Extracellular nucleotides such as adenosine triphosphate (ATP), uridine triphosphate (UTP) and uridine diphosphate (UDP) play a fundamental role in mediating a number of physiological functions including, for example a general role in the control of secretions such as the clearance of retained mucus secretions and stimulation of ciliary beat frequency and particularly a central role in the coordination of mucociliary clearance mechanisms in the lung. Molecular biological techniques have allowed the discovery of several families of membrane bound receptors for these highly charged molecules.

Thus, the P2X receptors are ligand-gated ion channels that are implicated in various neuromodulatory processes. The P2Y family of receptors are 7- transmembrane G-protein coupled receptors that bind both purine and pyrimidine nucleotides (Williams and Bhagwat, Ann. Rep. Med. Chem. 1996, 31,21-30).

The P2Y receptors have been further subdivided into 9 subtypes known as P2Y1 to P2Y8 and P2Y11 (Fisher, B. , Exp. Opin. Ther. Patents, 1999,9, 385-399 ; Yerxa, B. R. and Johnson, F. L., Drugs of the Future, 1999,24, 759-769). P2Y2 receptors have been implicated in the pathology of several disease states including lung diseases such as chronic obstructive pulmonary disease (which includes amongst others cystic fibrosis, chronic bronchitis and emphysema) and tear secretion, thrombosis, pain, cancer, sepsis and ischaemia-reperfusion injury.

P2Y2 receptors are found on the apical surface of airway epithelia and are believed to be the major coordinators of mucociliary clearance mechanisms in the lung. The continuous, cephalad movement of lower respiratory material is necessary for the clearance of inhaled pathogenic organisms or injurious

particles and is essential to maintain airways necessary for efficient gas exchange. The movement of airway secretions, along with accompanying lumenal cells and free foreign particles is accomplished by the actions of several cell types within the respiratory tract. Mucous is secreted by goblet cells and submucosal glands and forms a gel-like protective sheet within the lumen of the respiratory tract. The layer of mucus is propelled by the rhythmical, coordinated beat of the ciliated epithelial cells lining the airways from the terminal bronchi to the oropharynx and lining of the nose. The viscous mucous sheet would be immovable except that it floats on a much less viscous layer of fluid above the beating cilia. This periciliary fluid layer is maintained by the transport of ions (chloride and sodium) across the epithelium into the lumen of the airways followed by passive diffusion of water. Activation of P2Y2 by its presumed endogenous agonist, UTP, as well as by other nucleoside phosphates leads to increased mucociliary clearance presumably by increased chloride and water transport across the luminal surface (Mason, S. et al Br. J. Pharmacol., 1991,103, 1649-1656), increased cilia beat frequency (Drutz, D. et al, Drug Dev. Res. 1996,37, 185), increased mucin release (Lethem, M. et al, Am. J. Respir. Cell Mol. Biol., 1993,9, 315-322) and increased surfactant release (Gobran, L. et al, Am. J.

Physio., 1994,272, L187-196).

It has recently been discovered that the P2Y6 receptor, which selectively recognizes UDP as a potent ligand, also exists in airway tissue (International Patent Specification WO 99/09998). P2Y6 activation is also associated with chloride ion secretion and may play a role in coordination of mucociliary clearance mechanisms.

Cystic fibrosis (CF) is the most lethal genetic disease in caucasians in the U. S. A. , affecting approximately 1 in 2000 individuals (Fiel, S. B. et al, Semin. Respir. Crit. Care Med. , 1994,15, 349-355), with median survival age being 30 years. CF occurs due to mutations in the gene that codes for the CF Transmembrane Conductance Regulator (CFTR) protein (Rommens, J. M. et al, Science, 1989,245, 1059-1080). These mutations account for the

abnormalities in sodium, chloride and water transport across epithelial cells resulting in dehydration and thickening of the mucus layer above the affected cells. The inability of CF patients to clear this thickened mucus and potential pathogens leads to chronic lung infection, progressive lung disease and impaired lung function, with lung infection accounting for 90% of deaths from CF.

New therapeutic approaches to the treatment of CF are required and one approach is the provision of agents that correct the underlying ion transport defects via physiological mechanisms that do not rely on the CFTR in order to normalize airway secretions, leading to improved mucociliary clearance and prevention of lung infections and damage. In this regard P2Y2 and P2Y6 receptor agonists may enhance mucociliary clearance by the mechanisms just mentioned. UTP, UDP and ATP have been demonstrated to activate chloride channel function, leading to hydration of lung mucin secretions (U. S.

Patent No. 5,292, 498 and International Patent Specification W099/09998) and increased ciliary beat frequency (Boucher, R. et al, Adenosine and Adenine Nucleotides : From Molecular Biology to Integrative Physiology, 525- 532, Belardinelli, L. and Pelleg, A. , Eds, Alumwer Academic Publishers, Boston, 1995) in the lung epithelial cells of CF patients. A combination of aerosolised UTP and amiloride has also been reported to improve mucociliary clearance from the peripheral airways of the lungs of CF patients to near normal levels (Bennett, W. D. et al, AM. J. Res. Critical Care Med.

1996,153, 1796-1802).

Additionally a series of dinucleotides have also been disclosed as useful in the treatment of airway diseases including CF (U. S. Patent No. 5,635, 160), chronic brochitis (International Patent Specifications WO 98/34942 and WO 99/61012) and sinusitis (U. S. Patent No. 5,972, 904).

Abnormal tear secretion can lead to dry eye disease, a general term for indications produced by abnormalities of the precorneal tear film characterised by a decrease in tear production or an increase in tear film

evaporation, in combination with the resulting ocular surface disease. Current treatment of dry eye disease is limited to the use of artificial tears which is a short lived solution. Tear secretion may be stimulated from lacrimal accessory tissues via P2Y2 and/or P2Y4 purinergic receptor mediated mechanisms similar to those that hydrate airway epithelia, and agonists of these receptors may be useful in the treatment of dry eye disease.

P2Y2 and P2Y4 receptors also play a role in the control of glucose uptake into mammalian cardiac mycocytes (see International Patent Specification WO 99/43326). Use of agonists of these receptors to enhance glucose uptake may be used to minimize ischemic cardiac damage, such as that attributable to angina, myocardial infarction, cardiac arrhythmia, coronary artery disease, diabetes mellitus and cardiac ischemia attributable to shock, stress or exertion.

Since UTP, UDP and related dinucleotides are subject to rapid degradation in vivo their actions are likely to be short lived. Consequently there is a need for alternative long acting P2Y agonists. We have now found such a group of compounds which are potent longer acting P2Y agonists, particularly P2Y2, P2Y4 and/or P2Y6 agonists. The compounds are of use in medicine, for example in the treatment of diseases and disorders involving abnormal secretory mechanisms such as inadequate functioning of the mucociliary clearance mechanisms or abnormal tear secretion or in the treatment of diseases involving inappropriate cellular glucose uptake.

Thus according to one aspect of the invention we provide a compound of formula (1):

wherein: G is a hydrogen atom or an optionally substituted aliphatic, heteroaliphatic, cycloaliphatic, heterocycloaliphatic, polycycloaliphatic, heteropolycyclo- aliphatic, aromatic or heteroaromatic group or a group of formula : in which Y and Z is each independently a hydrogen or halogen atom or a hydroxyl (-OH), alkoxy, azido (-N3), amino (-NH2), alkylamino or dialkylamino group, b represents the point of attachment to the remainder of the compound of formula (1) and B is an optionally substituted carbon-linked bicyclic heteroaromatic group: G'is a group of formula : in which B'is an optionally substituted carbon-linked bicyclic heteroaromatic group, Z'and Y'is each an atom or group as previously defined for Z and b is as previously defined; n is zero, or the integer 1 or 2; m is zero or the integer 1 or 2; and the salts, solvates, hydrates and N-oxides thereof for use in modulating P2Y receptor activity.

The compounds of formula (1) are potent agonists of P2Y receptors, particularly P2Y2, P2Y6 and/or P2Y4 receptors. The ability of the compounds

to act in this way may be simply determined by employing tests such as those described hereinafter.

The compounds according to the invention are generally of use in modulating secretory processes and in particular are of use in the prophylaxis and treatment of lung diseases or disorders such as those involving inadequate functioning of the mucociliary clearance mechanisms such as chronic obstructive pulmonary disease and the invention extends to such a use and to the use of the compounds for the manufacture of a medicament for treating such diseases or disorders.

Diseases or disorders of this type include chronic bronchitis, Primary Ciliary Dyskinesia and cystic fibrosis. Additionally compounds according to the invention may be used in the prevention of pneumonia due to immobility.

Furthermore, due to their general ability to increase hydration, clear retained mucus secretions and stimulate ciliary beat frequency, the compounds according to the invention are also useful in the treatment of sinusitis, otitis media, post-operative mucous retention, nasolacrimal duct obstructions, female infertility or irritation caused by vaginal dryness and nasolacrimal duct obstructions. In addition the compounds according to the present invention are useful for treating dry eye and retinal detachment. The compounds may also be of use in the control of glucose uptake in mammalian cardiac mycocytes.

For the prophylaxis or treatment of disease the compounds according to the invention may be administered as pharmaceutical compositions, and according to a further aspect of the invention we provide a pharmaceutical composition which comprises a compound of formula (1) together with one or more pharmaceutically acceptable carriers, excipients or diluents.

Pharmaceutical compositions according to the invention may take a form suitable for oral, buccal, parenteral, nasal, topical, vaginal or rectal administration, or a form suitable for administration by inhalation or insufflation.

For oral administration, the pharmaceutical compositions may take the form of, for example, tablets, lozenges or capsules prepared by conventional means with pharmaceutical acceptable excipients such as binding agents (e. g. pregelatinised maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose) ; fillers (e. g. lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e. g. magnesium stearate, talc or silica) ; disintegrants (e. g. potato starch or sodium glycollate) ; or wetting agents (e. g. sodium lauryl sulphate). The tablets may be coated by methods well known in the art. Liquid preparations for oral administration may take the form of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may be prepared by conventional means with pharmaceutical acceptable additives such as suspending agents, emulsifying agents, non-aqueous vehicles and preservatives. The preparations may also contain buffer salts, flavouring, colouring and sweetening agents as appropriate.

Preparations for oral administration may be suitably formulated to give controlled release of the active compound.

For buccal administration the compositions may take the form of tablets or lozenges formulated in conventional manner.

The compounds for formula (1) may be formulated for parenteral administration by injection e. g. by bolus injection or infusion. Formulations for injection may be presented in unit dosage form, e. g. in glass ampoule or multi dose containers, e. g. glass vials. The compositions for injection may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilising, preserving and/or dispersing agents. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e. g. sterile pyrogen-free water, before use.

For particle mediated administration the compounds of formula (1) may be coated on particles such as microscopic gold particles.

In addition to the formulations described above, the compounds of formula (1) may also be formulated as a depot preparation. Such long acting formulations may be administered by implantation or by intramuscular injection.

For nasal administration or administration by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation for pressurised packs or a nebuliser, with the use of suitable propellant, e. g. dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas or mixture of gases.

For topical administration the compounds of formula (1) may be delivered in the form of a liquid or gel suspension in the form of drops, spray or gel. These formulations may be prepared by mixing the active ingredient with a suitable physiologically compatible vehicle. Such vehicles include for example saline solution, water soluble polyethers such as polyethylene glycol, polyvinyl such as polyvinyl alcohol, cellulose derivatives such as methylcellulose, petroleum derivatives such as mineral oil and white petroleum, animal fats such as lanolin, polymers of acrylic acid such as carboxypolymethylene gel, vegetable fats such as peanut oil and polysaccharides such as dextrans.

For vaginal or rectal administration the compounds of formula (1) may be formulated as a suppository. These formulations may be prepared by mixing the active ingredient with a suitable non-irritating excipient which is a solid at room temperature but liquid at the body temperature. Such materials include for example cocoa butter and polyethylene glycols.

The compositions may, if desired, be presented in a pack or dispenser device which may contain one or more unit dosage forms containing the active ingredient. The pack or dispensing device may be accompanied by instructions for administration.

The quantity of a compound of the invention required for the prophylaxis or treatment of a particular condition will vary depending on the compound chosen, and the condition of the patient to be treated. In general, however, daily dosages may range from around 100ng/kg to 100mg/kg e. g. around 0. 01mg/kg to 40mg/kg body weight for oral or buccal administration, from around 10ng/kg to 50mg/kg body weight for parenteral administration and around 0. 05mg to around 1000mg e. g. around 0. 5mg to around 1000mg for nasal administration or administration by inhalation or insufflation.

Particular compounds of formula (1) form a further aspect of the invention and in a further aspect we therefore provide a compound of formula (1 c): wherein: G is a hydrogen atom or an optionally substituted aliphatic, heteroaliphatic, cycloaliphatic, heterocycloaliphatic, polycycloaliphatic, heteropolycyclo- aliphatic, aromatic or heteroaromatic group or a group of formula : in which Y and Z is each independently a hydrogen or halogen atom or a hydroxyl (-OH), alkoxy, azido (-N3), amino (-NH2), alkylamino or dialkylamino group, b represents the point of attachment to the remainder of the compound of formula (1) and B is an optionally substituted carbon-linked bicyclic heteroaromatic group; G'is a group of formula :

in which B'is an optionally substituted carbon-linked bicyclic heteroaromatic group, Z'and Y'is each an atom or group as previously defined for Z and b is as previously defined; n is zero, or the integer 1 or 2; m is zero or the integer 1 or 2; provided that: 1) when n and m is each zero, G is a hydrogen atom and G'is a group of formula (1b) in which Y'and Z'is each a hydroxyl (-OH) group then B'is other than a 7H-pyrazolo [4,3-d] pyrimidine-7-one-3-yl, 7-amino-1 H- pyrazol [4,3-d] pyrimidin-3-yl, 4H-pyrrolo [3,2-d] pyrimidin-4-one-7-yl or 4- amino-4H-pyrrolo [3,2-d] pyrimidin-7-yl group; 2) when one of n and m is the integer 1 and the other is zero, G is a hydrogen atom and G'is a group of formula (1 b) in which Y'and Z'is each a hydroxyl (-OH) group then B'is other than a 7H-pyrazolo [4,3- d] pyrimidine-7-one-3-yl, 5-amino-7H-pyrazolo [4,3-d] pyrimidine-7-one-3-yl, 7-amino-1 H-pyrazolo [4, 3-d] pyrimidin-3-yl, 2-amino-4H-pyrrolo [3,2- d] pyrimidin-4-one-7-yl, 4H-pyrrolo [3,2-d] pyrimidin-4-one-7-yl, 2-amino-4H- pyrrolo [3,2-d] pyrimidin-4-one-7-yl, 4-aminothieno [3,2-d] pyrimidin-7-yl, 4- amino-4H-pyrrolo [3,2-d] pyrimidin-7-yl or 4-amino-5H-pyrrolo [3,2- d] pyrimidin-7-yl group; 3) when n and m is each zero, G'is a group of formula (1 b) in which Y'and Z'is each a hydroxyl (-OH) group and B'is a 7-amino-1 H-pyrazolo [4,3- d] pyrimidin-3-yl group and G is a group of formula (1a) in which Y'and Z' is each a hydroxyl (-OH) group then B is other than a 7-amino-1H- pyrazol [4,3-d] pyrimidin-3-yl group;

and the salts, solvates, hydrates and N-oxides thereof.

