L-tartrate salt of ΛM-Adamantyl-2-(3-r(2fl>-2-(U2fl)-2-hvdroxy-2-r4-hvdroxy -3- (hvdroxymethyl)phenyllethyl)amino)propyn phenvDacetamide

This invention relates to the L-tartrate salt of Λ/-1-Adamantyl-2-{3-[(2fl)-2-({(2fl)-2- hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phenyl]ethyl}amino)pro pyl] phenyljacetamide and to processes for the preparation of, intermediates used in the preparation of, compositions containing and the uses of, said compound.

The invention also relates to the derived forms of the L-tartrate salt of Λ/-1-Adamantyl-2-{3-[(2f?)- 2-({(2/ ^: ?)-2-hydroxy-2-[4-hydroxy-3-(hydroxymethyl) phenyl]ethyl}amino)propyl]phenyl}acetamide, including hydrates, solvates and polymorphs thereof.

Adrenoceptors are members of the large G-protein coupled receptor super-family. The adrenoceptor subfamily is itself divided into the α and β subfamilies with the β sub-family being composed of at least 3 receptor sub-types: β1 , β2 and β3. These receptors exhibit differential expression patterns in tissues of various systems and organs of mammals. β2 adrenergic (β2) receptors are mainly expressed in smooth muscle cells (e.g. vascular, bronchial, uterine or intestinal smooth muscles), whereas β3 adrenergic receptors are mainly expressed in fat tissues (therefore β3 agonists could potentially be useful in the treatment of obesity and diabetes) and β1 adrenergic receptors are mainly expressed in cardiac tissues (therefore β1 agonists are mainly used as cardiac stimulants).

The pathophysiology and treatments of airway diseases have been extensively reviewed in the literature (for reference see Barnes, P.J. Chest, 1997, 111 :2, pp 17S-26S and Bryan, S.A. et al, Expert Opinion on investigational drugs, 2000, 9:1 , pp25-42) and therefore only a brief summary will be included here to provide some background information.

Glucocorticosteroids, anti-leukotrienes, theophylline, cromones, anti-cholinergics and β2 agonists constitute drug classes that are currently used to treat allergic and non-allergic airways diseases such as asthma and chronic obstructive airways disease (COPD). Treatment guidelines for these diseases include both short and long acting inhaled β2 agonists. Short acting, rapid onset β2 agonists are used for "rescue" bronchodilation, whereas, long-acting forms provide sustained relief and are used as maintenance therapy.

Bronchodilation is mediated via agonism of the β2 adrenoceptor expressed on airway smooth muscle cells, which results in relaxation and hence bronchodilation. Thus, as functional antagonists, β2 agonists can prevent and reverse the effects of all bronchoconstrictor substances, including leukothene D4 (LTD4), acetylcholine, bradykinin, prostaglandins, histamine and endothelins. Because β2 receptors are so widely distributed in the airway, β2

agonists may also affect other types of cells that play a role in asthma. For example, it has been reported that β2 agonists may stabilize mast cells. The inhibition of the release of bronchoconstrictor substances may be how β2 agonists block the bronchoconstriction induced by allergens, exercise and cold air. Furthermore, β2 agonists inhibit cholinergic neurotransmission in the human airway, which can result in reduced cholinergic-reflex bronchoconstriction .

In addition to the airways, it has also been established that β2 adrenoceptors are also expressed in other organs and tissues and thus β2 agonists, such as those described in the present invention, may have application in the treatment of other diseases such as, but not limited to those of the nervous system, premature labor, congestive heart failure, depression, inflammatory and allergic skin diseases, psoriasis, proliferative skin diseases, glaucoma and in conditions where there is an advantage in lowering gastric acidity, particularly in gastric and peptic ulceration.

However, numerous β2 agonists are limited in their use due to their low selectivity or adverse side-effects driven by high systemic exposure and mainly mediated through action at β2 adrenoreceptors expressed outside the airways (muscle tremor, tachycardia, palpitations, restlessness). Therefore there is a need for improved agents in this class.

Accordingly, there is still a need for novel β2 agonists that would have an appropriate pharmacological profile, for example in terms of potency, selectivity, duration of action and/or pharmacodynamic properties. In this context, the present invention relates to a novel beta 2 agonist.

The invention relates to the L-tartrate salt of Λ/-1-Adamantyl-2-{3-[(2fl)-2-({(2fl)-2- hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phenyl]ethyl}amino)pro pyl] phenyljacetamide and its derived forms.

It has now been found that the the L-tartrate salt of the invention is an agonist of the β2 receptors, that is particularly useful for the treatment of β2-mediated diseases and/or conditions, and show good potency, in particular when administered via the inhalation route.

The L-tartrate salt of the invention is particularly suitable for an administration by the inhalation route. In particular, the L-tartrate salt of the invention can be formulated for an administration using a dry powder inhaler.

The L-tartrate salt of the invention exhibits properties including those of solid state stability and compatibility with certain drug product excipient that render it superior to its corresponding free base.

Figure 1 represents the observed X-ray diffraction pattern of the L-tartrate salt of Λ/-1- Adamantyl-2-{3-[(2R)-2-({(2f?)-2-hydroxy-2-[4-hydroxy-3-(hyd roxymethyl) phenyl]ethyl}amino)propyl] phenyljacetamide.

The L-tartrate salt of the invention may be prepared from Λ/-1 -Adamantyl-2-{3-[(2fl)-2-

({(2fl)-2-hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phenyl]et hyl) amino) propyl]phenyl}acetamide according to conventional processes for the preparation of salts such as those disclosed in

"Handbook of Pharmaceutical Salts, Properties, Selection and Use. Published by Wiley-VCH, 2002. Edited by P. Heinrich Stahl, Camille G Wermuth. ISBN 3-906390-26-8".

The L-tartrate salt of Λ/-1 -Adamantyl-2-{3-[(2f?)-2-({(2f?)-2-hydroxy-2-[4-hydroxy-3- (hydroxymethyl)phenyl]ethyl}amino)propyl]phenyl}acetamide may exist in both unsolvated and solvated forms. The term 'solvate' is used herein to describe a molecular complex comprising the L-tartrate salt of the invention and a stoichiometric amount of one or more pharmaceutically acceptable solvent molecules, for example, ethanol. The term 'hydrate' is employed when said solvent is water.

Included within the scope of the invention are complexes such as clathrates, drug-host inclusion complexes wherein, in contrast to the aforementioned solvates, the drug and host are present in stoichiometric or non-stoichiomethc amounts. Also included are complexes of the drug containing two or more organic and/or inorganic components which may be in stoichiometric or non-stoichiomethc amounts. The resulting complexes may be ionised, partially ionised, or non- ionised. For a review of such complexes, see J Pharm Sci, 64 (8), 1269-1288 by Haleblian (August 1975).

