FR2626002A1 - DIDEOXYDIDEHYDROCARBOCYCLIC NUCLEOSIDES AND PHARMACEUTICAL COMPOSITION CONTAINING SAME - Google Patents

Abstract

The invention relates to novel compounds of formula (CF DRAWING IN BOPI) wherein X represents H, NRR ** 1, SR, OR or a halogen; Z represents H, OR ** 2 or NRR ** 1; R, R ** 1, R ** 2 represent H, a C1 to C4 alkyl group or aryl, and their pharmaceutically acceptable derivatives. It also relates to pharmaceutical formulations containing in particular compounds of the above formula. The compounds of the invention are endowed with antiviral and antitumor activity.

Description

The present invention relates to nucleoside analogs

  didéoxydidéhydrocarbocycliques. It relates more particularly to analogues of the type of

  carbocyclic nucleosides of 2 ', 3'-dideoxy-2', 3'-didehyde

  dropurine and their use in therapeutics, in particular

as antiviral agents.

  Because of the similarity between the viral functions and the functions of the host cells, it is difficult to selectively attack a virus while leaving the host cells intact. There are therefore relatively few effective agents against viruses themselves, and it is difficult to find antiviral agents with a suitable therapeutic index, that is, agents that produce a significant antiviral effect at a dose level. for which the agent has a

  acceptable profile of toxicity or side effects.

  A group of viruses that have recently become of major importance includes retroviruses responsible for acquired immune deficiency syndrome (AIDS) in humans. These viruses have already been designated according to various terminologies, but they now respond to the general name of human immunodeficiency virus (HIV); two of these viruses, HIV-I and HIV-II, have been reproducibly isolated from AIDS patients and related disease states such as the bound complex

  AIDS (ARC) and persistent generalized lymphadenopathy

  aunt. Although a number of nucleosides have been taught as useful substances in the treatment of conditions related to HIV infections, only zidovudine (AZT, Retrovir) has received regulatory approval for the treatment of such conditions. However, it is known that zidovudine produces serious side effects, resulting in the suppression of bone marrow;

  which leads to a decrease in the number of leukocytes accom-

  with marked anemia, and it is necessary to

  find effective agents that are less cytotoxic.

  The Applicant has just found a new class of analogues of the nucleoside type endowed with antiviral activity. Accordingly, the invention provides in a first aspect a compound of formula (I) X * N I u. (Uj

Z N

  Wherein X is hydrogen, NRR1, SR, OR or halogen; Z is hydrogen, OR2 or NRR1; R, R1 and R2 may be the same or different and are selected from hydrogen, C1-C4 alkyl groups and aryl groups; and pharmaceutically acceptable derivatives thereof. Those skilled in the art will recognize that

2626002 '

  compounds of formula (I) are cis compounds and furthermore that the cyclopentene ring of the compounds of formula (I) contains two centers of chirality (designated in formula (I) by the sign *) and that they may therefore exist as two optical isomers (i.e., enantiomers) and as mixtures thereof, including racemic mixtures. All these isomers and mixtures thereof, including racemic mixtures, are within the scope of the invention. Thus, in the compounds of formula (I), the chiral center to which the base is attached to the R configuration and the chiral center to which the CH 2 OH group is attached to the S configuration (isomer D below) or the center of chirality to which the base is attached to the S configuration and the center of chirality to which the CH 2 OH group is attached to the R configuration (isomer L hereinafter). The compounds are advantageously in the form of a racemic mixture or mainly in the form of the pure D-isomer. The D isomers can be represented by the formula (Ia) X NN

NOT//\ \

I (a)

Z N N

  wherein X and Z are as defined for formula (I). The references that are made below to compounds

  of formula (I) include compounds of formula (Ia).

  Those skilled in the art will also appreciate the fact that some of the compounds of formula (I) can exist in several tautomeric forms and that all these

  tautomers fall within the scope of the invention.

  The term halogen used herein refers to fluorine, chlorine, bromine and iodine; when X is a halogen, it is preferably chlorine. The term C1-C4 alkyl used herein refers to a straight chain or branched chain alkyl group, for example methyl, ethyl,

  n-propyl, isopropyl, n-butyl, sec-butyl and tertiary

  butyl. The C1-C4 alkyl group is advantageously a

methyl group.

  The term aryl used herein refers to any monocyclic or polycyclic aromatic group and includes unsubstituted and substituted aryl groups (such as phenyl, tolyl, xylyl, anisyl) and unsubstituted and substituted aralkyl groups including aryl groups. (C1-C4) alkyl such as

  phen- (C1-C4) alkyl, for example benzyl or phenethyl-

  the. In the compounds of formula (I), Z is from

preferably an amino group.

  In a preferred first class of compounds

  of formula (I), X is a group OR, in particular an OH group.

  In another preferred class of compounds of formula (I), X is NRR1, especially NH2, or a

hydrogen atom.

  Particularly preferred compounds of formula (I) are those wherein Z is NH 2 and X is H, NH 2 or especially OH. Those are

  especially those compounds which have therapeutic indices

  particularly valuable as antiviral agents. The term "pharmaceutically acceptable derivative" means any pharmaceutically acceptable salt, ester or salt of such a ester of a compound of formula (I) or any other compound which, by way of

  administration to the patient, is able to

  or indirectly) a compound of formula (I) or a metabolite or a residue endowed with antiviral activity of this compound. Preferred esters of the compounds of formula (I) include carboxylic acid esters wherein the non-carbon portion of the ester group is selected from hydrogen, straight-chain or branched chain alkyl groups (eg, methyl, ethyl, n-propyl, t-butyl, n-butyl), alkoxyalkyl (e.g. methoxymethyl), aralkyl (e.g. benzyl), aryloxyalkyl (e.g. phenoxymethyl), aryl (e.g. phenyl optionally substituted by halogen, alkyl C1 to C4 or C1 to C4 alkoxy); sulfonic esters such as alkyl or aralkylsulfonyl (for example methanesulfonyl); amino acid esters (by

  L-valyl or L-isoleucyl) and monophosphate esters.

  phoric, diphosphoric or triphosphoric.

  As regards the esters defined below,

  above, unless otherwise specified, any alkyl group present preferably contains 1 to 18 carbon atoms, especially 1 to 4 carbon atoms. Any aryl group present in such esters advantageously comprises

a phenyl group.

  Pharmaceutically acceptable salts of the compounds of formula (I) include those derived from

  inorganic and organic acids and bases

  Maceutically acceptable. Examples of acids

  include hydrochloric acid, hydrobromic acid,

  sulfuric, nitric, perchloric, fumaric, maleic, phosphoric, glycolic, lactic, salicylic, succinic, toluene-psulfonic, tartaric, acetic,

  citric, methanesulfonic, formic, benzoic, malonic

  that, naphthalene-2-sulfonic and benzenesulfonic. other

  acids such as oxalic acid, although not

  are acceptable in themselves, may be useful in the preparation of salts which may be used as intermediate compounds for obtaining the compounds of the invention and their pharmaceutically acid addition salts thereof

acceptable.

  Salts derived from appropriate bases include

  salts of alkali metals, for example sodium, alkaline earth metals (for example magnesium), ammonium

  and NR4 + (where R is C1-C4 alkyl).

  When referring hereinafter to a compound according to the invention, this reference comprises both

  the compounds of formula (I) and their pharmaceutical derivatives

acceptable.

  Representative compounds of formula (I) include the following:

  (La, 4a) -4- (6-chloro-9H-purin-9-yl) -2-cyclopentyl

ténylcarbinol;

  (La, 4a) -4- (6-hydroxy-9H-purin-9-yl) -2-

cyclopenténylcarbinol;

  (La, 4a) -4- (6-Amino-9H-purin-9-yl) -2-cyclopentyl

ténylcarbinol;

  (La, 4a) -4- (6-mercapto-9H-purin-9-yl) -2-

cyclopentenylcarbinol;

  (La, 4a) -4- (2-amino-6-chloro-9H-purin-9-yl) -2-

cyclopenténylcarbinol;

  (La, 4a) -4- (2-amino-6-hydroxy-9H-purin-9-yl) -2-

cyclopenténylcarbinol;

  (La, 4a) -4- (2,6-diamino-9H-purin-9-yl) -2-

  cyclopenténylcarbinol; in the form of a racemic mixture or a

individual enantiomer.

  The compounds of the invention themselves possess antiviral activity and / or can be metabolized to such compounds. In particular, these compounds are effective for inhibiting retrovirus replication, including human retroviruses such as human immunodeficiency virus (HIV), which is responsible for AIDS. Other compounds of the invention possess anticancer activity, especially those in which X is hydrogen. According to another aspect of the invention, there is therefore provided a compound of formula (I) or a pharmaceutically acceptable derivative thereof, intended to be used as an active therapeutic agent, in particular as an antiviral agent, for example in the treatment

  of retrovirus infections, or as an anticancer agent.

  In another aspect, or alternatively, there is provided a method of treating a viral infection, particularly an infection caused by a retrovirus such as HIV, in a mammal including humans, which comprises administering a effective amount of an antiviral compound of formula (I) or a pharmaceutically acceptable derivative

-20 of such a compound.

  It is also proposed according to another aspect or alternatively the use of a compound of formula (I) or a pharmaceutically acceptable derivative thereof for the preparation of a medicament for the treatment of a viral infection or its use as an anticancer agent. Compounds of the invention endowed with antiviral activity are also useful in the treatment of AIDS-related conditions such as AIDS-related complex (ARC), progressive generalized lymphadenopathy (PGL), neurological conditions associated with AIDS (such as such as dementia or tropical paraparesis), HIV-positive and HIV-positive status, Kaposi's sarcoma, and

thrombocytopenic purpura.

  The antiviral compounds of the invention are also useful in preventing the progression of clinical disease of subjects who are HIV antibody or HIV antigen positive and in prophylaxis.

  following an exposure to HIV viruses.

  The antiviral compounds of formula (I) or their pharmaceutically acceptable derivatives can also be used in the prevention of viral contamination of physiological fluids such as blood or sperm in vitro. Some of the compounds of formula (I) are also useful as intermediates in the preparation

other compounds of the invention.