It will be appreciated that compound of formulae (1), (1a), (1b), and (1c) may have one or more chiral centres, and exist as enantiomers or diastereomers (for example as indicated by wiggly lines in formula (1a)). The invention is understood to extend to all such enantiomers, diastereomers and mixtures thereof, including racemates. In addition, compounds of formula (1), (1a), (1b) and (1c) may exist as tautomers, for example keto (CH2C=O)-enol (CH=CHOH) tautomers. Formulae (1), (1 a), (1 b) and (1 c) and the formulae hereinafter are intended to represent all individual isomers, tautomers and mixtures thereof unless stated or shown otherwise.

The following general terms as used herein have the stated meaning unless specifically described otherwise.

As used herein the term"alkyl"whether present as a group or part of a group includes straight or branched Cl-alkyl groups, for example C14alkyl groups such as methyl, ethyl, n-propyl, i-propyl or t-butyl groups. Similarly, the terms "alkenyl"or"alkynyl"are intended to mean straight or branched C26alkenyl or C26alkynyl groups such as C2-4alkenyl or C2-4alkynyl groups. Optional substituents which may be present on these groups include those optional substituents mentioned hereinafter in relation to G when G is an optionally substituted aliphatic group.

The term halogen is intended to include fluorine, chlorine, bromine or iodine atoms.

The term"haloalkyl"is intended to include those alkyl groups just mentioned sustituted by one, two or three of the halogen atoms just described. Particular examples of such groups include-CF3,-CC13,-CHF2,-CHCt2,-CH2F and- CH2CI groups.

The term"alkoxy"as used herein is intended to include straight or branched C16alkoxy e. g. C14alkoxy such as methoxy, ethoxy, n-propoxy, i-propoxy and t-butoxy."Haloalkoxy"as used herein includes any of these alkoxy groups substituted by one, two or three halogen atoms as described above.

Particular examples include-OCF3,-OCCI3,-OCHF2,-OCHCI2,-OCH2F and -OCH2CI groups.

As used herein the term"alkylthio"is intended to include straight or branched C16alkylthio, e. g. C14alkylthio such as methylthio or ethylthio.

As used herein the term"alkylamino or dialkylamino"is intended to include the groups -NHR1 and -N(R1)2 [where R1 is an optionally substituted straight or branched alkyl group]. Where two R'groups are present these may be the same or different. In addition where two R'groups are present these may be joined together with the N atom to which they are attached to form an optionally substituted heterocycloalkyl group which may contain a further heteroatom or heteroatom containing group such as an-O-or-S-atom or- N (R')- group. Particular examples of such optionally substituted heterocycloalkyl groups include optionally substituted pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl and N'-C16alkyl-piperazinyl groups. The optional substituents which may be present on such heterocycloalkyl groups include those optional substituents as described hereinafter in relation to aliphatic groups.

When the group G is present in compounds of formula (1) as an optionally substituted aliphatic group it may be an optionally substituted Ci. ioa) iphatic chain. Particular examples include optionally substituted straight or branched chain C16alkylene, C26alkenylene, or C26alkynylene groups.

Particular examples of aliphatic groups represented by G include optionally substituted-CH3,-CH2CH3,-CH (CH3) CH3,- (CH2) 2CH3,- (CH2) 3CH3,- CH (CH3) (CH2) 2CH3, -CH2CH (CH3) CH3, -C (CH3) 2CH3,-CH2C (CH3) 2CH3,- (CH2) 2CH (CH3) CH3, -CH (CH3) CH2CH3, -CH (CH3) CH2CH (CH3) 2,-CH2CH

(CH3) CH2CH3,-(CH2) 2C (CH3) 3, -(CH2)4CH3, -(CH2)5CH3, -CHCH2, -CHCHCH3, -CH2CHCH2, -CHCHCH2CH3, -CH2CHCHCH3, -9CH2)2CHCH2, -CCH, - CCCH3, -CH2CCH, -CCCH2CH3, -CH2CCCH3, or -(CH2)2CCH2 groups.

Heteroaliphatic groups represented by the group G in the compounds of formula (1) include the aliphatic groups just described but with each additionally containing one, two, three or four heteroatoms or heteroatom-containing groups.

Particular heteroatoms or groups include atoms or groups L1 where L1 is a linker atom or group. Each L1 atom or group may interrupt the aliphatic group, or may be positioned at its terminal carbon atom to connect the group to an adjoining atom or group. Particular examples include optionally substituted -L1CH3, - CH2L1CH3, -L1CH2CH3, -CH2L1CH2CH3, -(CH2)2L1CH3, -(CH2)3L1CH3, -L1(CH2)3, -L1CH2CHCH2 and -(CH2)2L1CH2CH3 groups.

When L1 is present in heteroaliphatic groups as a linker atom or group it may be any divalent linking atom or group. Particular examples include-O-or-S- atoms or-C (O)-,-C (O) O-, -OC (O)-,-C (S) -,-S (O)-,-S (O) 2-, -N (R2)- [where R2 <BR> <BR> <BR> is a hydrogen atom or a straight or branched alkyl group], -N (R2) O-,-N (R2) N-, -CON(R2)-, -OC(O) N (R2)-,-CSN (R2)-,-N (R2) CO-,-N (R2) C (O) O-,-N (R2) CS-,- S (O) 2N (R2)-,-N (R2) S (O) 2-, -N (R2) CON (R2)-, -N(R2) CSN (R2)- or - N (R2) SO2N (R2)-groups. Where L'contains two R2 groups these may be the same or different.

The optional substituents which may be present on aliphatic or heteroaliphatic groups represented by G include one, two, three or more substituents where each substituent may be the same or different and is selected from halogen atoms, e. g. fluorine, chlorine, bromine or iodine atoms, or-OH,-C02H,-CO2R3 [where R3 is an optionally substituted straight or branched C16alkyl group], e. g.

-CO2CH3 or -CO2C (CH3) 3, -CONHR3, e. g.-CONHCH3,-CON (R3) 2, e. g.- CON (CH3) 2, -COR3, e. g.-COCH3, C1-6alkoxy, e. g. methoxy or ethoxy, halo1 <BR> <BR> <BR> 6alkoxy, e. g. trifluoromethoxy or difluoromethoxy, thiol (-SH) -S (O) R3, e. g.-<BR> <BR> <BR> <BR> S (O) CH3, -S (0) 2R3, e. g.-S (0) 2CH3, Ci-6alkylthio e. g. methylthio or ethylthio, amino, alkylamino, e. g.-NHCH3, dialkylamino, e. g.-N (CH3) 2 or optionally

substituted cycloaliphatic, heterocycloaliphatic, aromatic or heteroaromatic groups. Where two R3 groups are present in any of the above substituents these may be the same or different. Optionally substituted cycloaliphatic and heterocycloaliphatic groups include those optionally substituted cycloaliphatic and heterocycloaliphatic groups and optional substitutuents described hereinafter in relation to G, especially optionally substituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopentenyl, tetrahydrofuranyl, dihydrofuranyl and tetrahydropyranyl groups. Optionally substituted aromatic and heteroaromatic groups include those optionally substituted aromatic and heteroaromatic groups and optional substituents described hereinafter in relation to G, especially optionally substituted phenyl, thienyl, furanyl, pyridyl and pyrimidinyl groups.

Optionally substituted cycloaliphatic groups represented by the group G in compounds of the invention include optionally substituted C3_iocycloaliphatic groups. Particular examples include optionally substituted C3-locycloalkyl, e. g.

C37cycloalkyl or C310cycloalkenyl, e. g C3-7cycloalkenyl groups.

Optionally substituted heterocycloaliphatic group represented by the group G include optionally substituted C3-loheterocycloaliphatic group. Particular examples include optionally substituted C310heterocycloalkyl, e. g. C3- 7heterocycloalkyl or C3. loheterocycloalkenyl, e. g. C37heterocycloalkenyl groups, each of said groups containing one, two, three or four heteroatoms or heteroatom containing groups L where L2 is an atom or group as previously defined for L'.

Optionally substituted polycycloaliphatic groups represented by the group G include optionally substituted C7-lobi-or tricycloalkyl or C7-lobi-or tricycloalkenyf groups. Optionally substituted heteropolycycloaliphatic groups represented by the group G include optionally substituted C7. lobi- or tricycloalkyl or C7-lobi-or tri-cycloalkenyl groups containing one, two, three, four or more 2 atoms or groups.

Particular examples of cycloaliphatic, polycycloaliphatic, heterocycloaliphatic and heteropolycycloaliphatic groups represented by the group G include optionally substituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, 2-cyclobuten-1-yl, 2-cyclopenten-1-yl, 3-cyclopenten-1-yl, adamantyl, norbornyl, norbornenyl, dihydrofuranyl, tetrahydrofuranyl, tetrahydropyranyl, dihydrothiophenyl, tetrahydrothiophenyl, pyrroline, e. g. 2- or 3-pyrrolinyl, pyrrolidinyl, pyrrolidinone, oxazolidinyl, oxazolidinone, dioxolanyl, e. g. 1, 3-dioxolanyl, imidazolinyl, e. g. 2-imidazolinyl, imidazolidinyl, pyrazolinyl, e. g. 2-pyrazolinyl, pyrazolidinyl, 5,6-dihydro-2 (1 H)-pyrazinone, tetrahydropyrimidinyl, thiazolinyl, thiazolidinyl, pyranyl, e. g. 2-or 4-pyranyl, piperidinyl, homopiperidinyl, heptamethyleneiminyl, piperidinone, 1,4- dioxanyl, morpholinyl, morpholinone, 1, 4-dithianyl, thiomorpholinyl, piperazinyl, homopiperazinyl, 1,3, 5-trithianyl, oxazinyl, e. g. 2H-1,3-, 6H-1,3-, 6H-1,2-, 2H-1, 2- or 4H-1, 4-oxazinyl, 1,2, 5-oxathiazinyl, isoxazinyl, e. g. o-or p-isoxazinyl, oxathiazinyl, e. g. 1,2, 5 or 1,2, 6-oxathiazinyl, 1,3, 5-oxadiazinyl, dihydroisothiazolyl, dihydroisothiazole 1, 1-dioxide, e. g. 2,3- dihydroisothiazole 1,1-dioxide, dihydropyrazinyl and tetrahydropyrazinyl groups.

The optional substituents which may be present on the cycloaliphatic, polycycloaliphatic, heterocycloaliphatic or polyheterocycloaliphatic groups represented by the group G include one, two, three or more substituents selected from halogen atoms, or C16alkyl, e. g. methyl or ethyl, haloC16alkyl, e. g. halomethyl or haloethyl such as difluoromethyl or trifluoromethyl, optionally substituted by hydroxyl, e. g. -C (OH) (CF3) 2, C16alkoxy, e. g. methoxy or ethoxy, haloC16alkoxy, eg. halomethoxy or haloethoxy such as difluoromethoxy or trifluoromethoxy, thiol, C16alkylthiol, e. g. methylthiol or ethylthiol, carbonyl (=O), thiocarbonyl (=S), imino (=NR4a) [where R4a is an- OH group or a C16alkyl group], or -(Alk1)vR5 groups in which Alk'is a straight or branched C13alkylene chain, v is zero or the integer 1 and R5 is a C3- 8cycloalkyl,-OH,-SH,-N (R6) (R7) [in which R6 and R7 is each independently selected from a hydrogen atom or an optionally substituted alkyl or C3- 8cycloalkyl group],-OR6,-SR6,-CN,-N02,-C02R6,-SOR6,-S02R6,-SOsRs,-

OC02R6,-C (O) R6,-OC (O) R6,-C (S) R6,-C (O) N (R6) (R7),-OC (O) N (R6) (R'),- N (R6) C (O) R 7,-C (S) N (R6) (R7)-N (R6) C (S) R7, -SO2N(R6)(R7), -N(R6)SO2R7, - N (R6) C (O) N (R7)(R8) [where R8 is as defined for R6], -N(R6) C (S) N (R (R$),- N (R6)SO2N(R7)(R8) or an optionally substituted aromatic or heteroaromatic group.

Particular examples of Alk'chains include-CH2-,-CH2CH2-,-CH2CH2CH2- and-CH (CH3) CH2- chain.

When R5, R6, R7 and/or R8 is present as a C3-8cycloalkyl groups it may be for example a cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl group. Optional substituents which may be present on such groups include for example one, two or three substituents which may be the same or different selected from halogen atoms, for example fluorine, chlorine, bromine or iodine atoms, or hydroxy or C16alkoxy, e. g. methoxy, ethoxy or i-propoxy groups.

When the groups R6 and R7 or R7 and R8 are both alkyl groups these groups may be joined, together with the N atom to which they are attached, to form a heterocyclic ring. Such heterocyclic rings may be optionally interrupted by a further heteroatom or heteroatom containing group selected from-O-,-S-,- N (R7)-,-C (O)-or-C (S)-groups. Particular examples of such heterocyclic rings include piperidinyl, pyrazolidinyl, morpholinyl, thiomorpholinyl, pyrrolidinyl, imidazolidinyl and piperazinyl rings.

Additionally, when the group G is a heterocycloaliphatic or polyheterocycloaliphatic group containing one or more nitrogen atoms each nitrogen atom may be optionally substituted by a group -(L3) p (Alk2) qR9 in which L3 is a-C (O)-,-C (O) O-,-C (S) -,-S (O) 2-, -CON (R6)- or -SO2N(R6)-; p is zero or the integer 1; Alk2 is an optionally substituted aliphatic or heteroaliphatic chain; q is zero or the integer 1; and R9 is a hydrogen atom or an optionally substituted cycloaliphatic, heterocycloaliphatic, polycycloaliphatic, heteropolycycloaliphatic, aromatic or heteroaromatic group.

When Alk2 is present as an aliphatic or heteroaliphatic chain it may be for example any divalent chain corresponding to the above-mentioned aliphatic or heteroaliphatic groups described for G, where a terminal hydrogen atom is replaced by a bond.

Aromatic or heteroaromatic groups represented by R5 and/or R9 include those aromatic and heteroaromatic groups as mentioned hereinafter in relation to the group G. Optional substituents on these groups include those substituents as described hereinafter for those aromatic and heteroaromatic groups represented by G.

Cycloaliphatic, heterocycloaliphatic, polycycloaliphatic or heteropolycyclo- aliphatic groups represented by R9 include those groups as described hereinbefore for the group G. Optional substituents which may be present on these groups include those described in relation to G when G is a cycloaliphatic, heterocycloaliphatic, polycycloaliphatic or heteropolycycloaliphatic group.

Optionally substituted aromatic groups represented by the group G include for example monocyclic or bicyclic fused ring C612aromatic groups, such as phenyl, 1-or 2-napthyl, 1-or 2-tetrahydronapthyl, indanyl or indenyl groups.

Heteroaromatic groups represented by the group G include for example Ci- gheteroaromatic groups containing for example one, two, three or four heteroatoms selected from oxygen, sulphur or nitrogen atoms. In general, the heteroaromatic groups may be for example monocyclic or bicyclic fused ring heteroaromatic groups. Monocyclic heteroaromatic groups include for example five-or six-membered heteroaromatic groups containing one, two, three or four heteroatoms selected from oxygen, sulphur or nitrogen atoms.

Bicyclic heteroaromatic groups include for example eight-to thirteen- membered fused ring heteroaromatic groups containing one, two or more heteroatoms selected from oxygen, sulphur or nitrogen atoms.