Polymorphs and crystal morphologies/habits of the L-tartrate salt of the invention are also included within the scope of the invention.

The term "L-tartrate salt of the invention" include the L-tartrate salt of Λ/-1 -Adamantyl-2-{3-[(2/ ^: ?)- 2-({(2fl)-2-hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phenyl] ethyljamino) propyl]phenyl}acetamide and its derived forms.

The L-tartrate salt of the invention is a valuable pharmaceutically active compound, which is suitable for the therapy and prophylaxis of numerous disorders in which the β2 receptor is involved or in which agonism of this receptor may induce benefit, in particular the allergic and non-allergic airways diseases (e.g. asthma, COPD...) but also in the treatment of other diseases such as, but not limited to those of the nervous system, premature labor, congestive heart failure, depression, inflammatory and allergic skin diseases, psoriasis, proliferative skin

diseases, glaucoma and in conditions where there is an advantage in lowering gastric acidity, particularly in gastric and peptic ulceration.

The L-tartrate salt of the invention can be administered according to the invention to animals, preferably to mammals, and in particular to humans, as pharmaceutical for therapy and/or prophylaxis. It can be administered per se, in mixtures with one another or in the form of pharmaceutical preparations which as active constituent contain an efficacious dose of the L- tartrate salt of the invention, in addition to customary pharmaceutically innocuous excipients and/or additives.

The L-tartrate salt of the invention may be freeze-dried, spray-dried, or evaporatively dried to provide a solid plug, powder, or film of crystalline or amorphous material. Microwave or radio frequency drying may be used for this purpose.

The L-tartrate salt of the invention may be administered alone or in combination with other drugs and will generally be administered as a formulation in association with one or more pharmaceutically acceptable excipients. The term "excipient" is used herein to describe any ingredient other than the L-tartrate salt of the invention. The choice of excipient will to a large extent depend on the particular mode of administration.

The L-tartrate salt of the invention may be administered directly into the blood stream, into muscle, or into an internal organ. Suitable means for parenteral administration include intravenous, intraarterial, intraperitoneal, intrathecal, intraventricular, intraurethral, intrasternal, intracranial, intramuscular and subcutaneous. Suitable devices for parenteral administration include needle (including microneedle) injectors, needle-free injectors and infusion techniques.

Parenteral formulations are typically aqueous solutions which may contain excipients such as salts, carbohydrates and buffering agents (preferably to a pH of from 3 to 9), but, for some applications, they may be more suitably formulated as a sterile non-aqueous solution or as a dried form to be used in conjunction with a suitable vehicle such as sterile, pyrogen-free water.

The preparation of parenteral formulations under sterile conditions, for example, by lyophilisation, may readily be accomplished using standard pharmaceutical techniques well known to those skilled in the art.

Formulations for parenteral administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release. Thus the L-tartrate salt of the invention may be formulated as a solid, semi-solid, or thixotropic liquid for administration as an implanted depot providing

modified release of the active compound. .Examples of such formulations include drug-coated stents and PGLApoly(d/-lactic-coglycolic)acid (PGLA) microspheres.

The L-tartrate salt of the invention may also be administered topically to the skin or mucosa, that is, dermally or transdermally. Typical formulations for this purpose include gels, hydrogels, lotions, solutions, creams, ointments, dusting powders, dressings, foams, films, skin patches, wafers, implants, sponges, fibres, bandages and microemulsions. Liposomes may also be used.

Typical carriers include alcohol, water, mineral oil, liquid petrolatum, white petrolatum, glycerin, polyethylene glycol and propylene glycol. Penetration enhancers may be incorporated - see, for example, J Pharm Sci, 88 (10), 955-958 by Finnin and Morgan (October 1999).

Other means of topical administration include delivery by electroporation, iontophoresis, phonophoresis, sonophoresis and microneedle or needle-free (e.g. Powderject™, Bioject™, etc.) injection.

Formulations for topical administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.

The L-tartrate salt of the invention can also be administered intranasally or by inhalation, typically in the form of a dry powder (either alone, as a mixture, for example, in a dry blend with lactose, or as a mixed component particle, for example, mixed with phospholipids, such as phosphatidylcholine) from a dry powder inhaler or as an aerosol spray from a pressurised container, pump, spray, atomiser (preferably an atomiser using electrohydrodynamics to produce a fine mist), or nebuliser, with or without the use of a suitable propellant, such as 1 ,1 ,1 ,2-tetrafluoroethane or 1 ,1 ,1 ,2,3,3,3-heptafluoropropane. For intranasal use, the powder may comprise a bioadhesive agent, for example, chitosan or cyclodextrin.

The pressurised container, pump, spray, atomizer, or nebuliser contains a solution or suspension of the compound(s) of the invention comprising, for example, ethanol, aqueous ethanol, or a suitable alternative agent for dispersing, solubilising, or extending release of the active, a propellant(s) as solvent and an optional surfactant, such as sorbitan trioleate, oleic acid, or an oligolactic acid.

Prior to use in a dry powder or suspension formulation, the drug product is micronised to a size suitable for delivery by inhalation (typically less than 5 microns). This may be achieved by any appropriate comminuting method, such as spiral jet milling, fluid bed jet milling, supercritical fluid processing to form nanoparticles, high pressure homogenisation, or spray drying.

Capsules (made, for example, from gelatin or hydroxypropylmethylcellulose), blisters and cartridges for use in an inhaler or insufflator may be formulated to contain a powder mix of the L- tartrate salt of the invention, a suitable powder base such as lactose or starch and a performance modifier such as /-leucine, mannitol, or magnesium stearate. The lactose may be anhydrous or in the form of the monohydrate, preferably the latter. Other suitable excipients include dextran, glucose, maltose, sorbitol, xylitol, fructose, sucrose and trehalose.

A suitable solution formulation for use in an atomiser using electrohydrodynamics to produce a fine mist may contain from 1 μg to 20mg of the L-tartrate salt of the invention per actuation and the actuation volume may vary from 1 μl to 100μl. A typical formulation may comprise the L- tartrate salt of the invention, propylene glycol, sterile water, ethanol and sodium chloride. Alternative solvents which may be used instead of propylene glycol include glycerol and polyethylene glycol.

Suitable flavours, such as menthol and levomenthol, or sweeteners, such as saccharin or saccharin sodium, may be added to those formulations of the invention intended for inhaled/intranasal administration.

Formulations for inhaled/intranasal administration may be formulated to be immediate and/or modified release using, for example, PGLA. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.