  The person skilled in the art is able to understand that

  reference to a treat-

  This covers both prophylaxis and treatment.

  curative of infections or established symptoms.

  It should be further noted that the amount of a compound of the invention that is to be used in a treatment varies not only depending on the particular compound chosen, but also with the route of administration, the nature of the condition being treated and the age and condition of the patient, and that it is ultimately

  the discretion of the attending physician or veterinarian.

  In general, however, a suitable dose is in the range of about 1 to about 750 mg / kg, for example, a range of about 10 to about 750 mg / kg of body weight, such as a range of 3 to approximately 120 mg per kilogram of patient body weight per day, preferably in

  the range of 6 to 90 mg / kg / day, particularly in the

range from 15 to 60 mg / kg / day.

  The desired dose can advantageously be

  presented in a single dose or in divided doses

  ministries at appropriate intervals, for example two,

  three, four, or more than four dose fractions per day.

  The compound is advantageously administered in unit dosage form, for example containing 10 to 1500 mg, more preferably 20 to 1000 mg, especially 50 to 700 mg.

  of active ingredient per unit dosage form.

  Ideally, the active ingredient should be administered so as to achieve peak concentrations of the active compound in the plasma of about 1 to about 75 gM, more preferably about 2 to 50 am, especially about

  about 30 gM. This can be achieved, for example, by injecting

  intravenous solution of a 0.1-5% solution of the active ingredient, optionally in a physiological saline solution, or by oral administration in the form of a bolus containing about 1 to about 100 mg / kg of active ingredient. Suitable blood levels may be maintained by continuous infusion to provide about 0.01 to about 5.0 mg / kg / hour or by intermittent infusions providing about 0.4 to about 15 mg / kg

of active ingredient.

  Although it is possible for a compound of the invention, for therapeutic use, to be administered as a crude chemical, it is preferred that the active ingredient be presented as

pharmaceutical formulation.

  The invention thus further proposes a formulate

  pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable derivative thereof

  together with one or more pharmaceutical

  acceptable and, optionally, other

  therapeutic and / or prophylactic agents. The carrier (s) must be "acceptable" in that they must be compatible with the other ingredients of the

  wording and must not harm the recipient.

  Pharmaceutical formulations include formulations that are suitable for oral, rectal, nasal, topical (including oral and sublingual), vaginal or parenteral (intramuscular and intravenous) administration or in a form suitable for administration by inhalation or insufflation. . In

  appropriate cases, the formulations can be conveniently

  They are presented in physically separate dosage units and can be prepared by any of the methods well known in the field of pharmacy. All processes involve the step of bringing the active compound into association with liquid vehicles or finely divided solid carriers or both and then, if necessary,

  forming the product into the desired formulation.

  Pharmaceutical formulations that are suitable

  for oral administration can advantageously be presented. in physically distinct units such as capsules, cachets or tablets each containing a predetermined amount of the active ingredient; in the form of a powder or granules; in the form of a solution, a suspension, or in the form of an emulsion. The active ingredient can also be presented in the form of a bowl, an electuary or a paste. Tablets and capsules for oral administration may contain conventional excipients such as binders, fillers, lubricants, disintegrating agents or wetting agents. The tablets may be coated according to methods well known in the art. Oral liquid preparations may be, for example, in the form of suspensions, solutions, emulsions in water or in oil, syrups or elixirs, or they may be presented in the form of a dry product to be mixed with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, emulsifiers, non-aqueous vehicles (which may include

  edible) or preservatives.

  The compounds according to the invention may also be formulated for parenteral administration (for example by injection, in the form of a bolus or by continuous infusion) and they may be presented under one embodiment.

  unit dosage form in ampoules, in syringes prior to

  loaded or in multi-dose containers with the addition of a preservative. The compositions may affect such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulating agents such as suspending agents, stabilizing agents and / or dispersing agents. Alternatively, the active ingredient may be in powder form, obtained by aseptic isolation of sterile solid material or lyophilization from solution, of powder to be mixed with a suitable vehicle,

  sterile pyrogen-free water, for example, before use.

  tion. For topical administration to the epidermis, the compounds according to the invention may be formulated as ointments, creams or lotions, or as a transdermal adhesive dressing. Ointments and creams may, for example, be formulated with an aqueous or oily base supplemented with suitable thickening and / or gelling agents. Lotions can be formulated with an aqueous or oily base and they also generally contain one or more emulsifiers, stabilizing agents, dispersing agents, suspending agents, agents and the like.

thickeners or coloring agents.

  Formulations suitable for topical administration in the mouth include tablets containing the active ingredient in a flavored base, usually sucrose and gum

  arabic or gum tragacanth; tablets

  taking the active ingredient in an inert base such as gelatin and glycerine or sucrose and gum arabic; and mouthwash compositions comprising the active ingredient in a suitable liquid vehicle.

  Pharmaceutical formulations that are suitable

  For a rectal administration whose support is a solid material, they are very advantageously presented as suppositories containing a unit dose. Suitable carriers include cocoa butter and other materials commonly used in the practice, and the suppositories may conveniently be formed by adding the active compound to one or more carriers.

  softened or melted, the operation being followed by a cooling

  deformation and forming in molds.

  Formulations suitable for vaginal administration may be presented as pessaries, buffers, creams, gels, pastes, foams or

  sprayable compositions containing, in addition to the

  active ingredient, suitable supports known in the art. For intranasal administration, the compounds of the invention can be used as a sprayable liquid composition or in the form of drops. Drops may be formulated with an aqueous or non-aqueous base also comprising one or more dispersing agents, solubilizing agents or suspending agents. Sprayable liquid compositions are

  conveniently delivered using pressure vessels.

  For administration by inhalation, the compounds according to the invention are conveniently delivered by an insufflator, nebulizer or pressure vessel or by other convenient means for delivering an aerosolized spray. Pressurized containers may contain a suitable propellant such as dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol, the metered unit can be determined using a

  valve intended to deliver a measured quantity.

  Alternatively, for administration by inhalation or insufflation, the compounds according to the invention may take the form of a dry powder composition, for example a powder mixture of the compound and a suitable powder base. such as lactose or starch. The powder composition may be presented in a unit dosage form, for example in capsules or cartridges or for example in gelatin envelopes or in the form of blisters, from which the powder may

  be administered with the aid of an inhaler or an insuffer-

flattering.

  When desired, the formulations described above may be used in a form adapted to allow sustained release of the active ingredient. The pharmaceutical compositions according to the invention may also contain other active ingredients such as antimicrobial agents or preservatives. The compounds of the invention may also be

  used in combination with other therapeutic agents

  such as other anti-infective agents. In particular, the compounds of the invention can be

  used together with known antiviral agents.

  According to another of its aspects, the invention thus proposes an association formed of a compound of formula (I) or of a physiologically acceptable derivative of this compound with another agent endowed with therapeutic activity,

in particular an antiviral agent.

  The combinations to which reference is made above can advantageously be presented for use in the form of a pharmaceutical formulation and, consequently, pharmaceutical formulations comprising an association such as

  defined above together with a phar-

  Maceutically acceptable is another aspect of the invention. Beneficial therapeutic agents & use

  in these associations include acyclic nucleosides

  such as aciclovir, interferons such as

  interferon, renal excretion inhibitors such as probenicid, nucleoside transport inhibitors such as dipyridamole, 2 ', 3'-dideoxynucleosides such as 2', 3'-dideoxycytidine, 2 ', 3'-dideoxyadenosine , 2 ', 3'-dideoxyinosine, 2', 3'-dideoxythymidine and the

  2 ', 3'-dideoxy-2', 3'-didehydrothymidine and immunomodula-

  such as interleukin II (IL2) and the factor

  stimulating colonies of granulocyte macrophages (GM-

  CSF), erythropoietin and ampligen.

  The individual components of these associations may be administered successively or simultaneously in

  separate or combined pharmaceutical formulations.

  When the compound of formula (I) or a pharmaceutically acceptable derivative thereof is used in combination with a second therapeutic agent active against the same virus, the dose of each compound may be different from that used when using the

  compound alone. Appropriate doses are easily

specified by those skilled in the art.

  The compounds of formula (I) and their pharmaceutically acceptable derivatives can be prepared by any method known in the field of the preparation of

compounds of similar structure.

  Processes suitable for preparing the compounds of formula (I) and their pharmaceutically acceptable derivatives are described below; groups X and Z are as defined above, unless otherwise specified. It should be noted that the following reactions may require the use of starting materials, or may be conveniently applied to starting materials which carry protected functional groups, and removal of the protecting groups may therefore be necessary as an intermediate step. or final step for obtaining the desired compound. The protection and elimination of the protection of functional groups can be carried out by conventional means. Thus, for example, amino groups may be protected by a group selected from aralkyl (e.g. benzyl), acyl or aryl (e.g., 2,4-dinitrophenyl) moieties; the subsequent removal of the protecting group being carried out at the appropriate time by hydrolysis or hydrogenolysis, as appropriate, under normal conditions. Hydroxyl groups may be protected by the use of any conventional hydroxyl protecting group, as described for example in "Protective Groups in Organic Chemistry", edited by JFW McOmie (Plenum Press, 1973) or "Protective Groups in Organic Synthesis "by Theodora W. Greene (John Wiley and Sons, 1981). Examples of groups suitable for the protection of hydroxyl groups include groups selected from alkyl radicals (for example methyl, tert-butyl or methoxymethyl),

  aralkyl (for example benzyl, diphenylmethyl or triphenyl)

  nylmethyl), heterocyclic groups such as tetrahy-

  dropyranyls, acyl groups (eg acetyl or benzoyl) and silyl groups such as

  trialkylsilyl (for example tert-butyldimethylsilyl).

  Groups protecting hydroxyl functions can be removed by conventional techniques. Thus, for example, alkyl, silyl, acyl and heterocyclic groups can be removed by solvolysis, for example by hydrolysis under acidic or basic conditions. Aralkyl groups such as triphenylmethyl can likewise be removed by solvolysis for example by hydrolysis under acidic conditions. Aralkyl groups such as benzyl may be cleaved by hydrogen blotting in the presence of a noble metal catalyst such as palladium on charcoal. Silyl groups can also be conveniently removed using a source

  fluoride ions such as tetra-n-butylammonide fluoride

monium.