Particular examples of heteroaromatic groups of these types include pyrrolyl, furyl, imidazolyl, N-C16alkylimidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, 1,2, 3-triazolyl, 1,2, 4-triazolyl, 1,2, 3-oxadiazolyl, 1,2, 5- oxadiazolyl, 1,3, 4-oxadiazolyl, 1,3, 4-thiadiazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, 1,3, 5-triazinyl, 1,2, 4-triazinyl, 1,2, 3-triazinyl, benzofuryl, [2, 3-dihydro] benzofuryl, benzothienyl, [2, 3-dihydro] benzothienyl, benzotriazolyl, indolyl, indolinyl, indazolinyl, benzimidazolyl, imidazo [1,2- a] pyridyl, benzothiazolyl, benzoxazolyl, benzisoxazolyl, benzopyranyl, [3,4- dihydro] benzopyranyl, quinazolinyl, quinoxalinyl, naphthyridinyl, mimidazo[1, 5- a] pyridinyl, imidazo [1,5-a] pyrazinyl, imidazo [1,5-c] pyrimidinyl, pyrido [3,4- b] pyridyl, pyrido [3,2-b] pyridyl, pyrido [4,3-b] pyridyl, quinolinyl, isoquinolinyl, phthalazinyl, tetrazolyl, 5,6, 7, 8-tetrahydroquinolinyl, 5,6, 7,8- tetrahydroisoquinolinyl, imidyl, e. g. succinimidyl, phthalimidyl or naphthalimidyl such as 1, 8-naphthalimidyl, pyrazolo [4,3-d] pyrimidinyl, furo [3,2-d] pyrimidinyl, thieno [3,2-d] pyrimidinyl, pyrrolo [3,2-d] pyrimidinyl, pyrazol [3,2-b] pyridinyl, furo [3,2-b] pyridinyl, thieno [3,2-b] pyridinyl, pyrrolo [3,2-b] pyridinyl, thiazolo [3, 2-a] pyyridinyl, pyrido [1, 2-a] pyrimidinyl, tetrahydroimidazo [1,2-a] pyrimidinyl and dihydroimidazo [1,2-a] pyrimidinyl groups.

Optional substituents which may be present on aromatic or heteroaromatic groups represented by the group G include one, two, three or more substituents, each selected from an atom or group Rlo in which Rlo is Rloa or -Alk3 (R10a) r, where Rloa is a halogen atom, or an amino (-NH2), substituted amino, nitro, cyano, amidino, hydroxyl (-OH), substituted hydroxyl, formyl, carboxyl (-C02H), esterified carboxyl, thiol (-SH), substituted thiol,-COR" [where R"is an-Alk3 (R'oa) r, aryl or heteroaryl group], -CSR11, -SO3H, - <BR> <BR> <BR> SOR",-SO2R",-SO3R",-S02NH2,-S02NHR",-S02N (R11) 2,-CONH2,-<BR> <BR> <BR> <BR> <BR> <BR> CSNH2,-CONHR",-CSNHR",-CON (R") 2, -CSN (R11) 2, -N (R12) SO2R" [where R12 is a hydrogen atom or a straight or branched alkyl group], - <BR> <BR> <BR> N (S02R") 2, -N (R12) S02NH2,-N (R12) S02NHR",-N (R'2) S02N (R11) 2,-<BR> <BR> <BR> <BR> <BR> <BR> N (R12) COR",-N (R12) CONH2, -N (R12) CONHR1 1,-N (R12) CON (R11)2, -

N (R'2) CSNH2, -N (R'2) CSNHR",-N (R12) CSN (R'1) 2,-N (R'2) CSR",- N (R12) C (O) OR11, -SO2NHeT1 [where-NHet'is an optionally substituted C5- 7cyclicamino group optionally containing one or more other -O- or -S- atoms or-N (R12)-, -C(O)- or -C(S)- groups], -CONHet1, -CSNHet1, = N (R12)SO2NHeT1, -N(R12)CONHet1, -N(R12)CSNHet1, -SO2N(R12) Het [where- <BR> <BR> <BR> Het is as previously defined], -Het,-CON (R12) Het, -CSN (R12) Het, -<BR> <BR> <BR> <BR> N (R) Het, -N (R12) CSN (R12)Het, -N(R12)SO2N(R12)Het, aryl or heteroaryl groups; Alk3 is a straight or branched C1-6alkylene, C26alkenylene or C26alkynylene chain, optionally interrupted by one, two or three-O-or-S- <BR> <BR> <BR> atoms or-S (O)n- [where n is an integer 1 or 2] or-N (R12)- e. g. -N (CH3)- groups; and r is zero or the integer 1,2, or 3. It will be appreciated that when two R11 or R12 groups are present in one of the above substituents the R" and R12 groups may be the same or different.

When in the group-Alk3 (R10a)m r is an integer 1,2 or 3, it is to be understood that the substituent or substituents Rloa may be present on any suitable carbon atom in-Alk3. Where more than one R10a substituent is present these may be the same or different and may be present on the same or different atom in- Alk3. Clearly, when r is zero and no substituent Rloa is present the alkylen, alkenylene or alkynylene chain represented by Alk3 becomes an alkyl, alkenyl or alkynyl group.

When R10a is a substituted amino group it may be for example a group -NHR11 [where R11 is as defined above] or a group-N (R11) 2 wherein each R"group is the same or different.

When Rloa is a halogen atom it may be for example a fluorine, chlorine, bromine, or iodine atom.

When Rloa is a substituted hydroxyl or substituted thiol group it may be for example a group -OR11 or a -SR12 or -SC (=NH) NH2 group respectively.

Esterified carboxyl groups represented by the group Rloa include groups of formula-CO2Alk4 wherein Alk4 is a straight or branched, optionally substituted C1-8alkyl group such as a methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl or t-butyl group; a C6-12arylC1-8alkyl group such as an optionally substituted benzyl, phenylethyl, phenylpropyl, 1-naphthylmethyl or 2-naphthylmethyl group; a C6-12aryl group such as an optionally substituted phenyl, 1-naphthyl or 2- naphthyl group; a C6-12aryloxyC1-8alkyl group such as an optionally substituted phenyloxymethyl, phenyloxyethyl, 1-naphthyloxymethyl, or oxymethyl group; an optionally substituted C1-8alkanoyloxyC1-8alkyl group, such as a pivaloyloxymethyl, propionyloxyethyl or propionyloxypropyl group; or a Ce- i2aroyioxyd-8aikyi group such as an optionally substituted benzoyloxyethyl or benzoyloxypropyl group. Optional substituents present on the Alk4 group include R10aatoms and groups as described above.

When Alk3 is present in or as a substituent it may be for example a methylene, ethylene, n-propylene, i-propylene, n-butylene, i-butylene, s-butylene, t- butylen, ethenylene, 1-propenylene, 2-propenylene, 1-butenylene, 2- butenylene, 3-butenylene, ethynylene, 1-propynylene, 2-propynylene, 1- butynylene, 2-butynylene or 3-butynylene chain, optionally interrupted by one, two, or three-O-or-S-, atoms or-S (O)-,-S (O) 2-or-N (R12)-, e. g.-N (CH3)- groups.

Aryl or heteroaryl groups represented by the groups Rloa or R"include mono- or bicyclic optionally substituted C6-12 aromatic or Cl-9 heteroaromatic groups as described above for the group G. The aromatic and heteroaromatic groups may be attached to the group G in compounds of formula (1) by any carbon or hetero e. g. nitrogen atom as appropriate.

When-NHet'forms part of a substituent R10 each may be for example an optionally substituted pyrrolidinyl, pyrazolidinyl, piperazinyl, morpholinyl, thiomorpholinyl, piperidinyl or thiazolidinyl group. Optional substituents which may be present on-NHet1 include those substituents described above when G is a heterocycloaliphatic group.

Particularly useful atoms or groups represented by R10 include fluorine, chlorine, bromine or iodine atoms, or C16alkyl, e. g. methyl, ethyl, n-propyl, i-propyl, n- butyl or t-butyl, optionally substituted phenyl, pyridyl, pyrimidinyl, pyrrolyl, furyl, thiazolyl, or thienyl, C16hydroxyalkyl, e. g. hydroxymethyl or hydroxyethyl, carboxyCl-6alkyl, e. g. carboxyethyl, C1-6alkylthio e. g. methylthio or ethylthio, carboxyC16alkylthio, e. g. carboxymethylthio, 2-carboxyethylthio or 3-carboxy- propylthio, Ci-6alkoxy, e. g. methoxy or ethoxy, hydroxyC16alkoxy, e. g. 2- hydroxyethoxy, optionally substituted phenoxy, pyridyloxy, thiazolyoxy, phenylthio or pyridylthio, C3-7cycloalkyl, e. g. cyclobutyl, cyclopentyl, C5- 7cycloalkoxy, e. g. cyclopentyloxy, haloC1-6alkyl, e. g. trifluoromethyl, halo1 6alkoxy, e. g. trifluoromethoxy, C1-6alkylamino, e. g. methylamino or ethylamino, amino (-NH2), aminoC16alkyl, e. g. aminomethyl or aminoethyl, C1-6dialkylamino, e. g. dimethylamino or diethylamino, C1-6alkylaminoC1-6alkyl, e. g. ethylaminoethyl, C1-6dialkylaminoC1-6alkyl, e. g. diethylaminoethyl, aminoCi- 6alkoxy, e. g. aminoethoxy, C16alkylaminoC16alkoxy, e. g. methylaminoethoxy, C16dialkylaminoC16alkoxy, e. g. dimethylaminoethoxy, diethylaminoethoxy, diisopropylaminoethoxy, or dimethylaminopropoxy, imido, such as phthalimido or naphthalimido, e. g. 1, 8-naphthalimido, nitro, cyano, amidino, hydroxyl (-OH), formyl [HC (O)-], carboxyl (-C02H),-CO2AIk4 [where Alk4is as defined above], Ci- 6 alkanol e. g. acetyl, optionally substituted benzoyl, thiol (-SH), thioC1-6alkyl, e. g. thiomethyl or thioethyl,-SC (=NH) NH2, sulphonyl (-S03H), Ci- 6alkylsulphonyl, e. g. methylsulphonyl, aminosulphonyl (-S02NH2), Ci- 6alkylaminosulphonyl, e. g. methylaminosulphonyl or ethylaminosulphonyl, C1 6dialkylaminosulphonyl, e. g. dimethylaminosulphonyl or diethylaminosulphonyl, phenylaminosulphonyl, carboxamido (-CON2), C1-6alkylaminocarbonyl, e. g. methylaminocarbonyl or ethylaminocarbonyl, C1-6dialkylaminocarbonyl, e. g. <BR> <BR> <BR> dimethylaminocarbonyl or diethylaminocarbonyl, aminoCi-alkylaminocarbonyl, e. g. aminoethylaminocarbonyl, C1-6dialkylaminoC1-6alkylaminocarbonyl, e. g. diethylaminoethylaminocarbonyl, aminocarbonylamino, C1-6alkylamino- carbonylamino, e. g. methylaminocarbonylamino or ethylaminocarbonylamino, C1-6dialkylaminocarbonylamino, e. g. dimethylaminocarbonylamino or diethyl- aminocarbonylamino, C1-6alkylaminocabonylC1-6alkylamino, e. g. methylamino-

carbonylmethylamino, aminothiocarbonylamino, C16alkylaminothiocarbonyl- amino, e. g. methylaminothiocarbonylamino or ethylaminothiocarbonylamino, Ci- 6dialkylaminothiocarbonylamino, e. g. dimethylaminothiocarbonylamino or diethylaminothiocarbonylamino, C16alkylaminothiocarbonylC16alkylamino, e. g. ethylaminothiocarbonylmethylamino,-CONHC (=NH) NH2, C16alkylsulphonyl- amino, e. g. methylsulphonylamino or ethylsulphonylamino, C16dialkyl- sulphonylamino, e. g. dimethylsulphonylamino or diethylsulphonylamino, optionally substituted phenylsulphonylamino, aminosulphonylamino (- NHS02NH2), Ci_6alkylaminosulphonylamino, e. g. methylaminosulphonylamino or ethylaminosulphonylamino, C16dialkylaminosulphonylamino, e. g. dimethyl- aminosulphonylamino or diethylaminosulphonylamino, optionally substituted morpholinesulphonylamino or morpholinesulphonylCl-6alkylamino, optionally substituted phenylaminosulphonylamino, C16alkanoylamino, e. g. acetylamino, aminoC16alkanoylamino e. g. aminoacetylamino, C16dialkylaminoC16alkanoyl- amino, e. g. dimethylaminoacetylamino, C16alkanoylaminoC16alkyl, e. g. acetylaminomethyl, C1-6alkanoylaminoC1-6alkylamino, e. g. acetamidoethyl- amino, C16alkoxycarbonylamino, e. g. methoxycarbonylamino, ethoxycarbonyl- amino or t-butoxycarbonylamino or optionally substituted benzyloxy, pyridylmethoxy, thiazolylmethoxy, benzyloxycarbonylamino, benzyloxy- carbonylaminoC16alkyl e. g. benzyloxycarbonylaminoethyl, benzothio, pyridyl- methylthio or thiazolylmethylthio groups.

Where desired, two Rlo substituents may be linked together to form a cyclic group such as a cyclic ether, e. g. a C16alkylenedioxy group such as methylenedioxy or ethylenedioxy.

It will be appreciated that where two or more Rlo substituents are present, these need not necessarily be the same atoms and/or groups. In general, the substituent (s) may be present at any available ring position in the aromatic or heteroaromatic group represented by the group G.

Optionally substituted carbon-linked bicyclic heteroaromatic groups represented by B and/or B'include for example eight to thirteen-membered

fused ring heteroaromatic groups containing one, two, three or four heteroatoms selected from oxygen sulphur or nitrogen atoms where in each case the heteroaromatic group is linked to the remainder of the compound of the invention via a carbon atom.

Particular examples of carbon-linked bicyclic heteroaromatic groups include benzofuryl, [2, 3-dihydro] benzofuryl, benzothienyl, [2,3-dihydro] benzothienyl, benzotriazolyl, indolyl, indolinyl, indazolinyl, benzimidazolyl, imidazo [1,2- a] pyridyl, benzothiazolyl, benzoxazolyl, benzisoxazolyl, benzopyranyl, [3,4- dihydro] benzopyranyl, quinazolinyl, quinoxalinyl, naphthyridinyl, pyrido [3,4- b] pyridyl, pyrido [3,2-b] pyridyl, pyrido [4,3-b] pyridyl, quinolinyl, isoquinolinyl, cinnolinyl, phthalazinyl ; 5,6, 7, 8-tetrahydroquinolinyl, 5,6, 7,8- tetrahydroisoquinolinyl"phthalimidyl, naphthalimidyl such as 1, 8- naphthalimidyl, pyrazol [4, 3-d] pyrimidinyl, furo [3, 2-d]pyrimidinyl, thieno [3,2- d] pyrimidinyl, pyrrolo [3,2-d] pyrimidinyl, pyrazol [3,2-b] pyridinyl, furo [3,2- b] pyridinyl, thieno [3,2-b] pyridinyl, pyrrolo [3, 2-b] pyridinyl, thiazolo [3,2- a] pyyridinyl, pyrido [1, 2-a] pyrimidinyl, tetrahydroimidazo [1,2-a] pyrimidinyl and dihydroimidazo [1, 2-a] pyrimidinyl groups.

