 0.5 mM 24 hours 70 ,. 0.5 mM 48 " 95 -(CH2)2 - CH3 0.5 mM 24 " 44 ll 0.5 mM 48 " 83 -(CH2)3 - CH3 0.5 mM 24 " 62 0.5 mM 48 " 86 CH2 - CH - NH2 1. mM 48 " 87 CH2 - CH2 SH 0.5 mM 24, " 26 0.5 mM 48 " 84 1. mM 48 " 96 COOH
-CH2 - CH - NH2 1. mM 48 " 76 -CH2 - CH - COOH 1. mM 48 " 58 . :
-(CH2)6-CH3 0.1 mM 48 " 33 -CH2 ~ C H 0.1 mM 48 " 36 ~ .

1. mM 48 " 98 0.5 mM 48 " 93 -CH2 - S - CH 0-5 mM 48 " 100 0.25 mM 48 " 95 -cH2-cH(NH2)-cooH 0.5 mM 48 " 70 ~: ;
(D-isomer) .
( 3) C2H5 0.5 mM 48 " 99 -CH2-CH(OH)-CH2OH 0.5 mM 48 " 70 ;~
-CH2-CH=CH 0.5 mM 24 " 99 -cH2-cH-(cH ) 0.5 mM immediate 99 . _ . .. __ ' ' .'. . " ' :: :
, . ' ~ ,"'`""-:;'.

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X is hydrogen except the last one (~) (in all the compounds listed in table II in which X is a benzoyl group).
This latter table shows the fact that all the tested substances exert a significant inhibiting action upon the oncogenous transformation of chicken embryo fibroblasts.

2. Effect of S-isobutyl - adenosine upon the oncogenous transformation of mouse cells by the Sarcoma Murin virus (M-MuSV) . .
The experiments were e~ected ~pon mo~se ~ibroblast cells (~Lg cells) seeded the previous evenin~ upon H~ medium in Petri boxes (5.104 cells/35 mm. Petri box); these cells `~
are placed in contact for 2 hours with the M-MUSV virus, then returned into HAM medium containing or not containing the substance to be tested, in the present case SIA. The cells remain in contact with the inhibitor for 24 or 48 hours. The : : ~' inhibitor is eliminated by changing of the medium, and the centres formed are counted 3 days after the eli~ination of the inhibitor. The results are indicated in the following Table ~-III, in which there appear the doses of inhibitor utilised, the contact time and the number of transformed centres.

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TABLE I I I
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. .... __ __ SIA Contact time Number of centres transformed ._ ....... _.__ 0 24 hours Confluent centres 2 mM ,~ 148 _ ':
,~ 0 48 hours Confluent centres 0.5 mM ,l 218 mM __ 18 :~

One notes the proliferation of the malignant cells in the control culture, whereas SIA very efficaciously inhibits the malignant transformation of the mouse cells by the Sarcoma Murin virus.

3. Influence of SIA upon intracellular macromolecular synthesis.
.. .. _ _ ; The foregoing test have permitted of demonstrating the fact that SIA had the effect of arresting cellular division, this effect being both particularly vigorous and irreversible in relation to cells having suffered an oncogenous transformation. This effect can likewise be .. ~ ~ . .
demonstrated by the study of the action of the inhibitor ~ -upon macromolecular synthesis. This action was demon-strated upon cultures of normal cells and transformed '''' .

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. cells under the conditions set forth under 1.) above, on the occasion of the study of the effect of adenosine 5'-thioethers upon the growth of chicken embryo fibroblasts, by isotopic !. marking of these cultures, by incorporation of [3H] leucine, of ;:
[3H] thymidine and of [3H~ uridine respectively i.n normal and tran.sformed cells of different cultures, of control cells on the one hand and of cells cultivated in the presence of SIA, for ~ ~ .
durations respectively of 24 and 48 hours, on the other.
The results of these tests are the subject of the graphic representation in Figure 2, which shows the percentages of incorporation in the cells of the different cultures~
of [3H] leucine (results grouped under bracket A), of [3H] thymidine (results grouped under bracket B), : of [3H~ uridine (results grouped under bracket C).
The results grouped under the brackets n concern normal cell cultures, those grouped under bracket t cultures of transfo.rmed cell.
The vertical elongated zones in solid lines (the length of which is proportional to the percentage of incorporation of the .
marker) designated by the reference numerals 1 concern the control .
.......... cultures, without inhibitor; the solid line zones designated by the .
reference numerals 2 concern the percentages of incorporation of the marker in the cultivated cells, maintained in the presence of 1 mM of SIA for 24 hours, and the zones 3 are representative of the percentages of incorporation of the marker in the cultivated . cells, maintained in the presence of lmM of SIA for 48 hours. .
.. The dotted line zones are representative of the percentages of incorporation of the marker when the latter has been introducedinto the cultures 24 hours after the elimination of the inhibitor, at the concentration and after the contact durations which were indicated above.
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. .