In the case of dry powder inhalers and aerosols, the dosage unit is determined by means of a valve which delivers a metered amount. Units in accordance with the invention are typically arranged to administer a metered dose or "puff" containing from 0.001 mg to 10mg of the L-tartrate salt of the invention. The overall daily dose will typically be in the range 0.001 mg to 40mg which may be administered in a single dose or, more usually, as divided doses throughout the day.

The L-tartrate salt of the invention is particularly suitable for an administration by inhalation.

In particular, the L-tartrate salt of the invention is suitable for a formulation with lactose as a dry powder and can thus be administered using a dry powder inhaler.

The L-tartrate salt of the invention may be administered rectally or vaginally, for example, in the form of a suppository, pessary, or enema. Cocoa butter is a traditional suppository base, but various alternatives may be used as appropriate.

Formulations for rectal/vaginal administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.

The L-tartrate salt of the invention may also be administered directly to the eye or ear, typically in the form of drops of a micronised suspension or solution in isotonic, pH-adjusted, sterile saline. Other formulations suitable for ocular and aural administration include ointments, biodegradable (e.g. absorbable gel sponges, collagen) and non-biodegradable (e.g. silicone) implants, wafers, lenses and particulate or vesicular systems, such as niosomes or liposomes. A polymer such as crossed-linked polyacrylic acid, polyvinylalcohol, hyaluronic acid, a cellulosic polymer, for example, hydroxypropylmethylcellulose, hydroxyethylcellulose, or methyl cellulose, or a heteropolysaccharide polymer, for example, gelan gum, may be incorporated together with a preservative, such as benzalkonium chloride. Such formulations may also be delivered by iontophoresis.

Formulations for ocular/aural administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted, or programmed release.

The L-tartrate salt of the invention may be combined with soluble macromolecular entities, such as cyclodextrin and suitable derivatives thereof or polyethylene glycol-containing polymers, in order to improve their solubility, dissolution rate, taste-masking, bioavailability and/or stability for use in any of the aforementioned modes of administration.

Drug-cyclodextrin complexes, for example, are found to be generally useful for most dosage forms and administration routes. Both inclusion and non-inclusion complexes may be used. As an alternative to direct complexation with the drug, the cyclodextrin may be used as an auxiliary additive, i.e. as a carrier, diluent, or solubiliser. Most commonly used for these purposes are alpha-, beta- and gamma-cyclodextrins, examples of which may be found in International Patent Applications Nos. WO 91/11172, WO 94/02518 and WO 98/55148.

Inasmuch as it may desirable to administer a combination of active compounds, for example, for the purpose of treating a particular disease or condition, it is within the scope of the present invention that two or more pharmaceutical compositions, at least one of which contains the L- tartrate salt of the invention, may conveniently be combined in the form of a kit suitable for coadministration of the compositions.

Thus the kit of the invention comprises two or more separate pharmaceutical_compositions, at least one of which contains the L-tartrate salt of the invention in accordance with the invention,

and means for separately retaining said compositions, such as a container, divided bottle, or divided foil packet. An example of such a kit is the familiar blister pack used for the packaging of tablets, capsules and the like.

The kit of the invention is particularly suitable for administering different dosage forms, for example parenteral, for administering the separate compositions at different dosage intervals, or for titrating the separate compositions against one another. To assist compliance, the kit typically comprises directions for administration and may be provided with a so-called memory aid.

For administration to human patients, the total daily dose of the L-tartrate salt of the invention is typically in the range 0.001 mg to 5000mg depending, of course, on the mode of administration. For example, an intravenous daily dose may only require from 0.001 mg to 40mg. The total daily dose may be administered in single or divided doses_and may, at the physician's discretion, fall outside of the typical range given herein.

These dosages are based on an average human subject having a weight of about 65kg to 70kg. The physician will readily be able to determine doses for subjects whose weight falls outside this range, such as infants and the elderly.

For the avoidance of doubt, references herein to "treatment" include references to curative, palliative and prophylactic treatment.

According to another embodiment of the present invention, the L-tartrate salt of the invention or compositions thereof, can also be used as a combination with one or more additional therapeutic agents to be co-administered to a patient to obtain some particularly desired therapeutic end result such as the treatment of pathophysiologically-relevant disease processes including, but not limited to (i) bronchoconstriction, (ii) inflammation, (iii) allergy, (iv) tissue destruction, (v) signs and symptoms such as breathlessness, cough.

As used herein, the terms "co-administration", "co-administered" and "in combination with", referring to the L-tartrate salt of the invention and one or more other therapeutic agents, is intended to mean, and does refer to and include the following:

• simultaneous administration of such combination of L-tartrate salt of the invention and therapeutic agent(s) to a patient in need of treatment, when such components are formulated together into a single dosage form which releases said components at substantially the same time to said patient,

• substantially simultaneous administration of such combination of L-tartrate salt of the invention and therapeutic agent(s) to a patient in need of treatment, when such components are formulated apart from each other into separate dosage forms which are taken at substantially the same time by said patient, whereupon said components are released at substantially the same time to said patient,

• sequential administration of such combination of L-tartrate salt of the invention and therapeutic agent(s) to a patient in need of treatment, when such components are formulated apart from each other into separate dosage forms which are taken at consecutive times by said patient with a significant time interval between each administration, whereupon said components are released at substantially different times to said patient; and

• sequential administration of such combination of L-tartrate salt of the invention and therapeutic agent(s) to a patient in need of treatment, when such components are formulated together into a single dosage form which releases said components in a controlled manner whereupon they are concurrently, consecutively, and/or overlapingly administered at the same and/or different times by said patient,

where each part may be administered by either the same or different route.

Suitable examples of other therapeutic agents which may be used in combination with the L-tartrate salt of the invention, or pharmaceutically acceptable salts, derived forms or compositions thereof, include, but are by no means limited to:

(a) 5-Lipoxygenase (5-LO) inhibitors or 5-lipoxygenase activating protein (FLAP) antagonists,

(b) Leukotriene antagonists (LTRAs) including antagonists of LTB ₄ , LTC ₄ , LTD ₄ , and LTE ₄ ,

(c) Histamine receptor antagonists including H1 and H3 antagonists,

(d) a,- and (^-adrenoceptor agonist vasoconstrictor sympathomimetic agents for decongestant use,

(e) muscarinic M3 receptor antagonists or anticholinergic agents,

(f) PDE inhibitors, e.g. PDE3, PDE4 and PDE5 inhibitors,

(g) Theophylline,

(h) Sodium cromoglycate, (i) COX inhibitors both non-selective and selective COX-1 or COX-2 inhibitors (NSAIDs),