  In a first process (A), compounds of formula (I) and their pharmaceutically acceptable derivatives can be prepared by reaction of a compound of formula (II) X

// \ / NH2

NOT

I / \\ / \ 2

I

Z N NH

(II) -

HO-CH2 \ /. II

  ! I (wherein X and Z are substituents having the definition given for formula (I) or are protected forms thereof and the hydroxyl group in the cyclopentenylcarbinol group may be in a protected form) or a pharmaceutically acceptable derivative thereof composed with a reagent selected from formic acid and its reactive derivatives, the reaction being followed, when necessary, by the removal of unwanted groups introduced by said reagent and / or the elimination of all

protective groups present.

  Examples of suitable formic acid derivatives which can be used in process (A) above include orthoformates (e.g.

  triethylorthoformate), dialkoxymethyl acetates

  (for example diethoxymethyl acetate), dithioformic acid, formamide, s-triazine or formamidine acetate. Unwanted groups introduced by formic acid or a reactive derivative of this acid can advantageously be removed by gentle hydrolysis, for example by using an inorganic acid such as the acid

aqueous hydrochloric acid.

  When a trialkyl orthoformate such as triethyl orthoformate is used, it is also advantageously the solvent for the reaction. Other solvents which can be used include amides (for example dimethylformamide or dimethylacetamide), chlorinated hydrocarbons (for example dichloromethane), ethers (for example tetrahydrofuran) or nitriles (for example

example acetonitrile).

  In some cases (eg when

  uses a trialkyl orthoformate such as orthoformate

  triethylmethylate), the reaction can advantageously be carried out in the presence of a catalyst such as a strong acid (for example concentrated hydrochloric acid, nitric acid or sulfuric acid). The reaction can be carried out at a temperature in the range of -25 to +150 ° C, for example from 0 to 100 ° C and advantageously

at room temperature.

  In another process (B), compounds of formula (I) and their pharmaceutically acceptable derivatives or a protected form of these compounds are exposed to an interconversion reaction in which the initially present substituent X is replaced by a different substituent X and / or the Z group initially present is replaced by a different Z group, the operation being followed, if necessary, by the elimination of all groups

protectors present.

  In one embodiment of the process (B), compounds of formula (1) in which X represents a group RR1 (where R and R1 are as defined above)

  can be prepared by amination of a corresponding compound

  compound of formula (I) wherein X represents a halogen atom (for example chlorine). The amination can be carried out by reaction with a reagent HNRR1 (where R and R1 are as defined above), advantageously in a solvent such as an alcohol (for example methanol). The reaction can be carried out at any suitable temperature and preferably at a high temperature, for example at reflux or, when using liquid ammonia, in a sealed tube at a temperature of about 50 ° C.

  at 80 ° C. Suitable conditions for the transformation of

  Halides in secondary and tertiary amines have also been described by I.T. Harrison et al.

  Compendium of Organic Synthetic Methods, Wiley-Inter-

  Science, New York (1971), pp. 250-252.

  In another embodiment of process (B), compounds of formula (I) in which X represents a group OR (where R is as defined above) can be prepared by displacement of the atom of halogen (eg chlorine) with a suitable RO- anion. When R represents a hydrogen atom, the displacement reaction can be carried out by hydrolysis which can be carried out in water or in a mixture of water and a water-miscible solvent such as alcohol (for example methanol or ethanol), an ether (for example dioxane

  or tetrahydrofuran), a ketone (e.g.

  ne), an amide (for example dimethylformamide) or a

  sulfoxide (for example dimethylsulfoxide), advantageously

  in the presence of an acid or a base. Suitable acids include organic acids such as p-toluenesulfonic acid or inorganic acids such as hydrochloric acid, nitric acid or sulfuric acid. Suitable bases include inorganic bases such as alkali metal hydroxides or carbonates (eg, sodium or potassium hydroxide or carbonate). You can also use an acid

  aqueous or aqueous base as the reaction solvent.

  The hydrolysis can advantageously be carried out at a temperature in the range of -10 ° C to 150 ° C, for example at reflux. When R represents a C1-C4 alkyl or aryl group, the RO- anion is advantageously formed from a corresponding ROH alcohol by using an inorganic base such as an alkali metal (for example sodium metal) or a hydride alkali metal (eg sodium hydride). The reaction with the anion

  formed in situ can conveniently be conducted at room temperature.

ambient temperature.

  In another embodiment of process (B), compounds of formula (I) in which X represents an SH group can be prepared by reaction of the halogenated compound of formula (I) with thiourea in a

  suitable solvent such as an alcohol (e.g.

  propanol) at an elevated temperature (e.g. at reflux), the reaction being followed by alkaline hydrolysis. Suitable bases which may be used include alkali metal hydroxides (e.g., sodium hydroxide). The reaction may be conveniently conducted according to the method of G. G. Urquart et al., Org. Syn. Coll. Flight. 3, 363 (1953), for example by refluxing the intermediate product with an aqueous solution

  of NaOH for about 0.25 to about 5 hours.

  In another embodiment of process (B), compounds of formula (I) in which X represents a hydrogen atom may be prepared by reduction of the halogenated compound of formula (I) using a reducing system which does not affect the rest of the molecule. Suitable reducing agents that can be used to drive the desired dehalogenation reaction include the zinc metal / water system

  with which the method described by J.R.

  Marshall et al. In J. Chem. Soc., 1004 (1951).

  Alternatively, the reaction can be carried out by

  photolysis in a suitable solvent such as tetrahydro-

  furan containing 10% triethylamine and, advantageously,

  in a Rayonet photochemical reactor (2537A)

  according to the procedure described by V. Nair and collabora-

  in J. Ora. Chem., 52, 1344 (1987).

  According to yet another embodiment of process (B), compounds of formula (I) in which X represents a halogen atom from a different halogenated compound of formula (I) can be prepared by processes conventional exchange between halides. Alternatively, when X is chlorine, this substituent may be replaced by other halogen atoms using

  various chlorides of p- (halo) benzene diazonium according to

to well-known methods.

  Compounds of formula (I) wherein X is SR or R is (1-4C) alkyl or aryl may be prepared from thiols

  using standard operating procedures

  alkylation or arylation, as described, for example

  in U.S. Patent No. 4,383,114.

  Compounds of formula (I) in which Z represents a hydroxyl group may be conveniently prepared from a corresponding compound of formula (I) wherein Z is NH 2 by reaction with

  nitrous acid, using, for example, the

  used by J. Davoll in J. Amer. Chem. Soc., 73, 3174

(1951).

  Many of the reactions described above have

  have been widely described in relation to nucleoside synthesis.

  purine derivatives, for example in Nucleoside Analogues - Chemistry, BiolocOv and Medical AlDlications, edited by R.T. Walker et al., Plenum Press, New York (1979), pages 193-223, the subject of which is incorporated herein by reference.

  is hereby incorporated by reference.

Pharmaceutically acceptable salts of the compounds of the invention may be prepared as described in U.S. Patent No. 4,383,114, incorporated herein by reference. Thus, for example, when it is desired to prepare an acid addition salt of a compound of formula (I), the product of any of the above processes can be converted to a salt by treatment of the resulting free base with a suitable acid, using conventional methods. Pharmaceutically acceptable acid addition salts can be prepared by reacting the free base with a suitable acid, optionally in the presence of a suitable solvent such as an ester (eg, ethyl acetate) or an alcohol (for example methanol, ethanol or isopropanol). Inorganic basic salts can be prepared by reacting the free base with a suitable base such as an alkoxide (for example sodium methoxide), optionally in the presence of a solvent such as

  than an alcohol (for example methanol). Pharmaceutical salts

  can also be prepared for

  from other salts, including other pharmaceutical salts

  acceptable, compounds of formula (I) in

  using conventional methods.

  A compound of formula (I) can be converted into

  a phosphoric ester or other pharmaceutical ester-

  acceptable by reaction with a phosphorylating agent

  such as POCl3 or with a suitable esterifying agent

  such as an acid halide or anhydride, as the case may be.

  An ester or salt of a compound of formula (I) can be converted to the corresponding compound, for example by hydrolysis. The compounds of formula (II) and their salts are novel compounds and constitute another particular

of the present invention.

  The compounds of formula (II) in which Z represents hydrogen or a hydroxyl group can be prepared directly from compound 2a to H2

HO'1 / \

  I. s * by reaction with an excess of a pyrimidine of formula (III) X x H2 NH N0 s (III)

Z N Y

  (where Y is a halogen atom such as chlorine and Z is hydrogen or a hydroxyl group) in the presence of an amino base such as triethylamine and in a

  alcoholic solvent (for example n-butanol), advantageously

at reflux.

  Compounds of formula (II) wherein Z is NH 2 can be prepared using the compound of formula 2a by reaction with an excess of a pyrimidine of formula (IV) X / N

} (IV)

H2N N Y

  (wherein Y is as defined in formula (III) above under conditions similar to those just described above for the preparation of compounds of formula (II) wherein Z is hydrogen or a hydroxyl group to form a compound of formula (V) XNII

H2N N H V)

HO-CH2 /

  which may be diazotized using a diazonium salt ArN 2 + E- (where Ar represents an aromatic group, for example p-chlorophenyl, and represents an anion, for example a halide anion such as chloride) in a solvent such as water, an organic acid such as acetic acid or their mixture, advantageously at a temperature of the order of room temperature to form a compound of formula (VI) X * N = N-Ar N

H2N N H (VI)

HO-CH2 \ / \

  I l (in which Ar has the definition which has just been given) which can be converted to the desired compound of formula CII) by reduction using for example a reducing metal such as zinc in the presence of a acid, for example acetic acid. It should be noted that the choice of the reducing agent depends on the nature of the group X.

  Compound 2a can be prepared from la-

  acetylamino-3a-acetoxy-methylcyclopent-2-ene (.a), a precursor endowed with flexibility of use, by hydrolysis in the presence of a mild base such as an alkaline earth metal hydroxide. A particularly convenient synthesis of

  compounds of formula (I) via compounds

  chlorinated compounds of formula (II) is illustrated below.