The carbon-linked bicyclic heterocyclic group represented by B and/or B'may be optionally substituted on any available carbon or nitrogen atom. One, two, three or more of the same or different substituents (R13) may be present and each substituent may be selected from an atom or group-L4 (Alk5) tL5 (R14) U in which L4 and L5 which may be the same or different is each a covalent bond or a linker atom or group, t is zero or the integer 1, u is an integer 1,2 or 3, Alk5 is a straight or branched C1-6alkylene, C21-6alkenylene or C2-6alkynylene chain, optionally interrupted by one, two or three-O-or-S-atoms or-S (O) n- [where n is an integer 1 or 2] or-N (R12)- groups and R14 is a hydrogen or halogen atom or a group selected from alkyl,-OR'5 [where R15 is a hydrogen atom or an optionally substituted alkyl group],-SR'5,-NR15R'6 [where R'6 is as just defined for R"5 and may be the same or different], -NO2, -N3, -CN, - CO2R15, -SO3H, -SOR15, -SO2R15, -SO3R15, -OCO2R15, -CONR15R16, - OCONR15R16, -CSNR15R16, -COR15, -OCOR15, -N(R15)COR16, -N(R15)CSR16,

-SO2N(R15)(R16), -N(R15)SO2R16, -N(R15)CON(R16)(R17) [where R17 is as just defined for Rl*5],-N (R15) CSN (R16)(R17), -N(R15)SO2N(R16)(R17), aryl or a heteroaryl group.

When L4 and/or L5 is present in these substituents as a linker atom or group it may be any divalent linking atom or group as previously defined for L1.

When R14, R15, R16 and/or R17 is present as an optionally substituted alkyl group it may be an optionally substituted straight or branched Cl-alkyl group as previously generally and particularly defined or an optionally substituted C3- 8cycloalkyl group as previously defined for R5. Optional substituents which may be present on such groups include those optional substituents as previously described.

Additionally when the groups R15 and R16 or R15 and R17 groups these groups may be joined, together with the N atom to which they are attached, to form a heterocyclic ring. Such heterocyclic rings may be optionally interrupted by a further heteroatom or heteroatom containing group selected from -O-, -S-, -N(R15)-, -C(O)- or -C(S)- groups. Particular examples of such heterocyclic rings include piperidinyl, pyrazolidinyl, morpholinyl, thiomorpholinyl, pyrrolidinyl, imidazolidinyl and piperazinyl rings.

When Alk5 is present in or as a substituent it may be a chain as defined hereinbefore for the chain Alk3.

Aryl and heteroaryl groups represented by R14 include those aromatic and heteroaromatic groups as previously described in relation to the group G.

Optional substituents which may be present on these groups include those optional substituents described hereinbefore when G is an aromatic or heteroaromatic group.

Examples of the substituents represented by-L4 (Alk5) tL5 (R14) u when present as R13 substituents on heterocycles represented by the group B in compounds of

the invention include atoms or groups -L4Alk5L5R14, -L4Alk5R14, -Alk5L5R14, - L4R14 and -Alk5R14 wherein L4, Alk5, L5 and R14 are as defined above. Particular examples of such substituents include -L4CH2L5R14, -L4CH(CH3)L5R14, - L4CH (CH2) 2L5R14,-L4CH2R14,-L4CH (CH3) R14, -L4(CH2)2R14, -CH2R14, - CH (CH3) R14,-(CH2) 2R14,-CHCHR14,-CH2CHCHR14,-CCR14,-CH2CCR14 and- Regroups.

Thus R13 substituents which may be present on carbon-linked bicyclic heterocyclic group represented by B and/or B'in compounds of the invention may include for example one, two, three or more halogen atoms, e. g. fluorine, chlorine, bromine or iodine atoms, and/or C16alkyl, e. g. methyl, ethyl, n-propyl, i-propyl, n-butyl or t-butyl, C2-6alkenyl, e. g.-CHCH2,-CHCHCH3,-CH2CHCH2 or-CH2CHCHCH3, C2-6alkynyl, e. g.-CCH,-CCCH3,-CH2CCH or-CH2CCCH3, C37cycloalkyl, e. g. cyclobutyl, cyclopentyl, optionally substituted aryl, e. g. optionally substituted phenyl, optionally substituted heteroaryl, e. g. optionally substituted pyridyl, pyrimidinyl, pyrrolyl, furyl, thiazolyl, or thienyl, optionally substituted arylC1-6alkyl or heteroarylCl-6alkyl, e. g. optionally substituted benzyl, pyridylmethylenyl, thiazolmethylenyl, optionally substituted aryloxy, e. g. phenoxy, optionally substituted heteroaryloxy, e. g. optionally substituted pyridyloxy, thiazolyoxy, optionally substituted arylthio or heteroarylthio, e. g. optionally substituted phenylthio or pyridylthio, optionally substituted aryl1 6alkyloxy or heteroarylCl-6alkyloxy, e. g. optionally substituted benzyloxy, pyridylmethoxy, thiazolylmethoxy, optionally substituted arylC16alkylamino or heteroarylC16alkylamino, e. g. optionally substituted benzylamino, pyridylmethylamino, thiazolylmethylamino, optionally substituted aryl1 6alkylthio or heteroarylCl-6alkylthio, e. g. benzothio, pyridylmethylthio or thiazolylmethylthio C1-6hydroxyalkyl, e. g. hydroxymethyl, hydroxyethyl or- C (OH) (CF3) 2, carboxyC16alkyl, e. g. carboxyethyl, Cl-6alkylthio e. g. methylthio or ethylthio, carboxyC16alkylthio, e. g. carboxymethylthio, 2-carboxyethylthio or 3- carboxypropylthio, C16alkoxy, e. g. methoxy or ethoxy, hydroxyC16alkoxy, e. g.

2-hydroxyethoxy, haloC16alkyl, e. g.-CF3,-CHF2, CH2F, haloC16alkoxy, e. g.- OCF3,-OCHF2,-OCH2F, C1-6alkylamino, e. g. methylamino or ethylamino, amino (-NH2), aminoC1-6alkyl, e. g. aminomethyl or aminoethyl, C1-6dialkylamino,

e. g. dimethylamino or diethylamino, Cl-6alkylaminoC,-6alkyl, e. g. ethylaminoethyl, C1-6 dialkylaminoC1-6alkyl, e. g. diethylaminoethyl, aminoc,- 6alkoxy, e. g. aminoethoxy, C16alkylaminoC16alkoxy, e. g. methylaminoethoxy, C16dialkylaminoC16alkoxy, e. g. dimethylaminoethoxy, diethylaminoethoxy, diisopropylaminoethoxy, or dimethylaminopropoxy, nitro, azido, cyano, amidino, hydroxyl (-OH), formyl [HC (O)-], carboxyl (-C02H),-CO2AIk6 [where Alk6 is as defined above for Alk4], C16 alkanoyl e. g. acetyl, thiol (-SH), thioC16alkyl, e. g. thiomethyl or thioethyl, sulphonyl (-SO3H), C1-6alkylsulphonyl, e. g. methylsulphonyl, aminosulphonyl (-S02NH2), C1-6 alkylaminosulphonyl, e. g. methylaminosulphonyl or ethylaminosulphonyl, C16dialkylaminosulphonyl, e. g. dimethylaminosulphonyl or diethylaminosulphonyl, phenylaminosulphonyl, carboxamido (-CONH2), C16alkylaminocarbonyl, e. g. methylaminocarbonyl or ethylaminocarbonyl, C1-6dialkylaminocarbonyl, e. g. dimethylaminocarbonyl or diethylaminocarbonyl, aminoC16alkylaminocarbonyl, e. g. aminoethylamino- carbonyl, C1-6dialkylaminoC1-6alkylaminocarbonyl, e. g. diethylaminoethylaminocarbonyl, aminocarbonylamino, C1-6alkylaminocarbonyl- amino, e. g. methylaminocarbonylamino or ethy) aminocarbonyiamino, Ci- 6dialkylaminocarbonylamino, e. g. dimethylaminocarbonylamino or diethyl- aminocarbonylamino, C1-6alkylaminocabonylC1-6alkylamino, e. g. methylamino- carbonylmethylamino, aminothiocarbonylamino, C1-6alkylaminothiocarbonyl- amino, e. g. methylaminothiocarbonylamino or ethylaminothiocarbonylamino, C1-6dialkylaminothiocarbonylamino, e. g. dimethylaminothiocarbonylamino or diethylaminothiocarbonylamino, C16alkylaminothiocarbonylC16alkylamino, e. g. ethylaminothiocarbonylmethylamino, C1-6alkylsulphonylamino, e. g. methyl- sulphonylamino or ethylsulphonylamino, C16dialkylsulphonylamino, e. g. dimethylsulphonylamino or diethylsulphonylamino, aminosulphonylamino (- NHSO2NH2), C1-6alkylamino-sulphonylamino, e. g. methylaminosulphonylamino or ethylaminosulphonylamino, C1-6dialkylaminosulphonylamino, e. g. dimethyl- aminosulphonylamino or diethylaminosulphonylamino, C16alkanoylamino, e. g. acetylamino, aminoC16alkanoylamino e. g. aminoacetylamino, Cl-6dialkylamino- C16alkanoylamino, e. g. dimethylaminoacetylamino, C1-6alkanoylaminoC1-6alkyl, e. g. acetylaminomethyl, C1-6alkanoylaminoC1-6alkylamono, e. g. acetamido-

ethylamino, C16alkoxycarbonylamino, e. g. methoxycarbonylamino, ethoxy- carbonylamino or t-butoxycarbonylamino groups.

Where desired, two R13 substituents may be linked together to form a cyclic group such as a cyclic ether, e. g. a C16alkylenedioxy group such as methylenedioxy or ethylenedioxy.

The presence of certain substituents in the compounds of formula (1) may enable salts of the compounds to be formed. Suitable salts include pharmaceutically acceptable salts, for example acid addition salts derived from inorganic or organic acids, and salts derived from inorganic and organic bases.

Acid addition salts include hydrochlorides, hydrobromides, hydroiodides, alkylsulphonates, e. g. methanesulphonates, ethanesulphonates, or isothionates, arylsulphonates, e. g. p-toluenesulphonates, besylates or napsylates, phosphates, sulphates, hydrogen sulphates, acetates, trifluoroacetates, propionates, citrates, maleates, fumarates, malonates, succinates, lactates, oxalates, tartrates and benzoates.

Salts derived from inorganic or organic bases include alkali metal salts such as sodium, lithium or potassium salts, alkaline earth metal salts such as magnesium or calcium salts, and organic amine salts such as ammonia, morpholine, piperidine, dimethylamine, trimethylamine, diethylamine, triethylamine, cyclohexylamine or tris (hydroxymethyl) aminomethane salts.

Particularly useful salts of compounds according to the invention include pharmaceutically acceptable salts, especially base addition pharmaceutically acceptable salts.

One particular class of compounds of formulae (1) and (1c) is that wherein the group G'has the formula (1 b) in which the furanose sugar is preferably in the configuration, preferably the p-D-configuration, most preferably the ß-D-

ribofuranose configuration. Particularly useful compounds of the invention include those where Y'is a hydroxyl (-OH) group.

A particularly useful group of compounds according to the invention has the formula (2a): wherein: D, E and F is each a carbon or nitrogen atom provided that no more than two of D, E and F is a nitrogen atom; Z'is a hydroxyl (-OH), amino (-NH2) or azido (-N3) group; G, is as previously defined for compounds of formula (1); n and m is each as previously defined for compounds of formula (1); the ribose sugar is of natural ß-D configuration as shown; h is zero or the integer 1,2, 3 or 4; R13 is an optional substituent as previously defined which may be on any available carbon atom of the heterocyclic ring B' ; and the salts, solvates, hydrates and N-oxides thereof.

A further particularly useful group of compounds according to the invention has the formula (2b):

wherein: Q is a N atom or a CH or C (R13) group; M is an oxygen or sulphur atom or an NH or N (R13) group; Z'is a hydroxyl (-OH), amino (-NH2) or azido (-N3) group; G is as previously defined for compounds of formula (1); n and m is each as previously defined for compounds of formula (1); the ribose sugar is of natural P-D configuration as shown; h is zero or the integer 1,2, 3 or 4; R13 is an optional substituent as previously defined which may be on any available carbon or nitrogen atom of the heterocyclic ring B' ; and the salts, solvates, hydrates and N-oxides thereof.

In compounds of formula (1), (2a) and (2b) Z'is preferably a hydrogen atom or most preferably a hydroxyl (-OH) group.

In one particularly useful class of compounds of formula (1), (1c), (2a) and (2b) G is preferably a hydrogen atom or an optionally substituted aliphatic, heteroaliphatic, cycloaliphatic, polycycloaliphatic, aromatic or heteroaromatic group or a group of formula (1a) :

as hereinbefore generally and particularly defined.

When G is a group of formula (1 a) Y and Z is each preferably a hydrogen atom or a hydroxyl group. Most preferably Y and Z is each a hydroxyl (-OH) group.

When G is an optionally substituted aliphatic group it may in particular be an optionally substituted C16alkylene, C26alkenylene or C26alkynylene group as hereinbefore defined.

When G is an optionally substituted heteroaliphatic group it may in particular be an optionally substituted aliphatic group as just defined but additionally containing one, two, three or four L1 atoms or groups where L'is preferably an -O-or-S-atom or an-N (R1)-, especially-N (CH3)- group.

Particularly preferred optional substituents which may be present on aliphatic and heteroaliphatic groups represented by G include one, two or three substituents where each substituent may be the same or different and is selected from halogen atoms, e. g. fluorine, chlorine, bromine or iodine atoms, or hydroxyl (-OH), C16alkoxy, e. g. methoxy or ethoxy, C1_6haloalkoxy, e. g. trifluoromethoxy or difluoromethoxy, thiol (-SH), C16alkylthio e. g. methylthio or ethylthio or optionally substituted cycloaliphatic, especially cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl, heterocycloaliphatic, especially tetrahydrofuranyl, dihydrofuranyl or tetrahydropyranyl, aromatic, especially phenyl or heteroaromatic, especially thienyl, furanyl, pyridyl or pyrimidinyl groups.

When G is an optionally substituted cycloaliphatic group it may in particular be an optionally substituted C37cycloalkyl or C3-7cycoalkenyl group as hereinbefore defined.

When G is an optionally substituted polycycloaliphatic group it may in particular be an optionally substituted C7_iobi-or tricycloalkyl group.

Particular examples of cycloaliphatic and polycycloaliphatic groups represented by the group G include optionally substituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, 2-cyclobuten-1-yl, 2- cyclopenten-1-yl, 3-cyclopenten-1-yl, adamantyl, norbornyl, and norbornenyl, groups.

Particularly preferred optional substituents which may be present on cycloaliphatic and polycycloaliphatic groups represented by the group G include one, two, three or more substituents selected from halogen atoms, or C16alkyl, e. g. methyl or ethyl, haloC16alkyl, e. g. halomethyl or haloethyl such as difluoromethyl or trifluoromethyl, optionally substituted by hydroxyl, e. g.- C (OH) (CF3) 2, hydroxyl (-OH), C16alkoxy, e. g. methoxy or ethoxy, halo1 6alkoxy, eg. halomethoxy or haloethoxy such as difluoromethoxy or trifluoromethoxy, thiol (-SH), C16alkylthiol, e. g. methylthiol or ethylthiol or optionally substituted cycloalphatic, heterocycloaliphatic, aromatic or heteroaromatic groups.

Optionally substituted cycloaliphatic, heterocycloaliphatic, aromatic or heteroaromatic groups when present as optional substituents on the cycloaliphatic and polycycloaliphatic groups represented by the group G include those optionally substituted cycloaliphatic, heterocycloaliphatic, aromatic or heteroaromatic groups as described hereinbefore in relation to optional substituents on preferred aliphatic or heteroaliphatic groups represented by G.