(j) Oral and inhaled glucocorticosteroids, such as DAGR (dissociated agonists of the corticoid receptor)

(k) Monoclonal antibodies active against endogenous inflammatory entities,

(I) Anti-tumor necrosis factor (anti-TNF-α) agents, (m) Adhesion molecule inhibitors including VLA-4 antagonists,

(n) Kinin-B, - and B ₂ -receptor antagonists,

(o) Immunosuppressive agents, (p) Inhibitors of matrix metalloproteases (MMPs), (q) Tachykinin NK ₁ , NK ₂ and NK ₃ receptor antagonists, (r) Elastase inhibitors, (s) Adenosine A2a receptor agonists, (t) Inhibitors of urokinase,

(u) Compounds that act on dopamine receptors, e.g. D2 agonists, (v) Modulators of the NFicβ pathway, e.g. IKK inhibitors,

(w) modulators of cytokine signalling pathways such as p38 MAP kinase, syk kinase or JAK kinase inhibitor,

(x) Agents that can be classed as mucolytics or anti-tussive, and (y) Antibiotics.

According to the present invention, combination of the L-tartrate salt of the invention with

- H3 antagonists,

- Muscarinic M3 receptor antagonists,

- PDE4 inhibitors,

- glucocorticosteroids,

- Adenosine A2a receptor agonists, - Modulators of cytokine signalling pathyways such as p38 MAP kinase or syk kinase, or,

- Leukotriene antagonists (LTRAs) including antagonists of LTB ₄ , LTC ₄ , LTD ₄ , and LTE ₄ , are preferred.

According to the present invention, combination of the L-tartrate salt of the invention with : glucocorticosteroids, in particular inhaled glucocorticosteroids with reduced systemic side effects, including prednisone, prednisolone, flunisolide, triamcinolone acetonide, beclomethasone dipropionate, budesonide, fluticasone propionate, ciclesonide, and mometasone furoate, or

- muscarinic M3 receptor antagonists or anticholinergic agents including in particular ipratropium salts, namely bromide, tiotropium salts, namely bromide, oxitropium salts, namely bromide, perenzepine, and telenzepine, are further preferred.

It is to be appreciated that all references herein to treatment include curative, palliative and prophylactic treatment. The description, which follows, concerns the therapeutic applications to which the L-tartrate salt of the invention may be put.

The L-tartrate salt of the invention has the ability to interact with the β2 receptor and thereby have a wide range of therapeutic applications, as described further below, because of the essential role which the β2 receptor plays in the physiology of all mammals.

Therefore, a further aspect of the present invention relates to the L-tartrate salt of the invention or compositions thereof, for use in the treatment of diseases, disorders, and conditions in which the β2 receptor is involved. More specifically, the present invention also concerns the L- tartrate salt of the invention or compositions thereof, for use in the treatment of diseases, disorders, and conditions selected from the group consisting of :

• asthma of whatever type, etiology, or pathogenesis, in particular asthma that is a member selected from the group consisting of atopic asthma, non-atopic asthma, allergic asthma, atopic bronchial IgE-mediated asthma, bronchial asthma, essential asthma, true asthma, intrinsic asthma caused by pathophysiologic disturbances, extrinsic asthma caused by environmental factors, essential asthma of unknown or inapparent cause, non-atopic asthma, bronchitic asthma, emphysematous asthma, exercise-induced asthma, allergen induced asthma, cold air induced asthma, occupational asthma, infective asthma caused by bacterial, fungal, protozoal, or viral infection, non-allergic asthma, incipient asthma, wheezy infant syndrome and bronchiolytis,

• chronic or acute bronchoconstriction, chronic bronchitis, small airways obstruction, and emphysema,

• obstructive or inflammatory airways diseases of whatever type, etiology, or pathogenesis, in particular an obstructive or inflammatory airways disease that is a member selected from the group consisting of chronic eosinophilic pneumonia, chronic obstructive pulmonary disease (COPD), COPD that includes chronic bronchitis, pulmonary emphysema or dyspnea associated or not associated with COPD, COPD that is characterized by irreversible, progressive airways obstruction, adult respiratory distress syndrome (ARDS), exacerbation of airways hyper-reactivity consequent to other drug therapy and airways disease that is associated with pulmonary hypertension,

• bronchitis of whatever type, etiology, or pathogenesis, in particular bronchitis that is a member selected from the group consisting of acute bronchitis, acute laryngotracheal bronchitis, arachidic bronchitis, catarrhal bronchitis, croupus bronchitis, dry bronchitis,

infectious asthmatic bronchitis, productive bronchitis, staphylococcus or streptococcal bronchitis and vesicular bronchitis,

• acute lung injury,

• bronchiectasis of whatever type, etiology, or pathogenesis, in particular bronchiectasis that is a member selected from the group consisting of cylindric bronchiectasis, sacculated bronchiectasis, fusiform bronchiectasis, capillary bronchiectasis, cystic bronchiectasis, dry bronchiectasis and follicular bronchiectasis.

A still further aspect of the present invention also relates to the use of the L-tartrate salt of the invention or compositions thereof, for the manufacture of a drug having a β2 agonist activity. In particular, the present inventions concerns the use of the L-tartrate salt of the invention, or pharmaceutically acceptable salts, derived forms or compositions thereof, for the manufacture of a drug for the treatment of β2-mediated diseases and/or conditions, in particular the diseases and/or conditions listed above.

As a consequence, the present invention provides a particularly interesting method to treat a mammal, including a human being, with an effective amount of the L-tartrate salt of the invention, or a composition thereof. More precisely, the present invention provides a particularly interesting method for the treatment of a β2-mediated diseases and/or conditions in a mammal, including a human being, in particular the diseases and/or conditions listed above, comprising admidministering said mammal with an effective amount of the L-tartrate salt of the invention.