Z626002

Ci N ZNNH AcO-Ac

II I II

the 2a Ci1 X

1 I 1 I

* -o * - Cl / \\ / \

H2NN2H2NN'H -> ZN N

lt2Nle a

H2N N

I I II I

  o. Compound 2a and compounds of formulas (V) and (VI) are novel intermediates and constitute other features of the present invention. Compound la is a known compound described in U.S. Patent No. 4,138,562. When the compound of formula (I) is desired as the individual isomer, it can be obtained either by

  duplication of the final product, either by stereospheric synthesis

  specific from the isomerically starting material

  pure or any suitable intermediate compound.

  Duplication of the final product or a

  intermediate compound or the starting material corresponding to

  dante can be carried out by any convenient method known in the art: see for example "Stereochemistry of Carbon Compounds", E.L. Eliel (McGraw Hill, 1962) and

  "Tables of Resolving Agents", S.H. Wilen.

  A suitable method for obtaining

  compounds of formula (I) of chiral purity is the transfor-

  enzymatic mixture of a racemic mixture of the compound or a precursor of the compound. By such a process, (+) and (-) compounds of formula (I) can be obtained in optically pure form. Suitable enzymes include

  deaminases such as adenosine deaminase.

  Further details of the invention emerge from the following detailed examples in which the elemental analyzes were carried out by the M-H-W Laboratories of Phoenix, AZ. The melting points were determined on a Mel-Temp apparatus and corrected. Nuclear magnetic resonance spectra were recorded in DMSO-D6 on Jeol FX 90QFT or Nicollet NT300 spectrometers. The chemical drifts are expressed in ppm relative to the tetramethylsilane used as reference substance. Infrared spectra were determined on

  KBr pellets with a Nicollet 50XC FT- spectrometer

  IR and ultraviolet spectra were determined on a Beckmann DU-8 spectrophotometer. Mass spectra were recorded using an MS-30 Mass Spectrometer from AEI Scientific Apparatus Limited. Thin layer chromatography (TLC) was performed on 0.25 mm layers of Merck silica gel (37 & 62 μm particles). All chemicals and solvents are

  quality for analysis, unless otherwise specified.

  The term "active ingredient" used in the Examples

  denotes a compound of formula (I) or a pharmaceutical derivative

acceptable for this compound.

Example 1

  () - (4α) -4-r (5-Amino-6-chloro-4-pyrimidinyl) -aminol-2-

cyclopentenylcarbinol (3a)

  A mixture of 1-acetylamino-3α-acetoxymethyl

  cyclopent-2-ene (3.0 g, 15 mmol) and aqueous barium hydroxide (0.5 N, 300 ml) was refluxed.

  for one night. After cooling, it was neutralized

  with dry ice. The precipitate was filtered off and the aqueous solution was concentrated to dryness. The residue was extracted with absolute ethanol and reconcentrated to give Compound 2a as a

colorless syrup, 1.6 g (14 mmol).

  To this syrup was added 5-amino-4,6-

  dichloropyrimidine (4.59 g, 28 mmol), triethylamine (4.2 g, 42 mmol) and n-butanol (50 ml) and the mixture was refluxed for 24 hours. The volatile solvents were removed, the residue was absorbed on

  silica (7 g), packed in a chromatography column

  flash (4.0 x 12 cm) and eluted with a mixture of chloroform and methanol (20: 1) to give 2.69 g (74%)

  of compound 3a melting at 130-132 ° C. An analytical sample

  obtained by recrystallization from ethyl acetate (EtOAc), mp 134-135 ° C, mass spectrum (30 ev, 200 ° C): m / e 240 and 242 (M + and M + +) 2) 209 (M + -31), 144 (B +); infrared spectrum: 3600-2600 (OH), 1620, 1580 (C = C, C = N); analysis (C 10 H 13 ClN 4) C, H, N.

Example 2

  () - (4α) -4-r [(2-Amino-6-chloro-4-fluorimidinyl) amino] -2-

  cyclopentenylcarbinol (4a) 2-Amino-4,6-dichloropyrimidine (3.74 g, 22.8 mmol), triethylamine (15 ml) and crude triethylamine (15 ml) were added to -14 ml of crude product 2a (Example 1) and n-butanol (75 ml) and the mixture was refluxed for 48 hours. Volatile solvents were removed, the residue was treated with methanol to separate the undissolved byproduct (pyrimidine double nucleoside). The methanolic solution was absorbed on silica gel (8 g), packed in a column (4.0 x 14 cm) and eluted with a mixture of chloroform and methanol (40: 1) to give 1.52 g ( 42%) of crude product 4a. The product was recrystallized from ethyl acetate to give compound 4a; mp 132-134 ° C, mass spectrum (30 ev, 200 ° C): m / e 240 and 242 (M + and M + + 2), 209 (M + -31), 144 (B +); infrared spectrum: 3600-3000 (NH 2, OH), 1620, 1580 (C = C, C = N); anal. (C10H13ClN4) C, H, N.

Example 3

  () - (la) -4- <- (2-Amino-6-chloro-5- (4-chlorophenyl) azol-4-

  pvrimidinyl-amino) -2-cyclopentenylcarbinol (5a) A cold diazonium salt solution was prepared from p-chloroaniline (1.47 g, 11.5 mmol) in 3N HCl (25 ml) and sodium nitrite. sodium (870 mg, 12.5 mmol) in water (10 ml). This solution was added to a mixture of Compound 4a (2.40 g, 10 mmol), acetic acid (50 mL), water (50 mL), and sodium acetate trihydrate (20 g). The reaction mixture was stirred overnight at room temperature. The yellow precipitate was filtered and washed with cold water until neutral, then air dried under the hood to give 3.60 g (94%) of compound 5a melting at 229 ° C (decomposition). ). The analytical sample was obtained from a mixture of acetone and methanol (1: 2), mp 241-243 ° C (decomposition). Mass Spectrum (30 ev, 260C): m / e 378 and 380 (M + and M + + 2), 282 (B +); infrared spectrum: 3600-3000 (NH 2, OH), 1620, 1580 (C = C, C = N); analysis (C16H16Cl2N6O) C, H, N.

Example 4

  () - (la) 4a) -4- (2, 5-Diamino-6-chloro-4-pyrimidinyl) aminol-

  2-cyclopentenylcarbinol (6a) A mixture of compound 5a (379 mg, 1 mmol), zinc powder (0.65 g, 10 mmol), acetic acid (0.32 ml), water (15 ml ) and ethanol (15 ml) was refluxed under nitrogen for 3 hours. The zinc was removed and the solvents evaporated. The residue was absorbed on silica gel (2 g), packed in a column (2.0 × 18 cm) and eluted with CHCl 3 -MeOH.

  (15: 1). We got a pink syrup. Purification

  Subsequent addition to a mixture of methanol and ether gave compound 6a as pink crystals, 170 mg (66%), mp 168170 ° C, mass spectrum (30 ev, 220 ° C): m.p. 255 and 257 (M + and M + + 2) 224 (M + -31) 159 (B +), infrared spectrum: 3600-3000 (NH 2, OH) 1620, 1580 (C = C, C = N), anal ( C10H14ClN5) C, H, N

Example 5

  () - (1α, 4α) -4- (6-Chloro-9H-purine-9-yl) -2-cyclopentenyl

  carbinol (7a) A mixture of compound 3a (1.30 g, 5.4 mmol),

  of triethyl orthoformate (30 ml) and hydrochloric acid

  (12 N, 0.50 mL) was stirred overnight at room temperature. The solvent was evaporated at 35 ° C in vacuo. To the residue was added an aqueous solution of hydrochloric acid (0.5 N, 30 ml) and the mixture was stirred for 1 hour, neutralized. at pH 7-8 with 1 N sodium hydroxide and was absorbed on silica gel (8 g), packed in a column (4.0 x 8 cm) and eluted with a mixture of chloroform and methanol (20: 1) to give white crystals of compound 7a, 1.12 g (82%). The crude product was recrystallized from ethyl acetate to give 7a, m.p. 108-110 ° C, mass spectrum (30 ev, C): m / e 250 and 252 (M + and M + + 2), 219 (M + -31), 154 (B +); infrared spectrum: 3600-2800 (OH), 1600 (C = C, C = N); anal. (C11H11ClN4) C, H, N.

Example 6

  () - (1α, 4α) -4- (6-Hydroxy-9H-purin-9-yl) -2-cyclopentenyl

  carbinol (8a) A mixture of Compound 7a (251 mg, 1 mmol) and aqueous sodium hydroxide (0.2 N, 10 ml) was refluxed for 3 hours. After cooling, the pH of the reaction mixture was adjusted to 5-6 with acetic acid. The reaction mixture was absorbed on silica gel (2 g), packed in a column (2.0 x 11 cm) and eluted with a mixture of CHCl3 and MeOH (10: 1), yielding 105 mg (45 ml). %) of compound 8a. The crude white product was recrystallized from a mixture of water and methanol (3: 1) to give compound 8a, m.p. 248-250 ° C (dec.), Mass spectrum (30 ev, 300 ° C): m / e 232 (M +), 214 (M + -18), 136 (B +); infrared spectrum: 3600-2600 (OH), 1680, 1600 (C = O, C = C, C = N); anal. (C1H12N4O2) C, H, N.

Example 7

  () - (a) 4acl-4- (6-Amino-9H-purine-9-yl) -2-cyclopentenyl

  carbinol (9a) Liquid ammonia was transferred to a bomb containing a solution of compound 7a (250 mg, 1 mmol) in methanol (5 mL) at -80 ° C. The bomb was closed and heated at 60 ° C for 24 hours. Ammonia and methanol were evaporated and the residue was recrystallized from water to give slightly off-white crystals of Compound 9a, 187 mg (81%), mp 198-200 °. C. Mass spectrum (30 ev, 210 ° C); m / e 231 (M +), 213 (M + -18), 135 (B +); infrared spectrum: 3600-2600 (NH 2, OH), 1700, 1600 (C = C, C = N); anal. (C11H13C50) C, H, N.