Particularly useful R13 substituents when present in compounds of formulae (1), (1c), (2a) or (2b) include halogen atoms, especially fluorine or chlorine atoms, or straight or branched C16alkyl groups, especially methyl, ethyl, propyl or isopropyl groups, C2-6alkenyl, especially-CHCH2 and-CHCHCH3, C16alkynyl, especially-CCH and-CCCH3, C38cycloalkyl groups, especially cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl groups, haloC16alkyl groups, especially halomethyl groups, especially-CF3 and-CHF2 groups, C16alkoxy groups, especially methoxy or ethoxy groups, haloC16alkoxy groups, especially

halomethoxy groups, most especially-OCF3 or-OCHF2 groups, C16alkylthiol groups, especially methylthiol or ethylthiol groups,-CN,-C02AIk6, especially- C02CH3 and-C02C (CH3) 3,-N02, amino (-NH2), substituted amino (-NR15R16), <BR> <BR> <BR> especially-NHCH3 and-N (CH3) 2, -N (R'5) CoR16, especially-NHCOCH3 and- CoR15, especially-COCH3 groups. In one particular group of compounds of this type R13 is selected from fluorine, chlorine, methyl, methoxy or-CF3.

The particularly useful R13 substituents as just described also represent particularly useful optional substituents in general on aromatic and heteroaromatic groups when present in compounds of the invention.

In one preferred group of compounds of formulae (1), (1 c), (2a) or (2b) h is zero or the integer 1 or 2.

In one preferred class of compounds of formulae (2a) D and E is each a carbon atom and F is a nitrogen atom.

In another preferred class of compounds of formulae (2a) D and F is each a carbon atom and E is a nitrogen atom.

In another preferred class of compounds of formulae (2a) E and F is each a carbon atom and D is a nitrogen atom.

In another particularly preferred class of compounds of formulae (2a) E and F is each a nitrogen atom and D is a carbon atom.

In one preferred class of compounds of formulae (2b) M is an oxygen atom and Q is a CH or C (R13) group, where R13 is preferably a-CH3 group.

In another preferred class of compounds of formulae (2b) M is an sulphur atom and Q is a CH or C (R13) group, where R13 is preferably a-CH3 group.

In another preferred class of compounds of formulae (2b) M is an NH or N (R13), especially N (CH3) group and Q is a CH or C (R13) group, where R13 is preferably a-CH3 group.

In a particularly preferred class of compounds of formulae (2b) Q is a N atom and M is an oxygen or sulphur atom or NH or N (R13a), especially N (CHs) group.

In another particularly preferred class of compounds of formulae (1), (1c), (2a) and (2b) G is a hydrogen atom. In this class of compounds m is preferably the integer 1 and n is preferably zero.

In another preferred class of compounds of formulae (1), (1c), (2a) and (2b) G is a nucleoside of formula (1a) in which the furanose sugar is preferably in the 0-conf igu ration, preferably the (3-D-configuration, most preferably the (3-D- ribofuranose configuration as shown in formula (2c): where the letter b indicates the point of attachment to the remainder of the compound of formula (1), (1c), (2a) or (2b). In this class of compounds m and n is each preferably the integer 1. In one preferred group of compounds of this class the heterocycle B is a group of formula (2d):

wherein h is as previously defined, c represents the point of attachment to the remainder of the molecule of formula (2c) and D, E, F and R13 are as previously generally defined and particularly defined in relation to compounds of formula (2a). In another preferred group of compounds of this class the heterocycle B is a group of formula (2e): wherein h and c are as previously defined and Q, M and R13 are as previously generally defined and particularly defined in relation to compounds of formula (2b).

A most preferred group of compounds of the invention is that where G is a group of formula (1a) and G'is a group of formula (1b) in which the optionally substituted heterocycles B and B'is each a group of formula (2d) or is each a group of formula (2e). Especially preferred is a compound of formula (2a) in which G is a group of formula (2c) in which B is a group of formula (2d), most preferably where B and B'are identical or a compound of formula (2b) in which G is a group of formula (2c) in which B is a group of formula (2e), most preferably where B and B'are identical.

A further most preferred group of compounds of the invention is that where G is a group of formula (1 a), most preferably the (3-D-ribofuranose configuration and G'is a group of formula (1 b), most preferably the (3-D-ribofuranose configuration in which B is an optionally substituted heterocycle of formula (2d) and B'is an optionally substituted heterocycle of formula (2e).

In another preferred group of compounds of formulae (1), (2a) and (2b) G is a C16alkyl group, especially a methyl, ethyl, propyl, isopropyl or t-butyl group, a haloC16alkyl group, especially a trifluoromethyl or difluoromethyl group, a Ci- 6heteroalkyl group, especially ethyloxymethyl, propyloxymethyl or butyloxymethyl group, an optionally substituted C3_7heterocycloalkylCi-6alkyl group, especially an optionally substituted tetrahydrofuranylmethyl or dihydrofuranylmethyl group, an optionally substituted C610arylC16alkyl group, especially an optionally substituted benzyl or phenylethyl group, an optionally substituted C19heteroarylC16alkyl group, especially an optionally substituted pyridylmethyl, thienylmethyl, furanylmethyl or pyrimidinylmethyl group, an optionally substituted C37cycloalkylC16alkyl group, especially an optionally substituted cyclopropylmethyl, cyclopentylmethyl or cyclohexylmethyl group, an optionally substituted C3-7heterocycloalkyl group, especially an optionally substituted morpholinyl, thiomorpholinyl, piperidinyl, piperazinyl or pyrrolidinyl group, an optionally substituted Ce-ioaromatic group, especially an optionally substituted phenyl group or an optionally substituted C19heteroaromatic group, especially an optionally substituted pyridyl, pyrimidinyl, thienyl or furanyl group.

In one most preferred group of compounds of formulae (1), (2a) and (2b) G is a C16alkyl group, especially a methyl, ethyl, propyl, isopropyl or t-butyl group, a haloC16alkyl group, especially a trifluoromethyl or difluoromethyl group, a Ci- 6heteroalkyl group, especially ethyloxymethyl, propyloxymethyl or butyloxymethyl group, an optionally substituted C37heterocycloalkylC16alkyl group, especially an optionally substituted tetrahydrofuranylmethyl or dihydrofuranylmethyl group, an optionally substituted C6-loarylCl-6alkyl group, especially an optionally substituted benzyl or phenylethyl group, an optionally substituted C19heteroarylC16alkyl group, especially an optionally substituted pyridylmethyl, thienylmethyl, furanylmethyl or pyrimidinylmethyl group, an optionally substituted C37cycloalkylC16alkyl group, especially an optionally substituted cyclopropylmethyl, cyclopentylmethyl or cyclohexylmethyl group, an optionally substituted C6-loaromatic group, especially an optionally substituted phenyl group or an optionally substituted C19heteroaromatic group, especially an optionally substituted pyridyl, pyrimidinyl, thienyl or furanyl group.

Particularly useful compounds according to the invention are: (2R, 3S, 4R, 5R)-3, 4-Dihydroxy-5-benzothiazol-2-yl-tetrahydrofuran-2-ylmethyl triphosphate tris-ammonium salt ; (2R, 3S, 4R, 5R)-3, 4-Dihydroxy-5- (5-trifluoromethyl-benzothiazol-2-yl)- tetrahydrofuran-2-ylmethyl triphosphate tris-ammonium salt ; and the free acid, other pharmaceutical acceptable salts, solvates, hydrates and N-oxides thereof.

Further particularly useful compounds according to the invention are: (2R, 3S, 4R, 5R)-3, 4-Dihydroxy-5-(6-chlorobenzothiazol-2-yl)-tetrahydrofuran- 2-ylmethyl triphosphate tris-ammonium salt ; (2R, 3S, 4R, 5R)-3, 4-Dihydroxy-5- (5-fluorobenzothiazol-2-yl)-tetrahydrofuran-2- ylmethyl triphosphate tris-triethylammonium salt ; (2R, 3S, 4R, 5R)-5-(6-Chloro-4-fluorobenzothiazol-2-yl)-3, 4-dihydroxy- tetrahydrofuran-2-ylmethyl triphosphate tris-triethylammonium salt ; and the free acid, other pharmaceutical acceptable salts, solvates, hydrates and N-oxides thereof.

The compounds of the invention may be prepared by a number of processes as generally described below and more specifically in the Examples hereinafter.

In the following process description, the symbols G, G', B, B', m and n when used in the formulae depicted are to be understood to represent those groups described above in relation to formula (1) unless otherwise indicated. In the reactions described below, it may be necessary to protect reactive functional groups, for example hydroxy, amino, thio, phosphate or carboxy groups, where these are desired in the final product, to avoid their unwanted participation in the reactions. Conventional protecting groups may be used in accordance with standard practice [see, for example, Green, T. W. in"Protective Groups in Organic Synthesis", John Wiley and Sons, 1999 and the Examples hereinafter]. In some instances, deprotection may be the final step in the synthesis of a compound of formula (1) and the processes according to the invention described hereinafter are to be understood to extend to such removal of

protecting groups. For convenience the processes described below all refer to a preparation of a compound of formula (1) but clearly the description applies equally to the preparation of compounds of formulae (1 c), (2a) or (2b).

Thus according to a further aspect of the invention a triphosphate of formula (1) [in which G is a hydrogen atom, n is zero and m is the integer 1] may be prepared by reaction of a compound of formula (3): with a bis (tri-alkylammonium) pyrophosphate, for example bis (tri-n- butylammonium) pyrophosphate in the presence of an organic base such as a trialkylamine, e. g. tributylamine in an anhydrous solvent e. g. an amide such as dimethylformamide or a sulfoxide such as dimethyl sulfoxide at a temperature from around 0 to 80°C, optionally followed by purification of the product (1) by for example ion exchange chromatography using a Luna C18 column eluting with an ammonium acetate buffer or aqueous formic acid or an anion exchange resin such as DEAE-A25 sephadex or Q-sepharose HP eluting with for example an ammonium salt buffer such as triethylammonium bicarbonate or ammonium bicarbonate. Such methods of preparing compounds of formula (1) are well known and may be found in for example Kovacs, T. , Tetrahedron Letters 1988,29, 4525; Burgess, K. and Cook, D. , Chem. Rev., 2000, 100, 2047.

Compounds of formula (1) in the ammonium ion salt form may be readily converted to other salt forms, for example the sodium salt form, by treatment with a cation exchange resin such as DOWEX@-50 in its Na+ form.

Intermediates of formula (3) may be obtained by the reaction of a compound of formula (1 b) [where b now represents an-OH group] with a phosphorylating agent, for example phosphorous oxychloride in the presence

of a weakly nucleophilic strong organic base such as Proton Sponger in an anhydrous organic solvent, e. g. a phosphate such as trimethylphosphate or triethylphosphate at a low temperature, e. g. around 0°C. Such methods of preparing intermediates of formula (3) are well known and may be found in for example Yoshikawa, M. et al, Bull. Chem. Soc. Jpn. 1969,42, 3505.

In a further procedure compounds of formula (1) in which G is other than a hydrogen atom and n and m is each the integer 1 may be prepared by reaction of the tri-n-butylammonium salt of a compound of formula (1) in which G is a hydrogen atom, n is zero and m is the integer 1 with an activating agent such as carbonyldiimidazole or a dialkyl carbodiimide, e. g. dicyclohexyl carbodiimide in the presence of an ammonium salt e. g. tri-n-butylammonium salt of a monophosphate of formula (4); in a polar aprotic organic solvent such as a formamide e. g. dimethylformamide, a sulfoxide e. g. dimethylsulfoxide, a pyrrolidine e. g. N- methyl pyrrolidine, a phosphate e. g. triethylphosphate, a cyclic ether e. g. dioxane or an amine e. g. pyridine at a temperature from 0 to about 60°C. Purification of the resulting compounds of formula (1) may be achieved by any of the previously mentioned ion exchange procedures or by high performance liquid chromatography.

Methods of preparing monophosphates of formula (4) are well known in the art and may be found in for example Slotin, L. A. , Synthesis, 1977,737 ; Yoshikawa, M. , et al, Bull. Chem. Soc. Jpn. , 1969,42, 3505.

In an alternative procedure for the preparation of compounds of formula (1) in which G is a group of formula (1 a), G'is a group of formula (1b), n and m is each the integer 1 and the heterocyclic groups B and B'are the same a diphosphate of formula (1d) [G is a hydrogen atom and n and m is each zero];

may be condensed with a further diphosphate of formula (1d) using any of the above mentioned activating agents.

Diphosphates of formula (1d) may be obtained from intermediate salts of formula (5): by reaction with a trialkylammonium phosphate salt e. g. bis (tri-n- butylammonium) orthophosphate in an anhydrous organic solvent such as anhydrous pyridine at around ambient temperature or in a phosphate solvent such as triethylphosphate at an elevated temperature e. g around 50°C, as described by Moffatt, J. G. et al, J. Am. Chem. Soc. 1961,83, 649-658 and Can. J. Chem. 1964,42, 599-604.

Intermediates of formula (5) may be obtained by reaction of a salt of formula (6):

[or the free acid of a compound of formula (6) ] with an activating agent such as a dialkyl carbodimide e. g dicyclohexyl carbodimide or a carbonylimidazole, in the presence of an organic amine such as a cyclic amine e. g. morpholine [as depicted for formula (5) ] in a solvent e. g. an alcohol such as t-butanol, i- propanol, ethanol or methanol in the presence of added water at a temperature from ambient to the reflux temperature.

In a further procedure for the preparation of compounds of formula (1) intermediates of formula (5) may be converted to triphosphates of formula (1) [in which G is a hydrogen atom, n is zero and m is the integer 1] by reaction with pyrophosphate (preferably as its tri-n-butylammonium salt) in an anhydrous polar aprotic solvent, for example dimethyl sulfoxide at for example ambient temperature.

Intermediate compounds of formula (1a) and (1b) [where b now represents an-OH group] may be prepared by the methods described hereinafter or by such well known methods as for example those of Bobek, M. et al, Collect.

Czech Chem. Commun. , 1968,34, 247-252; EI Khadem, H. S. et al, Carbohydrate Res., 1986, 153,271-283 ; Szabo, I. F. et al, Acta Chimica Acad. Sci. Hung. , 1982,109, 229-236; Dudfield, P. J. et al, J. Chem. Soc., Perkin Trans. 1,1999, 2937-42; He, W. et al, J. Chem. Soc. , Perkin Trans. 1, 1998,2425-34 ; Yokoyama, M. et al, J. Chem. Soc. , Perkin Trans. 1,1996, 2145-49, Gudmunsson, K. S. et al, Tetrahedron Lett. , 1996,37, 2365-8 ; Vismara, E. et al, Tetrahedron Lett. , 1992,33, 7575-8; Togo, H. et al, Tetrahedron Lett. , 1991,32, 6559-62; Lopez Herrera, F. J. et al, J. Chem.

Soc. , Perkin Trans. 1,1989, 2401-6; Frick, W. et al, Liebigs Ann. Chem., 1989,565-70 ; Rao, S. P. et al, Tetrahedron Lett. , 1988,3537-40 ; Rosowsky,

A. et al, Carbohydr. Res. , 1988,176, 47-58; Cupps, T. L. et al, J. Org.

Chem. , 1986,51, 1058-64; Yokoyama, M. et al, Chem. Lett. , 1994,265-8 ; Yokoyama, M. et al, Synthesis, 1993,517-20 ; Guianvarc'h, D. et al, Tetrahedron Lett. , 2001,647-50 ; Yokoyama, M. et al, J. Chem. Soc. , Perkin Trans. 1,1997, 29-33; Yokoyama, M. et al, Heteroat. Chem. , 1995,6, 189- 93; Kim, G. et al, Tetrahedron Lett. , 2000,225-227 ; Maeba, l. et al, J. Org.