Example 1

ΛM-Adamantyl-2-{3-[(2fl)-2-({(2fl)-2-hydroxy-2-[4-hydrox y-3- (hydroxymethyl)phenyl]ethyl}amino)propyl]phenyl}acetamide L-tartrate

A solution of Λ/-1 -adamantyl-2-{3-[(2R)-2-({(2R)-2-{[fert-butyl(dimethyl) silyl]oxy}-2-[4-hydroxy-3- hydroxymethyl)phenyl]ethyl}amino)propyl]phenyl} acetamide (preparation 1 ), (4.8g, 8mmol) in

tetrahydrofuran (5OmL) was added to triethylamine trihydrofluoride (1.3mL, 8mmol) and the mixture was stirred at room temperature for 24 hours. The reaction mixture was then concentrated in vacuo and the residue was purified by column chromatography on silica gel, eluting with dichloromethane:methanol:0.88 ammonia, 93:7:0.7, the appropriate fractions were concentrated in vacuo and the residue was dissolved in ethanol (2OmL). A suspension of L- tartaric acid (482mg, 3.2mmol) in ethanol (1OmL) was added and the mixture was cooled to - 2O ⁰ C for 18 hours. The reaction mixture was then warmed to room temperature and was triturated with pentane to give the crude compound (1.67g). A portion of the crude compound (1.31 g, 2.66mmol) was then re-crystallised from water, and dried under vacuum at 6O ⁰ C for 18 hours to afford the title compound as a crystalline solid (982mg)

¹ H NMR (400MHz, CD ₃ OD) δ: 7.35-7.14 (6H, m), 6.78 (1 H, d), 4.87 (1 H, t), 4.64 (2H, s), 4.39 (2H, s), 3.60-3.52 (1 H, m), 3.43 (2H, s), 3.20-3.12 (3H, m), 2.82-2.78 (1 H, m), 2.02 (3H, s), 2.00 (6H, s), 1.72-1.68 (6H, m), 1.25 (3H, d) ppm; Microanalysis: C ₃₀ H ₄₀ N ₂ O ₄ . C ₄ H ₆ O ₆ . 0.5 H ₂ O requires (%): C 62.66; H 7.27; N 4.30; found (%) C 62.56; H 7.37, N 4.13. [α] _D ²⁵ -16.75 (concentration: 1 mg/ml in MeOH)

The melting point of example 1 was determined by Differential Scanning Calorimetry (DSC) using a Perkin Elmer DSC7. The sample of example 1 (2.940 mg) was heated from 30-300 ⁰ C at 20°C/min in a nitrogen atmosphere. The material was sealed into a vented aluminium pan. The melting point was evidenced by a strong endotherm at 194°C (onset at 187°C). Post-melt endothermic degradation events were also observed.

The powder X-ray diffraction pattern of the L-tartrate salt of Λ/-1 -Adamantyl-2-{3-[(2fl)-2-({(2fl)- 2-hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phenyl]ethyl}amino) propyl]phenyl}acetamide was obtained using a Bruker D4 diffractometer (λ = 1.54178A) over the 2Θ angular range 2-55° with a 0.02° step size. Data was collected at each step for 5 seconds. Peak positions were calibrated by use of silicon powder (15% wt.) as an internal reference standard (aligned to peaks at 2Θ = 28.4, 47.3°). Resultant powder X-ray diffraction pattern with intensities and peaks location (angle 2Θ error is +/- 0.1 degrees) are shown in the table below.

Angle Intensity % Angle Intensity % Angle Intensity %

2-Theta 2-Theta 2-Theta

8.3 21.6 22.8 19.4 31.8 10.8

9.1 13.4 23.5 10.5 32.3 10.3

14.9 43.7 24.3 22.2 33.6 10.8

15.6 17.5 24.7 13.5 34.3 12.6

16.5 13.3 25.1 18.9 35.7 12.8

16.7 36.2 25.5 13.4 36.2 16.8

17.0 26.3 25.9 15.1 38.0 12.8

17.1 25.3 26.2 12.5 38.8 11.3

18.3 100.0 27.1 13.1 39.7 12.3

19.1 26.6 27.6 10.8 40.2 12.2

19.8 23.1 30.0 14.7 41.1 10.8

20.6 36.7 30.7 15.0 42.8 13.3

20.9 78.4 31.5 10.9 43.5 11.1

The powder X-ray diffraction peaks representative of the L-tartrate salt of Λ/-1 -Adamantyl-2-{3- [(2fl)-2-({(2R)-2-hydroxy-2-[4-hydroxy-3-(hydroxymethyl)phen yl] ethyl}amino)propyl] phenyljacetamide are shown in table 2 below.

Angle 2-Theta

14.9

16.7

18.3

19.1

20.6

20.9

Preparation 1 : Λf-1-adamantyl-2-{3-[(2R)-2-({(2R)-2-{[ferf-butyl(dimethyl) silyl]oxy}-2-[4- hydroxy-3-(hydroxymethyl)phenyl]ethyl}amino)propyl]phenyl}ac etamide

A solution of (3-{(2R)-2-[(2f?)-2-{[te/t-butyl(dimethyl)silyl]oxy}-2-(4-hy droxy-3-hydroxymethyl- phenyl)-ethylamino]-propyl}-phenyl)-acetic acid (Preparation 2) (250mg, 0.45mmol), 1 -(3- dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (94mg, 0.49mmol), hydroxybenzotriazole monohydrate (66mg, 0.49mmol) in Λ/,/V-dimethylformamide (4ml) was treated with triethylamine (0.12ml, 0.89mmol) and adamantan-1 -ylamine (75mg, O.SOmmol) and the resulting suspension left to stir at room temperature under a nitrogen atmosphere for 18 hours. The solvent was removed in vacuo and the residue partitioned between ethyl acetate (10ml) and saturated aqueous sodium bicarbonate (10ml). The organic phase was separated, and the aqueous phase extracted with further ethyl acetate (2x1 OmI). The combined organic extracts were washed with water (5ml), brine (5ml), dried (sodium sulfate) and the solvent removed in vacuo. The residue was purified by flash column chromatography on silica gel

eluting with dichloromethane:methanol: 880 ammonia (95:5:0.5 by volume) to give the title compound as a white foam. (50mg).

¹ H NMR (400MHz, CD ₃ OD): δ = 7.20-6.93 (6H, m), 6.68-6.65 (1 H, d), 4.74-4.68 (1 H, m), 4.65-

4.58 (2H, m), 3.40 (s, 2H), 2.96-2.85 (m, 2H), 2.72-2.54 (3H, m), 2.04 (3H, s), 2.01 (6H, s), 1.70

(6H, s), 1.07-1.05 (3H, d), 0.85 (9H, s), 0.02 (3H, s), -0.19 (3H, s) ppm.

LRMS (electrospray) : m/z [M-H] ^' 605.

Preparation 2: (3-{(2fl)-2-[(2fl)-2-{[tert-Butyl(dimethyl)silyl]oxy}-2-(4-h ydroxy-3- hydroxymethyl-phenyl)-ethylamino]-propyl}-phenyl)-acetic acid

A solution of methyl (3-{(2fl)-2-[(2fl)-2-{[fert-butyl(dimethyl)silyl]oxy}-2-(4-h ydroxy-3- hydroxymethy1-phenyl)-ethylamino]-propyl}-phenyl)-acetate (Preparation 3) (7.04g, 14.43mmol) in tetrahydrofuran (40ml) was treated with lithium hydroxide (28.9ml of a 1 M aqueous solution, 28.9mmol) and the reaction left to stir at room temperature for 16 hours. Hydrochloric acid (28.9ml of a 1 M aqueous solution, 28.9mmol) was added and then the tetrahydrofuran was removed in vacuo. The remaining aqueous layer was decanted and the residue washed with further water (10ml). The residue was redisolved in methanol (30ml) and the solvent removed in vacuo to give the title compound as a colorless foam (5.95g) which was used without further purification.