Example 8

  f) -fla.4a) -4- (6-Mercapto-9H-purin-9-yl) -2-cyclopentenyl-

  carbinol (10a) A mixture of compound 7a (125 mg, 0.5 mmol), thiourea (40 mg, 0.64 mmol) and n-propanol (5 ml)

  refluxed for 2 hours. After cooling

  The precipitate was isolated by filtration, washed with n-propanol and dissolved in sodium hydroxide (1 N, ml). The pH of the solution was adjusted to 5 with acetic acid. The crude compound 10a (90 mg, 73%) was

  isolated again, mp 260-262 C (decomposed

  tion), and it was recrystallized from N, N-dimethylfor-

  mamide to give compound 1o, mp 263-265-C (decomposition). Mass Spectrum (30 ev, 290 C): m / e 248

  (M +), 230 (M + -18), 152 (B +); infrared spectrum: 3600-

  3200 (OH), 3100, 2400 (SH), 1600 (C = C, C = N); anal.

(ClIH12N4O5) C, H. N.

Example 9

  () - (1α.4a) -4- (2-Amino-6-chloro-9H-purin-9-yl) -2-cyclopent

  Tenylcarbinol (13a) A mixture of Compound 6a (1.41 g, 5.5 mmol), triethylorthoformate (30 mL) and hydrochloric acid (12N, 1.40 mL) was stirred for one night. The suspension was dehydrated under vacuum. Dilute hydrochloric acid (0.5 N, 40 ml) was added and the mixture was stirred for 1 hour at room temperature. The mixture was neutralized to pH 8 with 1 N sodium hydroxide and absorbed on silica gel (7.5 g) packed in a column (4.0 x 10 cm) and eluted with a mixture chloroform and methanol (20: 1) to give slightly off-white crystals of compound 13a, 1.18 g (80%). The crude product was recrystallized from ethanol to give compound 13a, mp 145-147 ° C. Mass Spectrum (30 ev, 220 ° C): m / e 265 and 267 (M + and M + + 2), 235 (M + -30), 169 (B +); infrared spectrum: 3600-2600 (NH 2, OH), 1620-1580 (C = C, C = N); anal. (ClIH12N5OC1.3 / 4H2O) C, H, N.

Example 10

  () - (4α) -4- (2-Amino-6-hydroxy-9H-purin-9-yl) -2-

  cyclopentenylcarbinol (14a) A mixture of compound 13a (266 mg, 1 mmol) and aqueous sodium hydroxide (0.33 N) was refluxed for 5 hours, absorbed on silica gel (2 g), conditioned in a column (2.0 x 7.5 cm) and eluted with a mixture of chloroform and methanol (5: 1). The crude product was recrystallized from a mixture of methanol and water (1: 4) to give white crystals of 14a, 152 mg (61%), mp 254-256 ° C (dec). Mass spectrum (30 ev, 200 C): m / e 247 (M +), 217 (M + -30), 151 (B +); infrared spectrum:

  3600-2600 (NH 2, OH), 1700, 1600 (C = O, C = C, C = N); anal.

  (ClHH13N5O2.3 / 4H2O) C, H, N. Example 11

  (6α, 4α-4- (2,6-Diamino-9H-purine-9-yl) -2-cyclo-dienenyl)

  carbinol (15a) Liquid ammonia was transferred into a solution of compound 13a (265 mg, 1 mmol) in methanol (10 ml) at -80 ° C in a bomb. The bomb was closed and heated at 75 C for 48 hours. Ammonia and methanol were evaporated. The residue was absorbed on silica gel (2 g), packed in a column (2.0 x cm) and eluted with a mixture of chloroform and methanol (15: 1). The crude product was recrystallized from ethanol to give 196 mg (80%) of compound 15a, m.p. 152-155 ° C. Mass Spectrum (30 ev, 200 ° C): m / e 246 (M +), 229 ( M + -17), 216 (M + -30), 150 (B +); infrared spectrum: 3600-3000 (NH 2, OH), 1700, 1650, 1600 (C = O, C = C, C = N); anal. (ClHH14N60) C, H, N.

Example 12

  (1S, 4R) -4- (2,6-Diamino-9H-purine-9-yl) -2-cyclopentenyl-

carbinol

  [(LS, 4R) -4- (2,6-Diamino-9H-purin-9-yl) -2-cyclopenten

methanol]

  (a) Intermediate Compound 1: (1R, 2S, 3R, 5R) -3- [6-amino]

  9H-purin-9-yl] -5 - [((1,1L-dimethylethyl) dimethylsilyloxy) -

  methyl] -1,2-cyclopentanediol (-) Aristeromycin1 (12,505 g), t-butyldimethylsilyl chloride

  (7.8 g) and imidazole (12.96 g) in dimethylformate

  Anhydrous mamide (85 ml) was stirred at room temperature for 2.5 hours. The resulting solution was diluted with ethyl acetate (500 ml), then washed with water (3 x 100 ml) and brine (50 ml) before a white solid material was formed. separates by crystallization. This solid material was collected by filtration, washed with ethyl acetate and then dried under vacuum to give the title product (3.92 g); proton magnetic resonance (DMSO-d6) 8.15 (1H), 8.09 (1H), 7.19

  (2H), 5.00 (1H), 4.72 (1H), 4.69 (1H), 4.36 (1H), 3.85

  (1H), 3.67 (2H), 2.23 (1H), 2.09 (1H), 1.79 (1H), 0.89

(9H), 0.07 (6H).

  1 Journal of the American Chemical Society 1983, vol. 105

4049-4055.

  (b) Intermediate Compound 2: (4R, 3aS, 6R, 6aR) -4- [6-amino]

  9H-purin-9-yl] -6 - [((1,1-dimethylethyl) dimethylsilyloxy) -

  methyl] -3a, 5,6,6a-tetrahydro-4H-cyclopenta-l, 3-dioxole-2

  thione A stirred suspension of Intermediate Compound 1 (3.45 g) in dry dimethylformamide (56 ml) was treated with 1,1-thiocarbonyldiimidazole (3.3 g) to give a yellow solution. After 15.5 hours at room temperature, the resulting solution was combined with the solution from a previous test (6% scale) and the solvent was evaporated off.

  tion. The residual oil was diluted with ethyl acetate (100 ml) then washed with water (2 x 20 ml) and brine (2 x 20 ml), dried (MgSO 4) and evaporated to dryness. giving a yellow solid substance. This solid was washed with diethyl ether (25 ml) then collected by filtration, further washed with ether (25 ml) and dried under vacuum to give the title product as a solid substance. pale cream color (3.61 g); A max (ethanol) 240.0 nm (E 1 cm459) proton magnetic resonance (DMSO-d6) 8.27 (1H), 8.13

  (1H), 7.33 (2H), 5.81 (1H), 5.37 (1H), 5.28 (1H), 3.78

  (2H), 2.60 (1H), 2.28 (2H), 0.90 (9H), 0.09 (6H).

  (c) Intermediate Compound 3: (R, 4'S) -9- [4 - (((1,1-

  Dimethylethyl) dimethylsilyloxy) methyl) -2-cyclopenten-1-

  yl] -9H-purine-6-amine A solution of Intermediate Compound 2 (3.57 g) in anhydrous tetrahydrofuran (25 ml) was treated with a solution of 1,3-dimethyl-2-phenyl-1,3 2-diazaphospholidine (4.94 g) in anhydrous tetrahydrofuran (10 ml) and then stirred at room temperature

  for 8.75 hours. The solvent was evaporated off

  tion. The residual oil was combined with that from a previous test (at the 40% scale) and then subjected to silica column chromatography (200 g, Merck 7734), eluted with chloroform then with mixtures of chloroform and ethanol giving a white solid. This solid was washed with diethyl ether (25 ml) and collected by filtration. The solid was further washed with ether (10 ml) and dried under vacuum to give the title product (1.47 g); Amax (ethanol) 261.4 nm (E 1% 443); 1 cm proton magnetic resonance (DMSO-d6), 8.14 (1H), 8.00

  (1H), 7.20 (2H), 6.12 (1H), 5.95 (1H), 5.60 (1H), 3.66

  (2H), 2.96 (1H), 2.69 (1H), 1.65 (1H), 0.74 (9H), 0.02

(6H).

  (d) Intermediate Compound 4: 1-Oxide (R, 4'S) -9- [4-

  (((1,1-dimethylethyl) dimethylsilyloxy) methyl) -2-cyclopentyl

  tene-1-yl] -9H-purine-6-amine A solution of Intermediate Compound 3 (1.37 g) in chloroform (30 ml) was treated with mchloroperoxybenzoic acid (1.29 g) at 80.degree. -90% then stirred at room temperature for 3 hours. The solvent was evaporated off and the residual gum was dissolved in ethyl acetate (10 ml). A

  white solid separated by crystallization.

  This solid substance and the material collected by

  Evaporation of the filtrate was dissolved in chlorine

  form (100 ml), then the solution was washed with saturated aqueous sodium bicarbonate solution (3 x 10 ml) and brine (2 x 10 ml). The aqueous wash liquors were re-extracted with chloroform (50 ml). The combined organic solutions were dried (MgSO4) and then evaporated to a solid. This solid material was washed with diethyl ether (25 ml) and collected by filtration. The white solid was further washed with ether (10 ml) and dried under vacuum to give the title product (1.16 g); Amax (ethanol) 235.4 nm (EI% 1324), 1% 1% 1cm 263.2 r. (E1 cm 248), 300.2 nm (E1 cm 75); proton magnetic resonance (CDC13) 8.72 (1H), 8.02 (1H), 7.16

  (2H), 6.21 (1H), 5.87 (1H), 5.72 (1H), 3.68 (2H), 3.04

  (1H), 2.82 (1H), 1.74 (1H), 0.89 (9H), 0.06 (6H).