Chem. , 1988,53, 1401-5 and Japanese patent application JP 07118268.

Where in the general processes described above intermediates such as those of formulae (1a), (1b), (1d), (3), (4), (5) and (6) are not commercially available or known in the literature they may be readily obtained from simpler known compounds by one or more standard synthetic methods employing substitution, oxidation, reduction or cleavage reactions. Particular substitution approaches include conventional alkylation, arylation, heteroarylation, acylation, thioacylation, halogenation, sulphonylation, nitration, formylation and coupling procedures. It will be appreciated that these methods may also be used to obtain or modify other compounds of formulae (1), (1c), (2a) and (2b) and also to further functionalize intermediates of formulae (1 a), (1 b), (1 d), (3), (4), (5) and (6) where appropriate functional groups exist in these compounds.

Thus intermediates of formulae (1a), (1b), (1d), (3), (4), (5) and (6) and any other intermediates described herein required to obtain compounds of formula (1) may be prepared by methods known to those skilled in the art following procedures set forth in references such as Rodd's Chemistry of Carbon Compounds, Volumes 1-15 and Supplementals (Elsevier Science Publishers, 1989), Fieser and Fieser's Reagents for Organic Synthesis, Volumes 1-19 (John Wiley and Sons, 1999), Comprehensive Heterocyclic Chemistry, Ed. Katritzky et al, Volumes 1-8,1984 and Volumes 1-11,1994 (Pergamon), Comprehensive Organic Functional Group Transformations, Ed. Katritzky et al, Volumes 1-7,1995 (Pergamon), Comprehensive Organic Synthesis, Ed. Trost and Flemming, Volumes 1-9, (Pergamon, 1991), Encyclopedia of Reagents for Organic Synthesis Ed. Paquette, Volumes 1-8 (John Wiley and Sons, 1995), Larock's Comprehensive Organic

Transformations (VCH Publishers Inc., 1989) and March's Advanced Organic Chemistry (John Wiley and Sons, 5th edition, 2001) Compounds of the invention and intermediates thereto may be prepared by alkylation, arylation or heteroarylation. For example, compounds containing a- L3H or-L4H group (where L3 and L4 is each a linker atom or group) may be treated with an alkylating agent R9 (Alk2) qZ' or (R14)uL5 (Alk5) tZ' respectively in which Z'is a leaving atom or group such as a halogen atom, e. g. a fluorine, bromine, iodine or chlorine atom or a sulphonyloxy group such as an alkylsulphonyloxy, e. g. trifluoromethylsulphonyloxy or arylsulphonyloxy, e. g. p- toluenesulphonyloxy group.

The reaction may be carried out in the presence of a base such as a carbonate, e. g. caesium or potassium carbonate, an alkoxide, e. g. potassium t-butoxide, or a hydride, e. g. sodium hydride, in a dipolar aprotic solvent such as an amide, e. g. a substituted amide such as dimethylformamide or an ether, e. g. a cyclic ether such as tetrahydrofuran.

In another example, compounds containing a-L3H or-L4H or group as defined above may be functionalised by acylation or thioacylation, for example by reaction with one of the alkylating agents just described but in which Z'is replaced by a-C (O) Z2, C (S) Z2,-N (R2) COZ2or-N (R2) C (S) Z2 group in which Z2 is a leaving atom or group as described for z1. The reaction may be performed in the presence of a base, such as a hydride, e. g. sodium hydride or an amine, e. g. triethylamine or N-methylmorpholine, in a solvent such as a halogenated hydrocarbon, e. g. dichloromethane or carbon tetrachloride or an amide, e. g. dimethyl-formamide, at for example ambient temperature. Alternatively, the acylation may be carried out under the same conditions with an acid (for example one of the alkylating agents described above in which Z'is replaced by a-C02H group) in the presence of a condensing agent, for example a diimide such as 1- (3-dimethylaminopropyl)-3-ethylcarbodiimide or N, N'- dicyclohexylcarbodiimide, or a benzotriazole such as [0-(7-azabenzo-triazol-1- yl)-1, 1,3, 3-tetramethyluronium] hexafluorophosphate advantageously in the

presence of a catalyst such as a N-hydroxy compound e. g. a N-hydroxytriazole such as 1-hydroxybenzotriazole. Alternatively the acid may be reacted with a chloroformate, for example ethylchloroformate, prior to the desired acylation reaction In a further example compounds may be obtained by sulphonylation of a compound containing an-OH group by reaction with one of the above alkylating agents but in which Z'is replaced by a-S (O) Hal or-S02Hal group [in which Hal is a halogen atom such as chlorine atom] in the presence of a base, for example an inorganic base such as sodium hydride in a solvent such as an amide, e. g. a substituted amide such as dimethylformamide at for example ambient temperature.

In another example, compounds containing a-L3H or-L4H group as defined above may be coupled with one of the alkylation agents just described but in which Z'is replaced by an-OH group in a solvent such as tetrahydrofuran in the presence of a phosphine, e. g. triphenylphosphine and an activator such as diethyl, diisopropyl-or dimethylazodicarboxylate.

In a further example, ester groups-C02R6,-CO2Alk4,-C02AIk6 or-C02R'5 in the compounds may be converted to the corresponding acid [-C02H] by acid- or base-catalysed hydrolysis depending on the nature of the groups R6, Alk4, Alk6 or R15. Acid-or base-catalysed hydrolysis may be achieved for example by treatment with an organic or inorganic acid, e. g. trifluoroacetic acid in an aqueous solvent or a mineral acid such as hydrochloric acid in a solvent such as dioxan or an alkali metal hydroxide, e. g. lithium hydroxide in an aqueous alcohol, e. g. aqueous methanol.

In a further example,-OR6 or-OR"groups [where R6 or R"each represents an alkyl group such as methyl group] in compounds of formula (1) may be cleaved to the corresponding alcohol-OH by reaction with boron tribromide in a solvent such as a halogenated hydrocarbon, e. g. dichloromethane at a low temperature, e. g. around-78°C.

Alcohol [-OH] groups may also be obtained by hydrogenation of a corresponding-OCH2R3° group (where R30 is an aryl group) using a metal catalyst, for example palladium on a support such as carbon in a solvent such as ethanol in the presence of ammonium formate, cyclohexadiene or hydrogen, from around ambient to the reflux temperature. In another example,-OH groups may be generated from the corresponding ester [e. g. C02AIk2 or CO2R6] or aldehyde [-CHO] by reduction, using for example a complex metal hydride such as lithium aluminium hydride or sodium borohydride in a solvent such as methanol.

In another example, alcohol-OH groups in the compounds may be converted to a corresponding-OR6 or-OR"group by coupling with a reagent R6OH or R11OH in a solvent such as tetrahydrofuran in the presence of a phosphine, e. g. triphenylphosphine and an activator such as diethyl-, diisopropyl-, or dimethylazodicarboxylate.

Aminosulphonylamino [-NHS02NHR7] groups in the compounds may be obtained, in another example, by reaction of a corresponding amine [-NH2] with a sulphamide R'NHS02NH2 in the presence of an organic base such as pyridine at an elevated temperature, e. g. the reflux temperature.

In another example compounds containing a-NHCSR11 or-CSNHR16, may be prepared by treating a corresponding compound containing a-NHCOR"or- CONHR16 group with a thiation reagent, such as Lawesson's Reagent or P2S5, in an anhydrous solvent, for example a cyclic ether such as tetrahydrofuran, at an elevated temperature such as the reflux temperature.

In a further example amine (-NH2) groups may be alkylated using a reductive alkylation process employing an aldehyde and a borohydride, for example sodium triacetoxyborohyride or sodium cyanoborohydride, in a solvent such as a halogenated hydrocarbon, e. g. dichloromethane, a ketone such as acetone,

or an alcohol, e. g. ethanol, where necessary in the presence of an acid such as acetic acid at around ambient temperature.

In a further example, amine [-NH2] groups in compounds of formula (1) may be obtained by hydrolysis from a corresponding imide by reaction with hydrazine in a solvent such as an alcohol, e. g. ethanol at ambient temperature.

In another example, a nitro [-N02] group may be reduced to an amine [-NH2], for example by catalytic hydrogenation using for example hydrogen in the presence of a metal catalyst, for example palladium on a support such as carbon in a solvent such as an ether, e. g. tetrahydrofuran or an alcohol e. g. methanol, or by chemical reduction using for example a metal, e. g. tin or iron, in the presence of an acid such as hydrochloric acid.

In a further example amine (-CH2NH2) groups in compounds of formula (1) and intermediates thereto may be obtained by reduction of nitriles (-CN), for example by catalytic hydrogenation using for example hydrogen in the presence of a metal catalyst, for example palladium on a support such as carbon, or Raneye nickel, in a solvent such as an ether e. g. a cyclic ether such as tetrahydrofuran or an alcohol e. g. methanol or ethanol, optionally in the presence of ammonia solution at a temperature from ambient to the reflux temperature, or by chemical reduction using for example a metal hydride e. g. lithium aluminium hydride, in a solvent such as an ether e. g. a cyclic ether such as tetrahydrofuran, at a temperature from 0°C to the reflux temperature.

Aromatic halogen substituents in the compounds may be subjected to halogen- metal exchange with a base, for example a lithium base such as n-butyl or t- butyl lithium, optionally at a low temperature, e. g. around-78°C, in a solvent such as tetrahydrofuran and then quenched with an electrophile to introduce a desired substituent. Thus, for example, a formyl group may be introduced by using dimethylformamide as the electrophile ; a thiomethyl group may be introduced by using dimethyldisulphide as the electrophile. Aromatic acids may be generated by quenching aromatic Grignard reagents with carbon dioxide.

In another example, sulphur atoms in the compounds, for example when present in a linker group L3 or L4 may be oxidised to the corresponding sulphoxide or sulphone using an oxidising agent such as a peroxy acid, e. g. 3- chloroperoxybenzoic acid, in an inert solvent such as a halogenated hydrocarbon, e. g. dichloromethane, at around ambient temperature.

N-oxides of compounds of formula (1) may be prepared for example by oxidation of the corresponding nitrogen base using an oxidising agent such as hydrogen peroxide in the presence of an acid such as acetic acid, at an elevated temperature, for example around 70°C to 80°C, or alternatively by reaction with a peracid such as peracetic acid in a solvent, e. g. dichloromethane, at ambient temperature.

Salts of compounds of formula (1) may be prepared by reaction of a compound of formula (1) with an appropriate base in a suitable solvent or mixture of solvents e. g. an organic solvent such as an ether e. g. diethylether, or an alcohol, e. g. ethanol or an aqueous solvent using conventional procedures.

Salts of compounds of formula (1) may be exchanged for other salts by use of conventional ion-exchange chromatography procedures.

Where it is desired to obtain a particular enantiomer of a compound of formula (1) this may be produced from a corresponding mixture of enantiomers using any suitable conventional procedure for resolving enantiomers.

Thus for example diastereomeric derivatives, e. g. salts, may be produced by reaction of a mixture of enantiomers of formula (1) e. g. a racemate, and an appropriate chiral compound, e. g. a chiral base. The diastereomers may then be separated by any convenient means, for example by crystallisation and the desired enantiomer recovered, e. g. by treatment with an acid in the instance where the diastereomer is a salt.

In another resolution process a racemate of formula (1) may be separated using chiral High Performance Liquid Chromatography. Alternatively, if desired a particular enantiomer may be obtained by using an appropriate chiral intermediate in one of the processes described above.

Chromatography, recrystallisation and other conventional separation procedures may also be used with intermediates or final products where it is desired to obtain a particular geometric isomer of the invention.

The following Examples illustrate the invention. All temperatures are in °C. The following abbreviations are used: NMM-N-methylmorpholine ; EtOAc-ethyl acetate; MeOH-methanol ; BOC-butoxycarbonyl ; DCM-dichloromethane ; AcOH-acetic acid ; DIPEA-diisopropylethylamine ; EtOH-ethanol ; Pyr-pyridine; DMF-N, N-dimethylformamide ; DMSO-dimethylsulphoxide ; iPr-isopropyl ; Et2O-diethylether ; Me-methyl ; THF-tetrahydrofuran ; RT-room temperature LCMS-liquid chromatography-mass spectroscopy NMR's were obtained at the indicated frequency (quoted as AH or 8 31p values) The compounds were named with the aid of Beilstein Autonom.

LCMS was performed on a Hewlett Packard 1100 LC/MSD instrument using a Phenomenex Luna 3µ C18 (2) 50 x 4.6 mm column and electrospray ionisation in +ve mode. Compounds were eluted with a mobile phase formed from solution A (0. 1% aqueous formic acid) and solution B (0. 1% formic acid in acetonitrile) with the following gradient and column conditions. Initial = 5% B, 2 min = 95% B, 3 min = 95% B, 5 min = 5% B; column temp 40° ; flow rate 0.9 ml min' ; detection UV DAD 210-450nM.

Intermediate 1 <BR> <BR> <BR> <BR> (2R, 3R, 4S, 5R)-2-Benzothiazol-2-vl-5-hvdroxvmethvl-tetrahvdrofuran-3, 4- diol tribenzoate A mixture of (2S, 3R, 4S, 5R)-3, 4-dihydroxy-5-hydroxymethyl-3-methoxy- tetrahydrofuran-2-carbonitrile tribenzoate (490mg), and 2-aminothiophenol (133, uL) in ethanol (10ml) under an atmosphere of nitrogen was heated at 50° for 2h then at reflux for 4h. The reaction was left to stand at room temperature overnight then adsorbed onto silica and purified by column chromatography (Si02 ; 30% EtOAc/hexane then 2% EtOAc/DCM) to give the title compound (366mg, 61%) as a while glassy solid. Rf 0.52 (30% EtOAc in hexane); 8H (300MHz, CDC13) 8.10-8. 00 (5H, m), 7.95 (2H, d), 7.80 (H, d), 7.60-7. 30 (11H, m), 6.10 (H, t), 5. 95 (H, t), 5.75 (H, d), 4.95-4. 80 (2H, m), 4.65 (H, dd); m/z 581 (M+1).

Intermediate2 <BR> <BR> <BR> <BR> (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (5-trifluoromethvi-benzothiazol-2-vl)- tetrahydrofuran-34-diol tribenzoate Prepared following the procedure for Intermediate 1 from (2S, 3R, 4S, 5R) -3, 4- hydroxy-5-hydroxymethyl-3-methoxy-tetrahydrofuran-2-carbonit rile tribenzoate (700mg), 2-amino-4-trifluoromethyl-benzenethiol hydrochloride (375mg) and triethylamine (0. 23ml) in ethanol (15ml), refluxing for 5h.

Purification by column chromatography (SiO2 ; 20% EtOAc/hexane then DCM) gave the title compound (400mg, 42%) as a cream solid. Rf 0.40 (DCM); 8H (300MHz, CDCl3) 8.25 (H, s), 8.05-7. 90 (7H, m), 7.65-7. 30 (10H, m), 6.10 (H, t), 5.95 (H, t), 5.75 (H, d), 4.95 (H, dd), 4.90-4. 80 (H, m), 4.60 (H, dd); m/z 649 (M+1).