¹ H NMR (400MHz, CD ₃ OD): δ = 7.32 (1 H, s), 7.25-7.18 (2H, m), 7.13 (1 H, s), 7.12-7.10 (1 H, d), 7.02-7.01 (1 H, d), 6.79-6.77 (1 H, d), 4.98-4.95 (1 H, m), 4.65-4.64 (2H, d), 3.48 (2H, s), 3.48- 3.43 (1 H, m), 3.28-3.23 (1 H, dd), 3.13-3.09 (1 H, dd), 2.98-2.93 (1 H, dd), 2.77-2.72 (1 H, dd), 1.23-1.21 (3H, d), 0.86 (9H, s), 0.06 (3H, s), -0.13 (3H, s) ppm. LRMS (electrospray) : m/z [M+H] ⁺ 474, [M+Na] ⁺ 496, [M-H] ^" 472.

CHN analysis : found C 64.15%, H 8.25%, N 2.84%; C ₂₆ H ₃₉ NO ₅ Si+0.7H ₂ O requires C 64.22%, H 8.37%, N 2.88%.

Preparation 3: methyl (3-{(2fl)-2-[(2fl)-2-{[tert-butyl(dimethyl)silyl]oxy}-2-(4-h ydroxy-3- hydroxymethyl-phenyl)-ethylamino]-propyl}-phenyl)-acetate

A suspension of methyl (3-{(2fl)-2-[(2/ ^: ?)-2-{[tert-butyl(climethyl)silyl]oxy}-2-(4-[benzyloxy ]-3- hydroxymethyl-phenyl)-ethylamino]-propyl}-phenyl)-acetate (Preparation 4) (5.27g, 9.12mmol) and 10% palladium on carbon (1.0Og) in ethanol (50ml) was stirred under an atmosphere of hydrogen (60psi) at room temperature for 16 hours. The catalyst was filtered off through arbocel and the filtrate concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with dichloromethane:methanol:880 ammonia (96:4:0.4 changing to 95:5:0.5, by volume) to give the title compound as a pale yellow oil (1.99g) which was used without further purification. ¹ H NMR (400MHz, CD ₃ OD): δ = 7.21 -7.17 (2H, m), 7.11 -7.09 (1 H, d), 7.03-6.98 (3H, m), 6.69- 6.67 (1 H, d), 4.71 -4.68 (1 H, t), 4.62-4.61 (2H, d), 3.67 (3H, s), 3.59 (2H, s), 2.96-2.86 (2H, m), 2.69-2.55 (3H, m), 1.07-1.05 (3H, d), 0.82 (9H, s), -0.01 (3H, s), -0.20 (3H, s) ppm. LRMS (electrospray) : m/z [M+H] ⁺ 488, [M+Na] ⁺ 510, [M-H] ^" 486

Preparation 4: methyl (3-{(2fl)-2-[(2fl)-2-{[fert-butyl(dimethyl)silyl]oxy}-2-(4-[ benzyloxy]-3- hydroxymethyl-phenyl)-ethylamino]-propyl}-phenyl)-acetate

A solution of [2-(benzyloxy)-5-((1 R)-2-bromo-1 -{[fert-butyl(dimethyl) silyl]oxy}ethyl) phenyl]methanol (Preparation 5) (12.5g, 27.7mmol) and methyl [3-[(2R)-2- aminopropyl]phenyl}acetate (Preparation 7) (11.5g, 55.4mmol) in dichloromethane (130ml) was heated to 9O ⁰ C, allowing the dichloromethane to evaporate. The resulting melt was left at 90°C for a further 16 hours. The reaction mixture was cooled to room temperature and purified by flash column chromatography on silica gel eluting with dichloromethane:methanol:880 ammonia (98:2:0.2 changing to 97:3:0.3, by volume) to give the title compound (12.1g) as a white oil. ¹ H NMR (400MHz, CD ₃ OD): δ = 7.47-7.45 (2H, m), 7.39-7.29 (4H, m), 7.19-7.15 (1 H, t), 7.13- 7.07 (2H, m), 7.03 (1 H, s), 7.01 -6.99 (1 H, d), 6.93-6.91 (1 H, d), 5.12 (2H, s), 4.76-4.73 (1 H, t),

4.67-4.66 (2H, d), 3.66 (3H, s), 3.58 (2H, s), 2.95-2.80 (2H, m), 2.68-2.55 (3H ₁ m), 1.06-1.05 (3H, d), 0.83 (9H, s), 0.00 (3H, s), -0.19 (3H, s) ppm. LRMS (electrospray) : m/z [M+H] ⁺ 578, [M+Na] ⁺ 600.

Preparation 5: [2-(benzyloxy)-5-((1 /7)-2-bromo-1-{[tert-butyl(dimethyl) silyl]oxy}ethyl) phenyl]methanol

Borane dimethylsulfide complex (42.4ml of 10M solution in tetrahydrofuran, 424mmol) was added dropwise to a solution of methyl 2-(benzyloxy)-5-((1 / ^: ?)-2-bromo-1 -{[fert- butyl(dimethyl)silyl]oxy}ethyl)benzoate (Preparation 6), (91.Og, 189mmol) in tetrahydrofuran (1600ml). The resulting mixture was then heated to reflux for 2 hours and then cooled to 0 ⁰ C before quenching with methanol (270ml). The mixture was left to stir at room temperature for 16 hours and then the solvent removed in vacuo. The residue was partitioned between dichloromethane (500ml) and water (500ml). The aqueous phase was separated and extracted with dichloromethane (500ml) and the combined organic extracts washed with saturated aqueous sodium chloride (500ml), dried (magnesium sulfate) and the solvent removed in vacuo. The residue was purified by flash column chromatography on silica gel eluting with cyclohexane:ethyl acetate (100:0 changing to 80:20, by volume) to give the title compound (68.7g) as a colourless oil.

¹ H NMR (400MHz, CDCI ₃ ): δ = 7.42-7.36 (5H, m), 7.29-7.25 (3H, m), 6.94 (1 H, d), 5.12 (2H, s), 4.84-4.81 (1 H, m), 4.74 (2H, s), 3.48-3.40 (2H, m), 0.90 (9H, s), 0.11 (3H, s), -0.07 (3H, s) ppm. LRMS (electrospray) : m/z [M+Na] ⁺ 473 / 475.