  (e) Intermediate Compound 5: (1'R, 4'S) Hydrobromide

  [4 - (((1,1-dimethylethyl) dimethylsilyloxy) methyl) -2-

  cyclopenten-l-yl] -2-imino-l, 2-dihydro [1,2,4] oxadiazolo-

  [3,2-i] -9H-purine An ice-cold stirred suspension of Intermediate Compound 4 (1.08 g) in methanol (20 ml) was treated with a solution of cyanogen bromide (0). 34 g) in methanol (20 ml) added in minutes. After 15 minutes, the slurry was allowed to warm to room temperature resulting in a solution. After 90 minutes, the solvent was removed by evaporation. The residue was washed with diethyl ether (25 ml) and collected by filtration. The solid was further washed with ether (25 ml) and dried under vacuum to give the title product (1.37 g): Amax (ethanol) 228.2 nm (E 1% 530), 285.2 nm (E cm 445); 1cm resonance At proton magnetic cm (CDC13) 10.20 (1H), 10.02 (1H), 8.37

  (1H), 6.25 (1H), 6.01 (1H), 5.90 (1H), 3.69 (2H), 3.05

  (1H), 2.86 (1H), 1.73 (1H), 0.86 (9H), 0.03 (6H).

  (f) Intermediate compound 6: (R, 4'S) -9- [4 - (((1,1-

  Dimethylethyl) dimethylsilyloxy) methyl) -2-cyclopenten-1-

  Yl] -6-cyanimino-1,6-dihydro-1-methoxy-9H-purine A solution of Intermediate Compound 5 (1.36 g) in dimethylformamide (10 ml) was stirred at room temperature.

  the ambient temperature and then treated with triethyl

  amine (1.2 ml). After 40 minutes, we added

  iodomethane (0.54 ml) to give a yellow solution.

  After 3.75 hours, the solvent was removed by evaporation. The residue was partitioned between ethyl acetate (100 ml) and water (20 ml). The organic solution was further washed with water (2 × 20 ml) and brine (20 ml), dried (MgSO 4) and evaporated to a solid. This solid material was washed with diethyl ether (25 ml) and collected by filtration. This white solid was further washed with ether (10 ml) and then dried under vacuum to give the title product (0.865 g): λ max (ethanol) 227.2 nm (E 1% 449), 287.0 nm (E1% 544); 1cm 1cm magnetic resonance protons 8.23 (1H), 7.96 (1H), 6.24 (1H),

  , 85 (1H), 5.65 (1H), 4.21 (3H), 3.66 (2H), 3.04 (1H), 2.77

  (1H), 1.68 (1H), 0.88 (9H), 0.05 (6H).

  (g) Intermediate Compound 7: (R, 4'S) -9- [4 - (((1,1-

  Dimethylethyl) dimethylsilyloxy) methyl) -2-cyclopenten-1-

  yl] -6-methoxyamino-9H-purine-2-amine A solution of Intermediate Compound 6 (802 mg) and 1,8-diazabicyclo [5.4.0] undec-7-ene (0.45 ml) in ethanol (80 ml) was stirred and heated to reflux. The heating was stopped after 9 hours and the solution was kept at room temperature overnight. The solvent was removed by evaporation. The residual oil was combined with that from a previous test (4% scale) and then the mixture was subjected to silica column chromatography (40 g, Merck 9385), eluted with chloroform. then blends of chloroform and ethanol to give a foam. This foam was triturated with diethyl ether (10 ml) and the solid material. The resultant was collected by filtration. The solid was further washed with ether (5 ml) and dried under vacuum to give the title product (594 mg); max (ethanol) 282.2 nm (EI% 409); proton magnetic resonance 1cm (DMSO-d6) 9.76 (11H), 7.32 (1H), 6.53

  (2H), 6.08 (1H), 5.88 (1H), 5.26 (1H), 3.72 (3H), 3.61

  (2H), 2.90 (1H), 2.50 (1H), 1.52 (1H), 0.83 (9H), 0.02

(6H).

  (h) Intermediate Compound 8: (1S, 4R) -4- [2-Amino-6-

  Methoxyamino-9H-purin-9-yl] -2-cyclopentene-methanol A solution of Intermediate Compound 7 (356 mg) in tetrahydrofuran (35 ml) was stirred at room temperature and then treated with fluoride.

  tetrabutylammonium (1.0 M solution in tetrahydrofuran

  ne, 1.4 mi). After 90 minutes, the reaction was quenched with water (1 ml) and the solvents were evaporated off. The residual oil was subjected to silica column chromatography (20 g, Merck 7734), eluted with chloroform and then with mixtures of chloroform and ethanol, and there was thus obtained the title product in the form of a solid substance (243 mg); kmax (buffer at pH 6) 280.2 nm (E1 cm 534); proton magnetic resonance cm (DMSO-d6) 9.75 (1H), 7, 39 (1H), 6.52

  (2H), 6.10 (1H), 5.84 (1H), 5.27 (1H), 4.73 (1H), 3.40

  (2H), 2.83 (1H), 2.55 (1H), 1.52 (1H).

  (LS.4R) -4-R2.6-Diamino-9H-purin-9-yll-2-cyclopentènecar-

  A stirred, ice-cooled solution of Intermediate Compound 8 (210 mg) in water (10 ml) and tetrahydrofuran (50 ml) was treated with aluminum amalgam [prepared from of aluminum (237 mg) and 0.5% aqueous mercuric chloride], added in small quantities over 15 minutes. After 40 minutes, the stirred mixture was allowed to warm to room temperature. After 15 hours, the resulting mixture was filtered through Kieselguhr to remove insolubles. These materials were washed with a mixture of water and tetrahydrofuran (1: 5, ml). The combined filtrates were evaporated. The residue was subjected to silica column chromatography (10 g, Merck 9385), eluted with chloroform-ethanol mixtures to give the title product as the title product.

  foam form (159 mg); [a] D-81 '(c 1.04, methanol)

  nol); Amax (buffer pH 6) 255.0 nm (E1% 302), 280.8 nm (E1% 1 cm (E1 cm 381), proton magnetic resonance (DMSO-d6)

  7.61 (1H), 6.66 (2H), 6.10 (1H), 5.87 (1H), 5.76 (2H), 5.38

  (1H), 4.76 (1H), 3.45 (2H), 2.87 (1H), 2.60 (1H), 1.60

(1H).

Example 13

  (LS, 4R) -4- (2-Amino-6-hydroxy-9H-purin-9-yl) -2-cyclopentyl

ténylcarbinol

  (R, 4'S) -2-Amino-1,9-dihydro-9- [4-hydroxymethyl-2-

  cyclopenten-1-yl] -6H-purin-6-one A hazy solution of the title compound of Example 12 (144 mg) in 0.1 M buffer at pH 6 (10 ml) (prepared from 28 , 4 g of disodium orthophosphate in 2 liters of water, adjusted to orthophosphoric acid) was treated with an adenosine deaminase solution (0.5 ml, 778 units) in a 50% glycerol mixture and 0.01 M potassium phosphate, pH 6.0, then stirred and heated to 37 °. After 18.5 hours, the resulting slurry was refrigerated. The collected solid was recrystallized from water to give the title product as a white solid (86 mg); [aID -49 '(c, 0.5, dimethylsulfoxide); Amax

3 5 1

  (buffer at pH 6) 252.6 nm (E1 cm 531), proton magnetic resonance 1cm (DMSO-d6) 10.60 (1H), 7.60 (1H), 6.47 (2H),

  6.10 (1H), 5.86 (1H), 5.33 (1H), 4.72 (1H), 3.45 (2H), 2.59.

(1H), 1.58 (1H).

Example 14

  Preparation of enantiomers of (4al-4- (2-amino-6-hydroxyl)

  9H-purin-9-yl) -2-cvclopenténylcarbinol

  (a) (1S, 4R) -4- (2-Amino-6-hydroxy-9H-purine-9-yl) -2-

  cyclopentenylcarbinol The diamino analog (100 mg) (Example 11) was dissolved in 3 ml of 0.05 M K2PO4 buffer (pH 7.4) and warm (50 ° C). It was allowed to cool. the solution to the

  room temperature and 40 units of adenosine were added.

  deaminase (Sigma, Type VI, intestinal mucosa of calf).

  After three days of incubation at room temperature, a precipitate formed which was collected by filtration; yield 18.2 mg. The filtrate was concentrated to a volume of 1.5 ml and refrigerated for 2 days. An additional amount of solid material was obtained by filtration in an amount of 26.8 mg. The two solid fractions were recrystallized from water

  giving the product of the title in its pure state, melting at 269-

272 C, [α] D -62.1 (c 0.3, MeOH).

  (b) (1R, 4S) -4- (2-Amino-6-hydroxy-9H-purin-9-yl) -2-

  Cyclopentenylcarbinol F iltrates of the preparation of the isomer

  11S, 4R (Example 14a) were combined and evaporated to dryness.

  The unchanged diamine starting material was separated on a flash column packed with silica gel using a 10% mixture of methanol and chloroform. The diamino compound was dissolved in 0.05M K2PO4 pH 7.4 buffer (15 ml) and 800 units of adenosine deaminase added. The solution was incubated for 96 hours at 37 ° C. Thin layer chromatography indicated that some unreacted product remained. The solution was heated in boiling water for 3 minutes and filtered to remove the denatured protein. Another 800 units of adenosine deaminase were added and repeated

  process. The solution freed from the proteinaceous matter

  that was evaporated to dryness and the product was crystallized from water. The title product in the form of a white solid was collected by filtration in water, mp 265-270 °. [α] 24 + 61.1 (c 0.3, MeOH).

Example 15

  () - (lc.4a) -4- (2-Amino-6-hydroxy-9H-durin-9-yl) -2-

  cyclopentenylacetoxycarbinol Acetic anhydride (0.06 ml, 0.6 mmol) was added to a suspension of the product of Example 10 (130 mg, 0.50 mmol) and 4-dimethylaminopyridine (5 mg, 0, 04 mmol) in a mixture of acetonitrile (6 ml) and triethylamine (0.09 ml, 0.66 mmol). The mixture was stirred at room temperature for 3 hours. Methanol (1 ml) was added to stop the reaction. The solution was concentrated and absorbed on silica gel (1.5 g) packed on a column (2.0 x 12 cm) and eluted with a mixture of chloroform and methanol ( 20: 1). The product fractions were collected and concentrated to give a white solid. The solid product was washed with a mixture of methanol and ethyl acetate: yield 123 mg (85%). Another purification in methanol gave the title product

  in the form of acicular crystals melting at 237-239 C.