Intermediate 3 <BR> <BR> <BR> <BR> (2R83Rz4St5R)-2-Benzothiazol-2-vl-5-hvdroxvmethvl-tetrahvdro furan-3d4- diol Intermediate 1 (366mg) was dissolved in MeOH (5ml) and DCM (3ml) under an atmosphere of nitrogen and cooled in an ice bath. Sodium methoxide (136mg) was added then the reaction allowed to warm to room temperature and stirred for 2h before quenching with ammonium chloride (270mg). The reaction was adsorbed onto silica and purified by column chromatography

(Si02 ; 30% EtOAc/hexane then 10% MeOH/EtOAc followed by 20% MeOH/EtOAc) to give the title compound (150mg, 89%) as a white solid. Rf 0.70 (10% MeO/EtOAc) ; 8H (300MHz, DMSO) 8.05 (H, d), 7.95 (H, d), 7.50 (H, t), 7.40 (H, t), 5.45 (H, d), 5.05 (H, d), 5.00 (H, d), 4.85 (H, t), 4.15-4. 10 (H, m), 3.95-3. 85 (2H, m), 3.65-3. 50 (2H, m); m/z 268 (M+1).

Intermediate 4 <BR> <BR> <BR> <BR> (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (5-trifluoromethvl-benzothiazol-2-vt)-<BR> <BR> <BR> <BR> <BR> tetrahvdrof uran-3, 4-diol Prepared following the procedure for intermediate 3 from Intermediate 2 (400mg) and sodium methoxide (133mg) in methanol (5ml) and DCM (3ml), quenching with ammonium chloride (265mg). Purification by column chromatography (SiO2 ; 30% EtOAc/hexane followed by 10% MeOH/EtOAc then Si02, 5% MeOH/EtOAc) gave the title compound (165mg, 77%) as a white solid. Rf 0.55 (5% MeOH/EtOAc); 6H (300MHz, DMSO) 8.40 (H, s), 8.35 (H, d), 7.75 (H, d), 5.50 (H, d), 5.15 (H, d), 5.05 (H, d), 4.90 (H, t), 4. 15- 4.10 (H, m), 4.00-3. 85 (2H, m), 3.65-3. 50 (2H, m); m/z 336 (M+1).

Intermediate 5 2-Amino-5-chloro-benzenethiol A mixture of 2-amino-6-chloro-benzothiazole (1.5g), sodium hydroxide (4.5g) and water (9ml) was heated at reflux under an atmosphere of nitrogen for 22h then left to cool. The reaction was poured onto 30m ! ice/water, cooled in an ice bath, acidified to pH 3 with 2N HCI then extracted with toluene (3x30m1). The extracts were washed with brine (40mi) and dried (MgS04).

The solvent was removed in vacuo to leave the title compound (833mg, 64%) as a yellow solid. Rf 0.73 (40% hexane/EtOAc); 8H (300MHz, DMSO) 7.20 (H, s), 6.95 (H, d), 6.70 (H, d), 5.35 (H, s).

Intermediate 6 (2R, 4Ss5R)-3s4-Dihvdroxv-5-hvdroxvmethvl-tetrahvdrofuran-2- carbothioic acid amide tribenzoate Lawesson's reagent (1.96g) was added to a solution of (2R, 3R, 4S, 5R) -3, 4- dihydroxy-5-hydroxymethyl-tetrahydrofuran-2-carboxylic acid amide (4.75g) in dioxane (50moi) in an ice-water bath. The mixture was stirred at room temperature for 64h. The mixture was filtered, concentrated and purified by

column chromatography (Si02 ; graded eluent 10% to 25% EtOAc/hexane) to give the title compound as a pale cream solid (3.32g, 68%). Rf 0.65 (50% EtOAc/hexane); 8H (300MHz, CDC13) 8.44 (H, broad s) 8.04-7. 96 (4H, m), 7.82 (2H, d), 7.60-7. 32 (7H, m) 7.28 (2H, t), 5.92 (H, t), 5.64 (H, t), 5.06 (H, d) and 4.70-4. 60 (3H, m); m/z 506 (M+1).

Intermediate 7 (2R, 3R, 4S, 5R)-2- (6-Chloro-benzothiazol-2-vl)-5-hvdroxvmethvl- tetrahvdro-furan-3, 4-diol tribenzoate Prepared following the procedure for Intermediate 1 from (2S, 3R, 4S, 5R) -3, 4- hydroxy-5-hydroxymethyl-3-methoxy-tetrahydrofuran-2-carbonit rile tribenzoate (733mg) and Intermediate 5 (288mg) in ethanol (15ml), refluxing for 4.5h. Purification by column chromatography (Si02 ; 30% EtOAc/hexane) gave the title compound (399mg, 40%) as a pale yellow solid. Rf 0.58 (30% EtOAc/hexane); 8H (300MHz, CDC13) 8.05-8. 00 (4H, m), 7.95-7. 85 (3H, m), 7.75 (H, s), 7.65-7. 30 (10H, m), 6.10 (H, t), 5.90 (H, t), 5.70 (H, d), 4.90 (H, dd), 4.85-4. 80 (H, m), 4.60 (H, dd); m/z 614 (M+1).

Intermediate 8 (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (6-methoxv-benzothiazol-2-vl)- tetrahvdro-furan-3, 4-diol tribenzoate Prepared following the procedure for Intermediate 1 from (2S, 3R, 4S, 5R) -3, 4- hydroxy-5-hydroxymethyl-3-methoxy-tetrahydrofuran-2-carbonit rile tribenzoate (1.5g) and 2-amino-5-methoxy-benzenethiol (0.8g) in ethanol (25ml), refluxing for 3h. Purification by column chromatography (Si02 ; 30% EtOAc/heptane) gave the title compound (1.2g, 62%) as a pale yellow oil. Rf 0.65 (30% EtOAc/heptane); 8H (300MHz, CDC13) 8.10-8. 05 (4H, m), 7.95- 7. 85 (3H, m), 7.60-7. 50 (3H, m), 7.45-7. 30 (6H, m), 7.25 (H, s), 7.05 (H, d), 6.10 (H, t), 5.95 (H, t), 5.75 (H, d), 4.95-4. 80 (2H, m), 4.65 (H, dd), 3.85 (3H, s); m/z 610 (M+1).

Intermediate 9 (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (4-methoxv-benzothiazol-2-vl)- tetrahvdro-furan-34-diol tribenzoate Prepared following the procedure for Intermediate 1 from (2S, 3R, 4S, 5R) -3, 4- hydroxy-5-hydroxymethyl-3-methoxy-tetrahydrofuran-2-carbonit rile

tribenzoate (0. 39g) and 2-amino-3-methoxy-benzenethiol (0.34g) in ethanol (30ml), refluxing for 18h. Purification by column chromatography (SiO2 ; 20% EtOAc/heptane) gave the title compound (0. 28g, 58%) as a pale yellow oil. Rf 0.48 (30% EtOAc/heptane); 8H (300MHz, CDCl3) 8.10-7. 30 (17H, m), 6.80 (H, d), 5.95 (H, t), 5.85 (H, t), 5.80 (H, d), 4.85 (H, dd), 4.70 (H, m), 4. 60 (H, dd), 3.95 (3H, s).

Intermediate 10 (2R 3Sq4Re5R)-5-(5-Fluorobenzothiazol-2-Yl)-2-hydroxymeth tetrahvdrofuran-3, 4-diol tribenzoate Intermediate 6 (505mg), 5-fluoro-2-iodoaniline (237mg), calcium oxide (56mg), tris (dibenzylideneacetone) dipalladium (0)-chloroform adduct (50mg), 1, 1'-bis-(diphenylphosphino) ferrocene (110mg) and dimethylformamide (1ml) were heated at 60°C under nitrogen for 2.5h. The mixture was allowed to cool, and purification by column chromatography (Si02 ; graded eluent 10% to 20% EtOAc/hexane) gave the title compound as a colourless gum (205mg, 31%). Rf 0.55 (30% EtOAc/hexane); 8H (300MHz, CDCl3) 8.04 (4H, d), 7.94 (2H, d), 7.74 (H, dd), 7.66 (H, dd), 7.64-7. 32 (9H, m) 7.16 (H, t of d), 6. 08 (H, t), 5.92 (H, t), 5.74 (H, d), 4.92 (H, dd), 4.84 (H, ddd) and 4.64 (H, dd); m/z 598 (M+1).

Intermediate 11 <BR> <BR> <BR> <BR> (2R, 3S, 4R, 5R)-5- (6-Chloro-4-fluorobenzothiazol-2-vl)-2-hydroxymethvt- tetra hydrofuran-3, 4-d iol tribenzoate Prepared following the procedure for Intermediate 10 from Intermediate 6 (606mg), 2-chloro-2-fluoro-6-iodoaniline (326mg), calcium oxide (67mg), tris (dibenzylideneacetone) dipalladium (0)-chloroform adduct (62mg), 1,1'-bis- (diphenylphosphino) ferrocene (133mg) and dimethylformamide (1. 2ml), heating at 60°C for 2h. Purification by column chromatography (Si02 ; graded eluent 10% to 20% EtOAc/hexane) gave the title compound as a colourless gum (146mg, 19%). Rf 0.5 (30% EtOAc/hexane); 8H (300MHz, CDCI3) 8. 06 (2H, d), 8.00 (2H, d), 7.94 (2H, d), 7.64-7. 50 (4H, m), 7.48-7. 30 (6H, m), 7.20 (H, dd), 6.06 (H, t), 5.94 (H, t), 5.76 (H, d), 4.94 (H, dd), 4.82 (H, ddd) and 4. 62 (H, dd); m/z 632 (M+1).

Intermediate 12

(2R, 3S, 4R, 5S)-2-Hvdroxvmethyl-5- (1-methvl-1H-benzoimidazol-2-vl)- tetrahvdro-furan-3, 4-diol tribenzoate Oxalyl chloride (0.5g) was added to a solution of (2R, 3R, 4S, 5R) -3, 4- dihydroxy-5-hydroxymethyl-tetrahydro-furan-2-carboxylic acid tribenzoate (0.35g) in DCM (40ml). A drop of DMF was added and the mixture stirred until all effervesence had ceased. Phenylenediamine (0.22g) was added and stirring continued overnight. The solvent was removed in vacuo, and the residue dissolved in toluene (20mi). Phosphorous oxychloride (0. 1g) and triethylamine (0.07g) were added, and the mixture heated to reflux overnight.

After cooling to rt it was cautiously quenched with a saturated aqueous solution of sodium bicarbonate. The organics were separated, dried (MgS04), evaporated and chromatographed (Si02 ; 30% EtOAc/hexane). The resulting residue was dissolved in THF (5ml) and sodium hydride (0.02g) was added. The mixture was stirred at rt for 10 min before addition of iodomethane (0.07g) and then overnight. The mixture was partitioned between water (20ml) and dichloromethane (20ml). The organics were dried (MgS04), evaporated and purified by chromatography (Si02 ; 4% methanol- DCM) to give the title compound as a light brown solid (180mg, 19%). Rf 0.75 (4% methanol-DCM) ; 8H (300MHz, CDC13) 8. 10 (2H, d), 8.00 (H, d), 7. 85 (2H, t), 7. 50-7. 40 (4H, m), 7.40-7. 25 (8H, m), 5.90 (H, t), 5.80 (H, t), 4.90 (H, d), 4.70-4. 60 (2H, m), 4.55-4. 45 (H, m), 3.40 (3H, s); m/z 577 (M+1).

Intermediate 13 <BR> <BR> <BR> <BR> <BR> (2R, 3S, 4R, 5S)-2-Hvdroxvmethvl-5- (1-methvl-1 H-benzoimidazol-2-vl)-<BR> <BR> <BR> <BR> <BR> <BR> <BR> tetrahvdro-furan-3. 4-diot Prepared following the procedure for Intermediate 3 from Intermediate 12 (180mg) and sodium methoxide (60mg) in methanol (3ml) and EtOAc (12ml).

Trituration with hexane gave the title compound (72mg, 87%) as a pale brown solid. Rf 0.41 (10% methanol-DCM ; 8H (300MHz, DMSO) 7.80 (H, d), 7.65 (H, d), 7.55-7. 45 (2H, m), 5.45 (H, d), 4.85 (2H, br s), 4.60 (H, br s), 4.55 (H, br s), 4.30 (H, m), 4.05 (H, dd), 4.05 (3H, s), 3.80 (H, dd); m/z 265 (M+1).

Intermediate14 <BR> <BR> <BR> (2R, 4S5R)-2-(6-Chloro-benzothiazol-2-vl)-5-hvdroxymethyl-<BR& gt; <BR> <BR> <BR> <BR> <BR> <BR> tetrahvdro-furan-3, 4-diol

Prepared following the procedure for Intermediate 3 from Intermediate 7 (399mg) and sodium methoxide (140mg) in methanol (5ml) and DCM (3ml), quenching with ammonium chloride (280mg). Purification by column chromatography (Si02 ; 30% EtOAc/hexane then EtOAc followed by 10% MeOH/EtOAc) gave the title compound (155mg, 79%) as a white solid. Rf 0.40 (EtOAc); 8H (300MHz, DMSO) 8.30 (H, d), 8.00 (H, d), 7.55 (H, dd), 5.50 (H, d), 5.15 (H, d), 5.05 (H, d), 4.90 (H, t), 4.15-4. 10 (H, m), 4.00-3. 90 (2H, m), 3.70-3. 55 (2H, m); m/z 302 (M+1).

Intermediate 15 <BR> <BR> <BR> <BR> (2R, R)-2-Hydroxvmethvl-5-(6-methoxv-benzothiazol-2-vl)-<BR> ; <BR> <BR> <BR> <BR> tetrahvdro-furan-3. 4-cHo) Prepared following the procedure for Intermediate 3 from Intermediate 8 (1.2g) and sodium methoxide (420mg) in methanol (10mi) and ethyl acetate (10ml), quenching with ammonium chloride (0.5g). Purification by column chromatography (Si02 ; 50: 45: 5 heptane/EtOAc/MeOH) gave the title compound (250mg, 43%) as a white solid. Rf 0.12 (50: 45: 5 heptane/EtOAc/MeOH); 8H (300MHz, CDC13) 7.85 (H, d), 7.30 (H, d), 7.10 (H, dd), 5.25 (H, d), 4.50-4. 40 (2H, m), 4.20-4. 25 (H, m), 3.90 (3H, s), 3.25 (H, d), 2.75 (H, d); m/z 298 (M+1).

Intermediate 16 (2R, 3S. 4R, 5R)-2-Hvdroxvmethvl-5- (4-methoxv-benzothiazol-2-vl)- tetrahvdro-furan-3, 4-diol Prepared following the procedure for Intermediate 3 from Intermediate 9 (0.28g) and sodium methoxide (0. 10g) in methanol (10ml) and DCM (10ml), quenching with ammonium chloride (0.20g). Purification by column chromatography (SiO2 ; 5% MeOH/DCM) to give the title compound (0. 118g, 88%) as a white solid. Rf 0. 28 (5% MeOH/DCM);) ; 8H (300MHz, DMSO) 7.4 (H, d), 7.1 (H, t), 6.8 (H, d), 5.2 (H, d), 4.8 (H, d), 4.75 (H, d), 4.6 (H, t), 3.9 (H, t), 3.7-3. 6 (2H, m), 3.7 (3H, s), 3.4-3. 3 (2H, m); m/z 298 (M+1).