Preparation 6: methyl 2-(benzyloxy)-5-((1 fl)-2-bromo-1 -{[fert-butyl

(dimethyl)silyl]oxy}ethyl)benzoate

A solution of methyl 2-(benzyloxy)-5-[(1 fl)-2-bromo-1 -hydroxyethyl]benzoate (71.05g, 195mmol), imidazole (18.52g, 272mmol), fert-butyldimethylsilyl chloride (32.23g, 214mmol) and 4-(N ₁ N- dimethylamino)pyridine (0.44g, 3.6mmol) in Λ/,Λ/-dimethylformamide (270ml) was left to stir at room temperature under a nitrogen atmosphere for a period of 24 hours. The solvent was removed in vacuo and the residue partitioned between ethyl acetate (500ml) and water (500ml). The organic phase was separated and washed with 2N hydrochloric acid (2-fold 500ml), saturated aqueous sodium bicarbonate (2-fold 500ml) saturated sodium chloride (500ml), dried (magnesium sulfate) and the solvent removed in vacuo to give the title compound as a colourless oil (91.Og). ¹ H NMR (400MHz, CDCI ₃ ): δ = 7.81 (1 H, bs), 7.51 -7.30 (6H, m), 7.01 (1 H, d), 5.19 (2H, s), 4.85- 4.82 (1 H, m), 3.91 (3H, s), 3.48-3.39 (2H, m), 0.90 (9H, s), 0.11 (3H, s), -0.08 (3H, s) ppm. LRMS (electrospray) : m/z [M+Na] ⁺ 501 / 503.

Preparation 7: methyl {3-[(2fl)-2-aminopropyl]phenyl}acetate

A solution of methyl [3-((2f?)-2-{[(1 / ^: ?)-1-phenyl-ethyl]-amino}-propyl)-phenyl]-acetate hydrochloride (Preparation 8) (7.69g, 22mmol) and ammonium formate (6.94g, 1 10mmol) was heated to 75°C in the presence of 20% palladium hydroxide-on-charcoal (Pd(OH) ₂ /C, 2.0Og). After 90 minutes the reaction mixture was cooled to room temperature, filtered through arbocel and the filtrate concentrated in vacuo. The residue was partitioned between dichloromethane (100ml) and 880 ammonia (100ml) and the organic phase separated. The aqueous phase was extracted dichloromethane (100ml) and the combined organic extracts dried (magnesium sulfate) and reduced in vacuo to give the title compound as a colourless oil (4.78g). ¹ H NMR (400MHz, CD ₃ OD): δ = 7.27-7.23 (1 H, t), 7.13-7.09 (3H, m), 3.67 (3H, s), 3.63 (2H, s), 3.12-3.05 (1 H, m), 2.67-2.57 (2H, m), 1.06 (3H, d) ppm. LRMS (electrospray) : m/z [MH-H] ⁺ 208, [M+Na] ⁺ 230.

Preparation 8: methyl [3-((2fl)-2-{[(1 ff)-1-phenyl-ethyl]-amino}-propyl)-phenyl]-acetate hydrochloride

A solution of methyl [3-(2-oxopropyl)phenyl]acetate (Preparation 9) (8.5g, 41.2mmol), (R)-a- methyl benzylamine (4.8ml, 37.2mmol), sodium thacetoxyborohydride (11.6g, 56mmol) and acetic acid (2.2ml, 38mmol) in dichloromethane (400ml) was stirred at room temperature for 48 hours. The reaction mixture was quenched by addition of saturated aqueous sodium bicarbonate (200ml) and allowed to stir until effervescence ceased. The organic phase was separated and the aqueous phase extracted with dichloromethane (100ml). The combined organic extracts were dried (magnesium sulfate) and reduced in vacuo. Purification by flash column chromatography eluting with dichloromethane:methanol: ammonia (99:1 :0.1 to 95:5:0.5 by volume) gave a 4:1 mixture of diastereomers (R,R major) as a pale yellow oil (8.71g). Treatment with hydrogen chloride (40ml of a 1 M solution in methanol, 40mmol) followed by three successive crystallisations (diisopropylether/ methanol) gave the title compound as a white crystalline solid (5.68g).

¹ H NMR (400MHz, CD ₃ OD): δ = 7.52-7.48 (5H, m), 7.28-7.25 (1 H, m), 7.18-7.16 (1 H, m), 7.02- 6.99 (2H, m), 4.59 (1 H, q), 3.62 (2H, s), 3.30 (3H, s), 3.30-3.25 (1 H, m), 3.26-3.15 (1 H, m), 2.66- 2.60 (1 H, m), 1.68 (3H, d), 1.18, (3H, d) ppm.

LRMS (electrospray): m/z [M+H] ⁺ 312, [M+Na] ⁺ 334.

Preparation 9: methyl [3-(2-oxopropyl)phenyl]acetate

Tributyltin methoxide (28.3 ml, 98mmol), preparation 10 (15.Og, 65mmol), isopropenyl acetate (10.8ml, 98mmol), palladium(ll)acetate (750mg, 3.30mmol) and tri-ortfto-tolylphosphine (2.Og, 6.5mmol) were stirred together in toluene (75ml) at 100 ⁰ C under nitrogen for 5 hours. After cooling the reaction was diluted with ethyl acetate (150ml) and 4M aqueous potassium fluoride solution (90ml) and stirred for 15 minutes. The mixture was filtered through arbocel and the organic phase separated and reduced In vacuo. The residue was purified by flash column chromatography silica gel eluting with a solvent gradient of diethyl ethenpentane (0:100 to 25:75, by volume) changing to dichloromethane to give the title compound as a pale yellow oil (12.6g). ¹ H NMR (400MHz, CDCI ₃ ): δ = 7.30 (1 H, t), 7.19 (1 H, d), 7.13-7.10 (2H, m), 3.69 (5H, s), 3.61 (2H, s), 2.15 (3H, s) ppm. LRMS (electrospray) : m/z [M+NH ₄ ] ⁺ 224, [M+Na] ⁺ 229.

Preparation 10: Methyl (3-bromophenyl)acetate

Acetyl chloride (0.7ml, 9.3mmol) was slowly added to a solution of (3-bromo-phenyl)-acetic acid (20.Og, 93mmol) in methanol (500ml) at O ⁰ C under nitrogen and the reaction was allowed to warm gradually to room temperature over a period of 5 hours. The solvent was removed in vacuo and the residual oil was redissolved in dichloromethane, dried (sodium sulfate) and concentrated in vacuo to give the title compound as a colourless oil (20.6g).