Anal. (C13H15N5O3) C, H, N.

Example 16

  (1S, 4R) -4) 2-Amino-9H-purine-9-yl-2-cyclopentenylcarbinol A solution with stirring, cooled with

  ice, (1S, 4R) -4- [2-amino-6-methoxyamino-9H-purine-9-

  yl] -2-cyclopentene-methanol (Intermediate Compound 8, Example 12) (1.202 g) in tetrahydrofuran (250 ml) and

  water (50 ml) was treated with aluminum amalgam

  nium (prepared from aluminum (1.761 g) and 0.5% aqueous mercuric chloride) added in small portions over 1 hour and 47 minutes. After 35 minutes, the stirred mixture was allowed to warm to room temperature. After 16 hours and 50 minutes further aluminum amalgam (prepared from 235 mg of aluminum) was added over 14 minutes. After another 4 hours and 10 minutes, the resulting mixture was filtered through Kieselguhr to remove insoluble matter. The latter were washed with a mixture of tetrahydrofuran and water (5: 1, 300 ml). The combined filtrates were evaporated leaving a yellow foam. The foam was subjected to silica column chromatography (33.8 g, Merck 7734) prepared in chloroform and eluted with chloroform-ethanol mixtures to give several fractions (578 mg, 420 mg, 40 mg). The two largest fractions were crystallized separately in isopropanol. The filtrates were pooled with the smallest fraction of the column and the mixture was subjected to preparative thin layer chromatography (Merck 5717) developed three times.

  in a mixture of chloroform and methanol 10: 1.

  The plates were eluted with ethyl acetate and with a mixture of ethyl acetate and ethanol (1: 1) to give a brown solid (45 mg). The solid was subjected to silica column chromatography (2.7 g, Merck 7734), prepared in chloroform and eluted with mixtures of chloroform, methanol and triethylamine to give a gum (17 mg). After unsuccessful crystallization in isopropanol and a charcoal treatment in methanol,

  an aqueous solution of the collected material was.

  freeze-dried giving the titre (15 mg).

  Proton magnetic resonance (DMSO-d6) 1.62 (1H), 2.63 (1H), 2.89 (1H), 3.45 (2H), 4.73 (1H), 5.48 (iH) , 5.91 (1H), 6.14 (1H), 6.50 (2H), 7.98 (1H), 8.57 (1H). Spectrum

Mass, [MH] + 232.

  Example 17 Formulations for tablets A. The following formulation is prepared by wet granulation of the ingredients with a solution of povidone in water, drying and sieving, and

  addition of magnesium stearate and compression.

  ma / tablet (a) Active ingredient 250 (b) Lactose B.P. 210 (c) Povidone B. P. (d) Sodium salt of starch glycolate (e) Magnesium stearate B. The following formulation is prepared by

* direct compression; lactose is of the type for compres-

direct flow.

  mg / comDrime Active Ingredient 250 Lactose 145 Avicel 100 Magnesium Stearate 5 C. (Regulated Release Formulation) The formulation is prepared by wet granulation of the ingredients (below) with a solution of povidone in water, drying and sieving followed by the addition of stearate

magnesium and a compression.

  ma / tablet (a) Active ingredient 500 (b) Hydroxypropyl methylcellulose (Methocel K4M, high quality) 112 (c) Lactose B.P. 53 (d) Povidone B.P. 28 (e) Magnesium stearate 7

700

Example 18

  Formulation for capsules A formulation for capsules is prepared by mixing the ingredients below and introducing the

  mixture in a hard gelatin capsule in two parts.

  mg / capsule Active Ingredient 125 Lactose 72.5 Avicel 50 Magnesium Stearate 2.5

Example 19

  Injectable Formulation Active Ingredient 0.200 g 0.1 M sodium hydroxide solution, enough to adjust the pH to about 11 Sterilized water, sufficient for 10 ml The active ingredient is suspended in a small amount of water (which can be heated) and the pH is adjusted to about 11 with sodium hydroxide solution. The volume of the water is then added and filtered through sterile quality membrane into a sterile 10 ml glass vial which is closed with stoppers.

sterile topped with capsules.

  Example 20 Suppository mg / suppository Active Ingredient (63 & m) 250 Hard Fat, B.P. 1770 One fifth of hard fat is melted

  in a water-jacketed container, at a temperature of

  maximum of 45 ° C. The active ingredient is sieved through a 200 μm sieve and added to the molten base by stirring using a high shear stirrer.

  until a homogeneous dispersion is obtained. In hand-

  holding the mixture at 45 ° C, the remaining hard fat is added to the suspension and stirred to obtain a homogeneous mixture. The entire slurry was passed through a 250-gram stainless steel sieve and continued to stir, allowed to cool to 40 ° C. Working at 38-40 ° C., 2.02 g of the mixture were charged. in suitable plastic molds of

  2 ml. The suppositories are allowed to cool to room temperature

ambient temperature.

  EXAMPLE 21 ANTIVIRAL ACTIVITY (A) Anti-HIV Assay The compounds of formula (I) were subjected to

  selective tests for the determination of anti-

  HIV at the National Cancer Institute, Frederick Cancer Research Facility, Frederick, Maryland (FCRF). The following are the usual procedures for selective study used by the FCRF. The protocol is divided into three parts, (I) preparation of infected cells and distribution between test plates, (II) preparation of drug dilution plates and distribution between test plates and (III) method of analysis XTT. See D.A. Scudiero et al., "A New Simplified Tetrazolium Assay for Cell Growth and Drug Sensitivity in Culture," Cancer Res.

48, 4827 (1988).

  I. Infection and Distribution of ATH8 Cells in Microtitre Trays Cells intended to be infected (normal lymphoblastic cell line that expresses CD4) are placed in 50 ml conical centrifuge tubes and treated for 1 hour with 1-2 μg / ml. ml of polybrene to

  C. The cells are then pooled by centrifugation

  for 8 minutes at 1200 rpm. The HIV virus, diluted tenth in a medium (RMPl-1640, 10% human serum or 15% fetal calf serum (FCS) supplemented with IL-2 and antibiotic) is added to obtain a I am 0.001. Medium alone is added to control cells not containing the virus. If a titre of infectious virus of 10-4 is allowed, an MOI of 0.001 represents 8 infectious viral particles per 10 000 cells. About 500,000 cells per tube were exposed to 400 μl of the virus dilution. The resulting mixture is incubated for 1 hour at 37 ° C in a mixture of air and CO2. Infected or uninfected cells are diluted to 1 x 10-4 (with human serum) or 2 x 10-4 (with fetal calf serum)

cell for 100 Ml.

  Infected or uninfected cells (100 μl) are distributed between appropriate cells of a 96-well, U-bottomed microtiter plate. Each compound dilution is tested in duplicate with infected cells. Uninfected cells are examined for drug susceptibility in a single cell for each compound dilution. Control cells lacking drug, infected and uninfected, are studied in triplicate. The alveoli B2 to G2 serve as controls containing the reagents and receive only the medium. The plates are incubated at 37.degree. C. in a mixture of air and carbon dioxide until

  moment of addition of the drug.

  II. Dilution and addition of the drug

  Dilution plates (microtiter plates)

  96-cell flat-bottomed cell) are treated overnight with phosphate buffered saline (PBS) or medium containing at least 1% FCS or 1% human serum (depending on the medium used in the assay) , from the day before the test. This "blocking" method is used to limit drug adsorption by the

  microtiter tray during the dilution process.

  The cells are completely filled with blocking solution and allowed to stand at room temperature in

  a humid chamber, under a hood.

  The dilution process is started by first diluting the test compound to 1:20. Blocked dilution plates are prepared by flashing the blocking solution and drying by absorption on a sterile gauze pad. All the cells of each plate are then filled with 225 l of the appropriate medium, by means of a liquid handling system Cetus. 25 l of each compound diluted 1:20 in row A of a blocked and charged dilution plate are then added by hand. Four compounds are added per dilution plate, which is sufficient to feed two test plates. The four compounds are then serially diluted 10-fold from row A to row H by means of a liquid handling system Cetus. The starting dilution of each

  compound in row A is, at this stage, equal to 1: 200.

  Dilution plates are kept on ice

  until they are used.

  Using a 6-micron multi-channel pipettor, 100 μl of each drug dilution is transferred to the assay plate which already contains 100 μl of cell-added medium. The final dilution in the test plate starts at 1: 400 (cells B4 to G4). This dilution (up to 0.25% DMSO) prevents DMSO used as a carrier from interfering with growth of the cells. Infected or uninfected cells lacking drug (alveoli B3-G3) and controls

  containing the reagents (B2 to G2) receive the medium alone.

   The two final compounds are then transferred from cells H7 to H12 to a second test plate, according to the same procedure. The test plates are incubated at 37 ° C. in a mixture of air and carbon dioxide for 7 to 14 days or until the controls containing the virus are lysed, by

macroscopic examination.

  III. Quantitative expression of the cytopathogenicity -validity and activity of the drug A. Re;

  1. Solution of 2,3-bis [2-methoxy-4- hydroxide

  nitro-5-sulfophenyl] -5 - [(phenylamino) carbonyl] -2H-tétrazo-

  epithelium. (XTT) - 1 mg / ml solution in medium without FCS.

  Keep at 4C. Prepare each week.

  2. Phenazine Methosulfonate (PMS) stock solution - can be prepared and stored frozen at -20 ° C until use. It must be prepared in saline buffered with

  phosphate at a concentration of 15.3 mg / ml.

  B. Microtitre Tetrazolium (MTA) Assay 1. Preparation of XTT-PMS Solution - XTT-PMS solution is prepared immediately prior to addition to the cells of the culture dish. The mother solution of PMS is diluted to 1: 100 (0.153 mg / ml). Diluted PMS is added to each milliliter of XTT needed to reach a final PMS concentration of 0.02 mM. A 50 M1 aliquot of the XTT-PMS mixture is added to each of the appropriate alveoli and the plate is incubated for 4 hours at 37 ° C. The plate covers are removed and replaced by adhesive shutters (Dynatech cat 001-010-3501). The closed plate is shaken on a microcentrifuge plate mixer and

  absorption is determined at 450 nm.