. - 14 -6~6~i Figure 2 shows clearly that in the normal cells the incorpo-rations of [3H] leucine, [3H] thymidine and [3H~ uridine are inhibited substantially in the same manner in the presence of SIA. However this effect is reversible. In fact a resumption of the macromolecular syntheses is noted as soon as the inhibitor is eliminated.
In the presence of the inhibitor, it is noted that the same doses of SIA exercise a greater effect of inhibition of the development of the transformed cells than that of the normal cells, and above all that the maintenance of the inhibitor in contact with the transformed cells for a sufficient time, especially for 48 hours, involves an irreversible inhibition of all the incorporations in the transformed cells, that is the arresting of the macromolecular syntheses (especially of the proteins, of the deoxyribonucleic acids and of the ribonucleic - acids, to which there correspond respectively the three markers utilised, namely [3H] leucine, [3H] thymidine and [3H] uridine) and consequently arresting of the cellular division.

; ~. Demonstration of the antimitogenic properties of adenosine 5'-thioethers.
The description of the following tests aims to demonstrate the antimitogenic properties of adenosine 5'-thioethers, of which SIA is representative. The antimitogenic effect of the tested substance results from the capacity which it possesses for inhibiting the mitogenic action of substances known as having this effect in relation to lymphocyte cultures. The results obtained in relation to mouse spleen lymphocytes, rabbit spleen lymphocytes and human lymphocytes are the subject of the graphic representations in ~igures 3, 4 and 5 respectively.

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` The lymphocyte cultures were effected in accordance with the technique described in the article by C. Bona et Coll.
published in "The ~ournal of Immunology, vol. 112, No.6, June 1974, 2028" and in the presence of the mitogenic agents identified below and of the substance to be tested, in the present case SIA, at two different concentrations : 0.1 and 0.3 mM, for 48 hours as regards the mouse spleen lymphocytes (Fig. 3), 72 hours as regards ; the rabbit spleen lymphocytes (Fig. 4) and 120 hours as regards the human lymphocytes (Fig. 5). In each case cultures of these same lymphocytes are effected in the presence of the mitogenic agents alone (control cultures). The mitogenic or antimitogenic effect according to cases of the mitogenic agents and of the SIA
is set forth by the radioactivity of the lymphocytes resulting from the incorporation of tritiated thymidine therein.
The utilised mitogenic agents are the following:-Con A : Concavaline A : T mitogenic in mouse and rabbit, T and B
~ in man.
;I PHA : Phytohaemagglutinine : T mitogenic in mouse and rabbit, T and B in man.
ALS : Antilymphocytary serum : T mitogenic in man.
PPD : Tuberculin : specific mitogenic of T cells in the case where the subject has previously been sensitised by mycobacteria.
NWSM : Hydrosoluble mitogenic agent extracted from Nocardia cells:
mitogenic of B cells in mouse and rabbit.
Anti-B4 : Serum directed against the genetic determinants of the light immunoglobuline chain of rabbit, carried by the : B cells of rabbit: thus it is a B mitogenic of rabbit.
` PG : Peptidoglycan of E.coli : B mitogenic for mouse and rabbit.
LPS : Lipopolysaccharide of Salmonella enteridis :
B mitogenic for the mouse.
Lip. A : Lipid A or mitogenic principle of LPS.

: ~' 0~l~36~5 The doses expressed in microgrammes (~), or in dilutions as regards ALS or Anti-B4 serum, of the antimitogenic agents used in each of the described tests are indicated in the following table, respectively, in connection with the cultures of mouse spleen lymphocytes, rabbit spleen lymphocytes and human lymphocytes:

Mouse Rabbit Human spleen spleen lymphocytes lymphocytes lymphocytes Con A 3 ~ 5 ~ 5 ~
PHA 0~2 ~ 1 ~ 1 y PPD - - 10 r ~
NWSM 10 ~ 50 ~ 100 Anti-B4 - 1/50 PG 50 ~ 100 ~ - -; LPS 10 ~ - -Lip. A 10 ~
The results are grouped in Figs. 3 to 5 for each selected mitogenic agent. The lengths of the elongated zones are pro-` portional to the measured radioactivity R (strokes per minute multiplied by 10 3). The zone simply defined by a solid line corresponds to the results obtained in the presence of the -mitogenic agent alone, the zone hatched with diagonal lines to - the results obtained in the presence of the mitogenic agent and SIA at a concentration of 0.1 mM and the zone hatched with horizontal lines to the results obtained in the presence of the mitogenic agent and SIA at a concentration of 0.3 mM.
The continuous horizontal line represented in each Figure corresponds to the incorporation of the marker in control cultures, in the absence both of the mitogenic agent and of SIA.
The incorporated radioactivities measured for cultures of lymphocytes in the presence of SIA alone have also been represented. The ' ` -36~)5 '.~ '::, corresponding results are indicated above the abbreviation SIAwhich is to be found in each of Figs. 3 to 5.
The drawings show the remarkable antimitogenic properties of SIA. A notable inhibition is observed of the mitogenic action of the selected mitogenic agents, in most cases for an SIA
concentration of 0.1 mM. In all cases it is very great at a concentration of 0.3 mM, from which it results that adenosine 5'-thioethers not only inhibit cellular division, but likewise counteract effectively the action of mitogenic agents.
5. Toxicity tests a) Acute toxicity.
Three batches of five mice, weighing 20 to 25 g., were the object of these tests. SIA in suspension in physiological serum was administered to them in one single intraperitoneal injection.
The doses administered to the mice of the first batch were lO0 mg.
per kilo, to those of the second batch 200 mg. per kilo and to those of the third batch 500 mg. per kilo.
The mice were examined after 1 hour, 2 hours and 24 hours.
Mortality was zero, even after several weeks.
::
b) Chronic toxicity.
These tests were effected upon five control mice and fifteen treated mice. -The controls received physiological serum intraperitoneally, at the rate of l ml. per lO g. of weight. The other mice received .. .
l ml. of a suspension containing l mg. of SIA (in physiological ~
. .
serum). The injections were effected in the rhythm of 30 injections in two months.
After the 28th injection, one single dead mouse is found, ~
probably rather by reason of the trauma caused by the injection ' than by the content of the injected suspension.

.
~L~6~il6~5 Thus, these results display a remarkable innocuous-ness of SIA in mice.
The adenosine 5'-thioethers constitute active prin-ciples of value for the constitution of medicaments utilisable for the prevention or treatment of malignant tumours and viral infections. Their major antimitogenic properties also make them valuable active principles for the constitution of me-dicaments for the treatment or prevention of leukaemias and myelomas.
The invention is thus concerned with pharmaceutical compositions containing the compounds as defined hereabove, particularly an effective dose thereof, in association with a pharmaceutically or physiologically acceptable vehicle.
Particularly the invention is concerned with compo-sitions in which the active compounds are associated with solid or liquid physiologically acceptable carriers suitable for oral administration, or in which they are associated with carriers suitable for their administration by the rectal route.
~ According to a preferred embodiment of the invention, said compositions are administrated by the parenteral route.
The invention is concerned in particular with liquid composi-tions containing at least one of the compounds as above defi-ned associated with an injectable, sterile liquid vehicle~ -As is self-evident and as moreover already appears from the foregoing, the invention is in no way limited to those of its manners of application and realisation which have been more especially envisaged; on the contrary it includes all variants thereof .

- 19 _

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows :

1 Composition having in vivo actions of inhibition of the viro-induced oncogenous transformation of cells, of retardation of the cellular division in relation to cells having suffered an oncogenous transformation, and antimitoge-nic properties,wherein its active principle, which is asso-ciated with a pharmaceutical carrier, is constituted by at least one substance of formula :

wherein X is hydrogen or a benzoyl group and R is a with either R1 or R2 being an atom of hydrogen, a hydrocarbon group comprising from 1 to 7 atoms of carbon, an OH, SH, CH20H, CH2SH, COOH,COCH3, NH2, NHCONH3 or SCH3 group; it also being possible for R1 and R2 to form a phenyl or pyridyl ring with the CH group on which they are fixed; n is equal to 0 or 1.

2 - Composition according to claim 1 wherein X is hydrogen and R is a - (CH2)n-C?-R1 - R2 group, with R1 being an atom of hydrogen, a hydrocarbon group comprising 1 to 7 atoms of carbon, an OH, SH, CH20H, CH2SH, COOH, COCH3, NH2 or NHCONH3 group and R2 being an atom of hydrogen or an OH, SH, CH20H, CH2SH, COOH, COCH3, NH2 or NHCOCH3 group; it also being possible for R1 and R2 to form a phenyl ring, with the CH group on which they are fixed; n is equal to 0 or to 1.

3 - Composition according to Claim 1 or 2, wherein in the said formula the radical R is an alkyl group comprising from 1 to 5 atoms of carbon, containing possibly too at least one of the following functional groups : - NH2, - SH,-COOH .

4 - Composition according to claim 1 or 2 wherein in the said formula R is an alkyl group comprising from 1 to 5 atoms of carbon and a - SCH3 group.

5 - Composition according to claim 1 or 2 wherein in the said formula the radical R is a -CH2 - CH2 - NH2; - CH2 - CH2 -SH ; - CH2- - NH2 group .

6 - Composition according to Claim 1, wherein its active principle is constituted by S-isobutyl adenosine .

7 - Composition according to Claim 1 or 2 wherein in the said formula the radical R has one of the following signifi-cances : -(CH2)6 - CH3 CH2 - CH(NH2) - COOH

CH2 - CH2-CH(NHCOCH3) - COOH

CH2 - CH(OH) - CH20H.

8. Composition according to Claim 1, characterized in that the vehicle is injectable.