¹ H NMR (400MHz, CDCI ₃ ): δ = 7.37-7.45 (2H, m), 7.24-7.17 (2H, m), 3.70 (3H, s), 3.59 (2H, s) ppm.

LRMS (electrospray) : m/z [M+Na] ⁺ 253.

Abbreviations

TBDMS = fert-butyl(dimethyl)silyl

In vitro activity of the L-tartrate salt of the invention

The ability of the L-tartrate salt of the invention to act as potent β2 agonists therefore mediating smooth muscle relaxation may be determined by the measure of the effect of beta-2 adrenergic receptor stimulation on electrical field stimulated-contraction of guinea pig trachea strips.

Guinea-pig trachea

Male, Dunkin-Hartley guinea pigs (475-525g) are killed by CO ₂ asphyxiation and exsanguination from the femoral artery and the trachea is isolated. Four preparations are obtained from each animal, starting the dissection immediately below the larynx and taking 2.5 cm length of trachea. The piece of trachea is opened by cutting the cartilage opposite the trachealis muscle, then transverse sections, 3-4 cartilage rings wide, are cut. The resulting strip preparations are suspended in 5 ml organ baths using cotton threads tied through the upper and lower cartilage bands. The strips are equilibrated, un-tensioned, for 20 minutes in a modified Krebs Ringer buffer (Sigma K0507) containing 3 μM lndomethacin (Sigma I7378), 10 μM Guanethidine (Sigma G8520) and 10 μM Atenolol (Sigma A7655), heated at 37 ⁰ C and gassed with 95% O ₂ /5% CO ₂ , before applying an initial tension of 1 g. The preparations are allowed to equilibrate for a further 30-45 minutes, during which time they are re-tensioned (to 1 g) twice at 15-minute intervals. Changes in tension are recorded and monitored via standard isometric transducers coupled to a data-collection system (custom-designed at Pfizer). Following the tensioning equilibration, the tissues are subjected to electrical field stimulation (EFS) using the following parameters : 10 s trains every 2 minutes, 0.1 ms pulse width, 10 Hz and just-maximal voltage (25 Volts) continuously throughout the length of the experiment. EFS of post-ganglionic cholinergic nerves in the trachea results in monophasic contractions of the smooth muscle and twitch height is recorded. The organ baths are constantly perfused with the above-described Krebs Ringer buffer by means of a peristaltic pump system (pump flow rate 7.5 ml / minute) throughout the experiment, with the exception of when a beta-2 agonist according to the present invention is

added, the pump is then stopped for the time of the cumulative dosing to the bath and started again after maximal response is reached for the wash-out period.

Experimental protocol for assessment of potency and efficacy

Following equilibration to EFS, the peristaltic pump is stopped and the preparations 'primed' with a single dose of 300 nM isoprenaline (Sigma 15627) to establish a maximal response in terms of inhibition of the contractile EFS response. The isoprenaline is then washed out over a period of 40 minutes. Following the priming and wash-out recovery, a standard curve to isoprenaline is carried out on all tissues (Isoprenaline Curve 1) by means of cumulative, bolus addition to the bath using half log increments in concentration. The concentration range used is 1 ^e"9 to 1 ^θ /3 ^e"6 M. At the end of the isoprenaline curve the preparations are washed again for 40 minutes before commencing a second curve, either to isoprenaline (as internal control) or a beta-2 agonist according to the present invention. Beta-2 agonist responses are expressed as percentage inhibition of the EFS response. Data for beta-2 agonist are normalised by expressing inhibition as a percentage of the maximal inhibition induced by isoprenaline in Curve 1. The EC ₅₀ value for beta-2 agonist according to the present invention refers to the concentration of compound required to produce half maximal effect. Data for beta-2 agonists according to the present invention are then expressed as relative potency to isoprenaline defined by the ratio (EC ₅₀ beta- 2 agonist)/(EC50 Isoprenaline).

Confirmation of beta-2 mediated functional activity Beta-2 agonist activity of test compounds is confirmed using the protocol above, however, prior to constructing the curve to beta-2 agonist according to the present invention, the preparations are pre-incubated (for a minimum of 45 minutes) with 300 nM ICI 118551 (a selective β ₂ antagonist) which results in the case of a beta-2 mediated effect in a rightward-shift of the test compound dose response curve.

According to another alternative, the agonist potency for the β2 receptor of the L-tartrate salt of the invention may also be determined by the measure of the concentration of compound according to the present invention required to produce half maximal effect (EC ₅₀ ) for the β2 receptor.

Compound Preparation 10 mM/100% DMSO (dimethylsulfoxide) stock of compound is diluted to required top dose in 4 % DMSO. This top dose is used to construct a 10-point semi-log dilution curve, all in 4 % DMSO. Isoprenaline (Sigma, I-5627) was used as a standard in every experiment and for control wells on each plate. Data was expressed as % Isoprenaline response.

Cell Culture

CHO (Chinese Hamster Ovary) cells recombinantly expressing the human β2 adrenergic receptor (from Kobilka et al., PNAS 84: 46-50, 1987 and Bouvier et al., MoI Pharmacol 33: 133- 139 1988 CH0hβ2) were grown in Dulbeccos MEM/ NUT MIX F12 (Gibco, 21331-020) supplemented with 10 % foetal bovine serum (Sigma, F4135, Lot 90K8404 Exp 09/04), 2 mM glutamine (Sigma, G7513), 500 μg/ml geneticin (Sigma, G7034) and 10 μg/ml puromycin (Sigma, P8833). Cells were seeded to give about 90 % confluency for testing.

Assay Method

25 μl / well each dose of compound was transferred into a cAMP- Flashplate® (NEN, SMP004B), with 1% DMSO as basal controls and 100 nM lsoprenaline as max controls. This was diluted 1 :2 by the addition of 25 μl / well PBS. Cells were trypsinised (0.25% Sigma, T4049), washed with PBS (Gibco, 14040-174) and resuspended in stimulation buffer (NEN, SMP004B) to give 1x10 ⁶ cells / ml CHOhB2. Compounds were incubated with 50 μl / well cells for 1 hour. Cells were then lysed by the addition of 100 μl / well detection buffer (NEN, SMP004B) containing 0.18 μCi / ml ¹²⁵ I-CAMP (NEN, NEX-130) and plates were incubated at room temperature for a further 2 hours. The amount of ¹²⁵ I-CAMP bound to the Flashplate® was quantified using a Topcount NXT (Packard), normal counting efficiency for 1 minute. Dose- response data was expressed as % lsoprenaline activity and fitted using a four parameter sigmoid fit.

It has thus been found that the L-tartrate salt of example 1 show a β2 cAMP EC ₅₀ of 0.076 nM.