  IV. Results The single figure is a graphical representation of the percentage change of test cells relative to uninfected cells (%) for infected and uninfected cells, as a function of

  the concentration increase of the compound of Example 10.

  The results shown graphically in the single figure allow the calculation of an effective concentration (EC50) with respect to infected cells of about 0.15 Mg / ml, an inhibitory concentration (IC50) relative to normal cells. approximately 600 μg / ml and a therapeutic index (IT50) of about 667. A previous test conducted at the Southern Research Institute gave an IT50 of about 200 when

  MT-2 cells were cultured in the presence of H9 / HTLV-

  IIIB. The HIV virus inhibitory concentrations, determined as described above, are reproduced in Table 1 for the compounds of the Examples.

7, 9, 10, 11 and 14 (b).

TABLE 1

  Positioned E 0 DI50 IT50 cell 9a 7 MI-2 2.3 50 21.4 13a 9 MI-2 0.41 6.97 17.3 14a 10 MI-2 0.15 100 667 15a 11 MI'-2 2.9> 125> 42.7 (-) 14a 14 (b) CEM 0.66 189 284 The compounds of Examples 5 and 8 also have

  showed antiviral activity in this selective study.

  (B) Activity against the virus of the leukemia of the cat A selective study of antiviral activity against the virus FeLV-FAIDS was carried out in plates

  at 96 cells (corning) using cells

  81C dicatrices in Iscove-modified Dulbecco's medium supplemented with 10% heat-inactivated bovine fetal bovine serum (FBS). Twenty hours before the assay, the plates were seeded with 81C cells at 5 x 10 3 cells per well. On the day of the test, the cells were pretreated for 30 minutes at 37 ° C. with DEAE-dextran (25 μg / ml) in 0.1 ml of equilibrated Hanks salt solution. This solution was removed, followed by 0.1 ml of growth medium containing 32 FeLV-FAIDS TCID50 or 0.1 ml of

  growth medium alone, was added to each cell.

  The virus was allowed an absorption time of 1 hour and then 0.1 ml of test compound or positive control compound (2 ', 3'dideoxycytidine, ddC) or growth medium was added. The plates were incubated at 37 ° C. Cells were added fresh growth medium

  containing the compound on the fourth day after infection.

  The culture medium was completely changed and replaced with fresh medium containing the compound on the seventh day after infection. On the tenth day after infection, the cells were fixed with formalin, stained bright blue Coomassie R-250 at 0.1% and examined microscopically.

  to determine the cytopathic effect and cytotoxicity

  the drug. The compound of Example 10 showed a dose

DE50 of 1.9 g / ml.

  (C) Activity against mouse AIDS virus Falcon 6-cell tissue culture plates were seeded with 1.75 x 10 cells per well in a total volume of 2.5 ml of EMEM containing% inactivated FBS. & the heat. Twenty hours after cell seeding, the medium was decanted off and 2.5 ml of DEAE-dextran (25 μg / ml in phosphate buffered saline) was added to each well. The cultures were incubated at 37 ° C. for 1 hour, after which the DEAE-dextran cell was decanted and the cell layers were rinsed once with 2.5 ml of PBS. Controls consisting of normal cells were prepared with 2.5 ml of medium alone (without virus or drug). The control cultures containing the drug received 2.5 ml of medium containing the drug but not containing virus. Control cultures infected with the virus received 0.5 ml of the appropriate dilution of CAS-BR-M stock solution to produce countable plates plus 2.0 ml of medium. The test samples received 0.5 ml of the appropriate virus dilution plus 2.0 ml of the drug dilution medium. Six concentrations of

  test compound in a series of semi-logarithmic dilutions

  Based on this, three concentrations of the ddC positive control drug were tested. Each assay consisted of three cells for each concentration of test compound and six virus-infected cultures and six cell control cultures. On the third day after inoculation of the virus, drug toxicity to SC-1 cells was determined by microscopic examination of duplicate control culture stained with cells and drug. The remaining test cultures and control cultures were irradiated with ultraviolet light for 20 seconds and XC cells were added to each culture (5 × 10 5 cells / well in 2.5 ml of 10% EMEM medium). heat inactivated FBS). On the third day after irradiation with ultraviolet light, the cultures were fixed with formalin and stained with crystal violet. The plaques

  were counted using a dissecting microscope.

  The antiviral activity in the reduction of CAS-BR-M plaques was expressed in terms of reducing the average number of plaques counted in the virus-infected cultures treated with the drug, compared with the average number of plaques counted in the cultures. untreated controls, infected with the virus (percent compared to the control). The compound of the Example

10 had a DE50 dose of 1.1 μg / ml.

  (D) Activity against Simian Retrovirus SAIDS (SRV-2) A selective antiviral study against the virus - SAIDS (D / Washington) was performed according to a syncytial inhibition test on Raji cells. The drug was diluted in Iscove's complete medium and then ml of each dilution was added to the appropriate cells of a 96-well plate. Active growth phase Raji cells in an amount of 5 x 103 cells in 50 ul of Iscove's complete medium were then added to each cell. This was followed by the addition of 50 ul clarified supernatant liquor from SRV-2 / Raji cell culture. From ddC to

  been included in this trial as a positive control drug.

  Plates were incubated at 37C in a humidified atmosphere containing 5% CO 2. Syncytial cells were counted on the seventh day after infection. The toxicity of the drug was evaluated by comparing the viable cell numbers of the uninfected sample treated with the drug with the viability of the untreated and uninfected control. The compound of Example 10

  presented a DE50 value of 2.8 μg / ml.

  (E) Activity against Visna Maedi virus The antiviral activity against Visna Maedi virus strain WLC-1 (VMV) was determined by measuring the reduction of the specific immunohistochemical staining of the virus. Monolayers of sheep choroid plexus cells were infected with the VMV virus and were

  coated with serial dilutions of the test compounds.

  After incubation for five days, the monolayers were further incubated with specific antiserumns of

  viruses conjugated to horseradish peroxidase (HRP).

  Subsequent incubation of monolayers with a substrate

  HRP chromagene stains replication areas of the virus.

  These discrete foci were counted and the test compound concentration needed to reduce the number of foci to 50% of that of untreated controls

has been calculated.

  The compound of Example 13 had a DE50 value

0.2 g / ml.

Example 22

CYTOTOXIC ACTIVITY

  The compounds of Examples 5, 7 and 8 showed cytotoxic activity when tested against P388 mouse leukemia cell culture, as described by R. G. Alonquist and R. Vince in J. Med. Chem., 16, 1396 (1973). The ED 50 values (g / ml) obtained were as follows: EXAMPLE 5 Example 7 40 Example 8 3

2626,002

Claims (17)

  1. Compound of formula (I) x Z N // \ / HO-CH2 * / ZX N / Y I   wherein X is hydrogen, NRR1, SR, OR or halogen; Z is hydrogen, OR2 or NRR1; R, R1 and R2 may be the same or different and are selected from hydrogen, C1 to C4 alkyl and aryl groups;   and pharmaceutically acceptable derivatives thereof.   2. Compound according to claim 1, characterized in that Z represents H, OH or NH 2 in the formula (I).   3. Compound according to claim 1 or 2,   characterized in that Z represents NH2.   4. Compound according to any of   Claims 1 to 3, characterized in that X represents   hydrogen, a chloro radical, an NH 2, SH or OH group.   5. In accordance with any of the   Claims 1 to 4, characterized in that X represents   OH. 6. A compound according to any of   Claims 1 to 4, characterized in that X represents H or NH2.   7. (1α, 4α) -4- (6-chloro-9H-purin-9-yl) -2- cyclopenténylcarbinol;   (1a, 4a) -4- (6-hydroxy-9H-purin-9-yl) -2- cyciopenténylcarbinol;   (1a, 4a) -4- (6-amino-9H-purin-9-yl) -2-   cyclopenténylcarbinol; (1α, 4α) -4- (6-mercapto-9H-purin-9-yl) -2-cyclopentenylcarbinol;   (1α, 4α) -4- (2,6-diamino-9H-purin-9-yl) - 2-cyclopenténylcarbinol;   (1a, 4a) -4- (2-amino-6-chloro-9H-purine) yl) -2-cyclopentenylcarbinol or   (1a, 4a) -4- (2-amino-9H-purin-9-yl) -2-   cyclopentenylcarbinol according to claim 1.   8. (1a, 4a) -4- (2-amino-6-hydroxy-9H-purine)   9-yl) -2-cyclopentenylcarbinol according to claim 1.   9. Compound according to any of   Claims 1 to 8, characterized in that it is primarily   usually in the form of a racemic mixture.   10. A compound according to any of   claims 1 to 8, characterized in that it is essen-   actually consists of an optical isomer.   11. A compound according to any one of   Claims 1 to 8, characterized in that it is primarily   mainly composed of the D isomer. 12. Compound of formula (I) according to one   any of claims 1 to 11 or a phar-   of this compound, intended to be   used as an active therapeutic agent.   13. A compound of formula (I) as defined in   any of claims 1 to 11 or a derivative   pharmaceutically acceptable compound thereof for use in the preparation of a medicament for the treatment of a viral infection.   14. Pharmaceutical formulation, characterized in that it comprises a compound of formula (I) according to one of   any of claims 1 to 11 or a phar-   maceutically acceptable for this compound in combination with   a suitable pharmaceutically acceptable carrier.   15. Pharmaceutical formulation, characterized in that it comprises a compound of formula (I) below   any one of claims 1 to 11il or a salt   pharmaceutically acceptable compound thereof   with a suitable pharmaceutically acceptable carrier.   16. Pharmaceutical formulation according to claim 13, characterized in that it comprises in   besides another therapeutic agent.   17. Compound of formula (II) TO! y \ xNH2 Noh Z N NH   Wherein X is hydrogen, NRR1, SR, OR, halogen or protected forms thereof; Y represents OH or one of its protected forms; Z represents hydrogen, a group OR2, NRR1 or one of their protected forms; R, R1 and R2 may be the same or different and are selected from hydrogen and C1-C4 alkyl and aryl,   or pharmaceutically acceptable derivatives thereof.