Intermediate 17 (2R, 3R, 4S, 5R)-2- (5-Fluorobenzothiazol-2-vl)-5-hvdroxvmethvl- tetrahvdrofuran-3, 4-diol

Prepared following the procedure for Intermediate 3 from Intermediate 10 (280mg) and sodium methoxide (101mg) in methanol (5ml) and DCM (5ml), quenching with ammonium chloride (200mg). Purification by column chromatography (SiO2 ; 20% EtOAc/hexane followed by EtOAc) gave the title compound (66mg, 49%) as a beige solid. Rf 0.45 (EtOAc); 8H (300MHz, DMSO) 8.18 (H, dd), 7.86 (H, dd), 7.38 (H, t of d), 5.52 (H, d), 5.16 (H, d), 5.06 (H, d), 4.92 (H, t), 4.14 (H, q), 4.00-3. 90 (2H, m) and 3.68-3. 54 (2H, m); m/z 286 (M+1).

Intermediate 18 <BR> <BR> <BR> <BR> (2R, 3R, 4S, 5R)-2- (6-Chloro-4-fluoro-benzothiazol-2-vl)-5-hvdroxvmethvl-<BR > <BR> <BR> <BR> <BR> tetrahydrofuran-34-diol Prepared following the procedure for Intermediate 3 from Intermediate 11 (140mg) and sodium methoxide (48mg) in methanol (5ml) and DCM (5ml), quenching with ammonium chloride (100mg). Purification by column chromatography (SiO2 ; 20% EtOAc/hexane followed by EtOAc) gave the title compound (60mg, 80%) as a beige solid. Rf 0.45 (EtOAc); 8H (300MHz, DMSO) 8.04 (H, d), 7.48 (H, dd), 5.44 (H, d), 5.02 (H, d), 4.92 (H, d), 4.78 (H, t), 4.00 (H, q), 3.88-3. 76 (2H, m) and 3.54-3. 38 (2H, m); m/z 320 (M+1).

Intermediate 19 <BR> <BR> <BR> <BR> (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (5-methvl-benzooxazol-2-vl)-<BR> <BR> <BR> <BR> <BR> tetrahvdro-furan-3q4-diol (2R, 3R, 4S, 5R)-3, 4-Dihydroxy-5-hydroxymethyl-tetrahydro-furan-2- carboximidic acid methyl ester (320mg) was dissolved in THF (10mi).

Hydrogen chloride (5ml of a 1. ON solution in ether) was added and the mixture stirred for 15 min. The resulting solid was removed by filtration, washed with THF (50ml) and dissolved in methanol (20ml). 2-Amino-p-cresol (206mg) was added, and the mixture heated to reflux for 4h. The reaction mixture was adsorbed onto silica and purified by column chromatography (Si02 ; EtOAc followed by 5% MeOH/EtOAc) to give the title compound (150mg, 34%) as a white solid. Rf 0.36 (EtOAc); 8H (300MHz, DMSO) 7.65 (H, d), 7.60 (H, s), 7.30 (H, d), 5.45 (H, d), 5.20 (H, d), 4.80 (2H, d overlapping with t), 4.40 (H, t), 4.10 (H, t), 4. 00-3. 90 (H, m), 3.60-3. 40 (2H, m), 2.45 (3H, s); m/z 266 (M+1).

Example 1 (2R, 3S, 4R, 5R)-3, 4-Dihvdroxv-5-benzothiazol-2-vl-tetrahvdrofuran-2- vlmethvl triphosphate tris-ammonium salt Trimethylphosphate (2. 2ml) was added to a mixture of Intermediate 3 (150mg) and proton sponge (180mg) at room temperature under nitrogen.

The mixture was stirred at room temperature until all the solid had dissolved and was then cooled in an ice bath. Phosphorous oxychloride (0. 058ml) was added dropwise and the mixture stirred for 2 h before simultaneous addition of tributylamine (0. 56ml) and a 0.5M solution of tributylammonium pyrophosphate in DMF (5. 6ml). The mixture was stirred for a further 2.5 min then quenched by addition of aqueous ammonium bicarbonate (140mg in 14ml of water) and stirred for 2h. The volatile solvents were evaporated in vacuo and the residue purified by reverse phase ion-pair chromatography on a Luna C18 column eluting with an ammonium acetate buffer. Fractions containing the desired triphosphate were extracted onto an ion exchange SPE cartridge which was eluted with 10% aqueous ammonia to give, after evaporation of the solvent in vacuo, the title compound as a white gum (23mg). 8H (400MHz, D20) 8. 10 (H, d), 8.00 (H, d), 7.60 (H, t), 7.50 (H, t), 5.30 (H, d) 4.50-4. 35 (3H, m), 4.30-4. 25 (2H, m) ; 8 31p (162MHz, D20)-7. 0 (d, Jp-p = 19Hz), -10.1 (d, Jp-p = 20Hz),-21. 3 (t, Jpp=20Hz) ; m/z 506 (M-1).

Example 2 (2R3St4Re5R)-3t4-DihYdroxv-5-(5-trifluoromethVl-benzothiazol -2-vl)- tetrahvdrofuran-2-vimethvl triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 4 (163mg), proton sponge (156mg) and phosphorous oxychloride (0. 050mi) in trimethyl phosphate (1. 9ml), then tributylamine (0. 49mi) and 0.5M tributylammonium pyrophosphate in DMF (4. 9mi). The reaction was quenched with aqueous ammonium bicarbonate (122mg in 12ml of water) and stirred for 1.5h. Purification as for Example 1 gave the title compound as a white solid (30mg). 8H (400MHz, D20) 8.35 (H, s), 8.25 (H, d), 7.80 (H, d), 5.30 (H, d), 4.55-4. 40 (3H, m), 4.30-4. 25 (2H, m); 6 31p (162mHz, D2O) -6. 0 (d, Jp p = 20Hz), -9. 9 (d, Jp-p = 20Hz), -21. 1 (t, JP-P = 20Hz); m/z 574 (M-1).

Example 3 (2R,3S,4R,5R)-3,4-Dihydroxy-5-(6-chlorobenzothiazol-2-yl)- tetrahvdrofuran-2-vlmethvl triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 14 (155mg), proton sponge (165mg) and phosphorous oxychloride (0. 053ml) in trimethyl phosphate (2. 0ml), then tributylamine (0. 51 ml) and 0.5M tributylammonium pyrophosphate in DMF (5. 1 ml). The reaction was quenched with aqueous ammonium bicarbonate (129mg in 13ml of water) and stirred for 2h. Purification as for Example 1 gave the title compound as a white solid (30mg). 8H (400MHz, D2O) 8.15 (H, s), 7.95 (H, d), 7.60 (H, d), 5.25 (H, d), 4.50-4. 45 (2H, m), 4.40-4. 35 (H, m), 4.30-4. 25 (2H, m) ; 8 31p (162mHz, D2O) -5. 8--6.1 (m), -10.0 (d, Jp-p= 20Hz), -21.2 (t, Jp-p= 20Hz); m/z 540 (M-1).

Example 4 (2R3Sw4R5R)-3t4-Dihvdroxy-5-(6-methoxybenzothiazol-2-yl)- tetrahydrofuran-2-ylmethyl triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 15 (53mg), proton sponge (57mg) and phosphorous oxychloride (0. 018ml) in trimethyl phosphate (0. 8ml), then tributylamine (0. 21 ml) and 0.5M tributylammonium pyrophosphate in DMF (1. 79moi). The reaction was quenched with aqueous ammonium bicarbonate (44mg in 4. 5m ! of water).

Purification as for Example 1 gave the title compound as a colourless gum (30mg). 8H (400MHz, D20) 7.90 (H, d), 7.65 (H, s), 7.20 (H, d), 5.25 (H, d), 4.50-4. 40 (2H, m), 4.40-4. 35 (H, m), 4.30-4. 25 (2H, m) ; 6 31p (162mHz, D20) -7. 8 (d, Jp-p = 19Hz),-10. 1 (d, Jp-p = 20Hz),-21. 5 (t, Jp-p = 20Hz) ; m/z 536 (M-1).

Example 5 (2R,3S,4R,5R)-3,4-Dihydroxy-5-(4-methoxy-benzothiazol-2-yl)- tetrahvdrofuran-2-vlmethvl triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 16 (118mg), proton sponge (127. 5mg) and phosphorous oxychloride (0. 041ml) in trimethyl phosphate (1. 6ml), then tributylamine (0. 40mi) and 0. 5M tributylammonium pyrophosphate in DMF (4. 0ml). The reaction was

quenched with aqueous ammonium bicarbonate (99mg in 10ml of water).

Purification as for Example 1 gave the title compound as a white solid (14.9mg). 8H (400MHz, D20) 7.70 (H, d), 7.45 (H, t), 7.15 (H, d), 5.25 (H, d), 4.5-4. 4 (2H, m), 4.4-4. 35 (H, m), 4.3-4. 2 (2H, m), 4.0 (3H, s) ; 8 31P (162mHz, D20)-5. 2 (d, Jp-p = 21 Hz),-9. 9 (d, Jp-p = 20Hz), -20. 8 (t, Jp-p = 20Hz) m/z 536 (M-1).

Example 6 (2R, 3S,4R,5R)-3,4-Dihydroxy-5-(5-fluorobenzothiazol-2-yl)- tetrahvdrofuran-2-vlmethvl triphosphate fris-triethvlammonium salt Prepared following the procedure for Example 1 from Intermediate 17 (62mg), proton sponge (70mg) and phosphorous oxychloride (0. 022mi) in trimethyl phosphate (1 ml), then tributylamine (0. 22ml) and 0.5M tributylammonium pyrophosphate in DMF (2. 2moi). The reaction was quenched with aqueous ammonium bicarbonate (54mg in 5ml of water) and stirred for 0.5h. Purification as for Example 1, but eluting the SPE cartridge with triethylamine instead of ammonia, gave the title compound as a white solid (30mg). 8H (400MHz, D2O) 8. 08 (H, dd), 7.74 (H, dd), 7.34 (H, t of d), 5.28 (H, d), 4.50-4. 36 (3H, m), 4.32-4. 24 (2H, m), 3.20 (18H, q) and 1.26 (27H, t); X 31p (162MHz, D2O) -8. 1 (d, Jp-p = 19.5Hz),-10. 1 (d, JP-P = 19.5Hz) and-21.5 (t, JP-P = 19.5Hz) ; m/z 524 (M-1).

Example 7 (2R, 3S, 4R, 5R)-5- (6-Chloro-4-fluorobenzothiazol-2-vl)-3, 4-dihvdroxv- tetrahydrofuran-2-ylmethyl triphosphate tris-triethylammonium salt Prepared following the procedure for Example 1 from Intermediate 18 (59mg), proton sponge (59mg) and phosphorous oxychloride (0. 019ml) in trimethyl phosphate (1 ml), then tributylamine (0. 18ml) and 0.5M tributylammonium pyrophosphate in DMF (1. 8mi). The reaction was quenched with aqueous ammonium bicarbonate (46mg in 5ml of water) and stirred for 0.5h. Purification as for Example 1, but eluting the SPE cartridge with triethylamine instead of ammonia, gave the title compound as a white solid (14mg). SH (400MHz, D20) 7.94 (H, s), 7.40 (H, d), 5. 28 (H, d), 4.50- 4.38 (3H, m), 4.30-4. 24 (2H, m), 3.20 (18H, q) and 1.28 (27H, t); 6 31p

(162MHz, D2O)-7. 5 (d, JP-P = 20Hz), -10. 1 (d, JP-P = 20Hz) and-21.5 (t, JP-P = 20Hz); m/z 558 (M-1).

Example 8 (2R3S4R5S)-2-Hvdroxymethyl-5"methyl-1 H-benzoimidazol-2-vl)- tetrahvdro-furan-3d4-diol triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 13 (72mg), proton sponge (87mg) and phosphorous oxychloride (0. 027ml) in trimethyl phosphate (1. 2ml), then tributylamine (0. 32ml) and 0.5M tributylammonium pyrophosphate in DMF (2. 73moi). The reaction was quenched with aqueous ammonium bicarbonate (68mg in 6. 8ml of water) and stirred for 0.5h. Purification as for Example 1 gave the title compound as a white solid (9mg). 6H (400MHz, D2O) 7.80 (H, d), 7.70 (H, d), 7.50-7. 40 (2H, m), 5.25 (H, d), 4.70 (H, t), 4.50 (H, t), 4.40 (H, d), 4.20 (2H, m), 4.00 (3H, s) ; # 31 (162MHz, D2O)-7. 3 (m), -9. 7 (d, JP-P = 19Hz) and-20.8 (t, Jp- p = 19Hz); m/z 503 (M-1).

Example 9 (2R, 3S, 4R, 5R)-2-Hvdroxvmethvl-5- (5-methvl-benzooxazol-2-yl)- tetrahvdro-furan-3, 4-diol triphosphate tris-ammonium salt Prepared following the procedure for Example 1 from Intermediate 19 (145mg), proton sponge (156mg) and phosphorous oxychloride (0. 056ml) in trimethyl phosphate (2. 2ml), then tributylamine (0. 55ml) and 0.5M tributylammonium pyrophosphate in DMF (5. 5ml). The reaction was quenched with aqueous ammonium bicarbonate (137mg in 14ml of water) and stirred for 1.5h. Purification as for Example 1 gave the title compound as a white gum (20mg). 8H (400MHz, D20) 7.60 (2H, m), 7.35 (H, d), 5.25 (H, d), 4.70 (H, t), 4.50 (H, t), 4.40 (H, m), 4.20 (2H, m), 2.45 (3H, s) ; 6 31p (162mHz, D20)-4. 8 (d, JP-P = 20Hz), -9.6 (d, Jp-p = 19Hz),-20. 3 (m); m/z 504 (M-1).

The following assays can be used to demonstrate the potency and selectivity of the compounds according to the invention.

P2Y2 Assay The P2Y2 clone was isolated from placental cDNA by PCR, using specific primers, inserted between the Not1 and EcoR1 sites in the multi-cloning site of the pIRESpuro vector (Clontech). The vector was stably transfected into a human astrocytoma cell-line, 1321 N1, and raised under puromycin selection.

The cells were maintained in Dulbecco's MEM growth medium, containing 10% fcs, 2mM glutamin, 1% non-essential amino acids, 2, ug/ml puromycin, at 37°C with 5% C02 and grown to sub-confluence, before removing with trypsin and re-seeding. Prior to assay, cells were seeded at 1 x 104 cells/well in 100tl of growth medium in a 96-well black walled, clear bottomed tissue culture plate and incubated at 37°C overnight.

The culture medium was gently removed from the wells and replaced with wash buffer (Hank's Balanced Salts Solution with 0.2% BSA and 20mM HEPES pH 7.2) containing 2, uM Fluo-4 and 0.02% pluronic acid. The plate was incubated at 37°C for 1 hour, then gently washed twice and 100 RI wash buffer added per well.

The calcium response assay was performed in a FLIPRTM (Molecular Devices). The compound of the invention was dissolved in DMSO and then diluted in wash buffer to give a DMSO concentration of 0.3% (reduced to 0.1% when added to the assay plate in the FLIP). The compound was added to the assay plate after a 10 second baseline. After a further 3 minutes a UTP stimulus was added. The response of the compound was compared to that of UTP.

Human P2Y4 receptors were cloned from genomic DNA by PCR, whilst P2Y6 receptors were isolated from a human peripheral blood mononuclear cell cDNA library. These receptors were stably expressed in 1321N1 cells and assayed as described above for P2Y2 receptors. In the above assays the preferred compound of the invention generally has EC50 values in the P2Y2, P2Y6 and/or P2Y4 assays of 10µM and below.