HK1156248A - Therapeutic uses of compounds having combined sert, 5-ht3, and 5-ht1a activity - Google Patents

Description

Having combined SERT, 5-HT3And 5-HT1ATherapeutic use of active compounds

Technical Field

The invention relates to SERT, 5-HT with a combination₃And 5-HT_1ATherapeutic use of the active compounds.

Background

Selective 5-hydroxytryptamine reuptake inhibitors (SSRIs) have been favored by physicians for many years for the treatment of many central nervous system disorders, such as depression and anxiety, because they are potent and have a good safety profile compared to the previous generation of central nervous system drugs, so-called tricyclic antidepressants. However, selective 5-hydroxytryptamine reuptake inhibitors are still limited to a significant fraction of non-responders, i.e., patients who do not respond to treatment or do not respond completely. Furthermore, SSRIs typically do not begin to show efficacy until several weeks after treatment. Finally, while SSRIs typically cause fewer adverse effects than tricyclic antidepressants, administration of SSRIs often associated with adverse effects, such as sexual side effects and sleep problems. These adverse effects are intolerable to many patients and result in mid-stream withdrawal of a significant fraction of patients receiving SSRI treatment.

It is known that the combined use of inhibiting the 5-hydroxytryptamine transporter (SERT) and activating one or more 5-hydroxytryptamine receptors is useful. The use of pindolol (a 5-HT) in combination has been reported_1APartial agonists) and 5-hydroxytryptamine reuptake inhibitors cause rapid onset of action [ psych. res., 125, 81-86, 2004]. This means a shorter onset of increased 5-hydroxytryptamine levels in the clinic and an increase or enhancement in the therapeutic effect of 5-hydroxytryptamine reuptake inhibitors.

Central nervous system related disorders such as, for example, depression, anxiety and schizophrenia are often co-morbid with other diseases or disorders such as cognitive deficits or cognitive disorders [ scand.j.psych., 43, 239-; am.J.Psych., 158, 1722-one 1725, 2001 ].

Several neurotransmitters are postulated to be involved in neuronal events that regulate cognition. In particular, the cholinergic system shows a significant role in cognition, and thus compounds affecting the cholinergic system have potential benefits for the treatment of cognitive disorders. Influencing 5-HT_1AReceptor and/or 5-HT₃Compounds of receptors are known to affect the cholinergic system, and they may be equally useful in the treatment of cognitive disorders.

Thus, exert 5-HT_1AReceptor and/or 5-HT₃Compounds that are receptor active are expected to be useful in the treatment of cognitive disorders. Compounds that additionally exert SERT activity would be particularly useful for the treatment of cognitive disorders in patients who also suffer from diseases that would benefit from a (faster) increase in 5-hydroxytryptamine levels.

The international application published as WO 03/029232 describes a series of compounds, including 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine (example 1e), having 5-hydroxytryptamine reuptake inhibitory activity.

International application WO2007/144005, published after the priority date of the present application, describes 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl]Piperazine is also 5-HT₃Antagonists and 5-HT_1AA partial agonist.

Summary of The Invention

The present inventors have surprisingly found that 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl]Piperazine exerts SERT inhibition, 5-HT₃Antagonism and 5-HT_1AA combination of agonism. Accordingly, the present invention provides a method for treating a disease comprising administering to a patient in need thereof a therapeutically effective amount of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl]Piperazine or a pharmaceutically acceptable salt thereof.

In one embodiment, the invention relates to the use of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine or a pharmaceutically acceptable salt thereof in the manufacture of a medicament for the treatment of a disease.

In one embodiment, the present invention provides 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine or a pharmaceutically acceptable salt thereof for use in the treatment of a disease.

Drawings

FIG. 1: XRPD of crystalline base

FIG. 2: XRPD of alpha-hydrobromide

FIG. 3: XRPD of hydrobromide form beta

FIG. 4: XRPD of gamma-form hydrobromide

FIG. 5: XRPD of hydrobromide hemihydrate

FIG. 6: the placebo, 5mg and 10mg compound I (HBr salt) groups evaluated the change in item 4 (Insomnia Early) for HAM-D over 6 weeks. Each group had about 100 patients

FIG. 7: placebo, 5mg and 10mg compound I (HBr salt) groups evaluated for changes in item 5 (Insomnia Middle) over 6 weeks of HAM-D. Each group had about 100 patients

FIG. 8: the placebo, 5mg and 10mg compound I (HBr salt) groups evaluated the change in item 6 (early wake (Insomnia Late)) by HAM-D over 6 weeks. Each group had about 100 patients

FIG. 9: effect of compound I in dermal formalin assay. The X-axis shows the amount of compound administered; the Y-axis shows the time (seconds) taken to lick the paw. FIG. 9 a: response over a period of 0-5 minutes; FIG. 9 b: response over a 20-30 minute period.

FIG. 10 a: levels of extracellular acetylcholine in the prefrontal cortex of free-moving rats upon administration of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine HBr salt

FIG. 10 b: extracellular acetylcholine levels in the ventral hippocampus of free-moving rats upon administration of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine HBr salt.

FIG. 11: effect of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine HBr salt on associative conditioned fear (contextual fear) in Sprague-Dawley rats when dosed 60 minutes prior to acquisition (acquisition). Catalepsy was scored (white bars) at the 58 second adaptation time (obtained before shock) prior to the foot shock US. The rigor behaviour (retention test) was measured 24h after training (black bars).

FIG. 12: effect of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine HBr salt on associative conditioned fear in Sprague-Dawley rats when dosed 1 hour prior to the retention test. The catalepsy was scored during 58 seconds before (obtained) the foot shock US (white bars). The stiff behaviour (retention test) was measured 24h after training (black bars).

FIG. 13: effect of HBr salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine on associative conditioned fear in Sprague-Dawley rats when administered immediately after acquisition. The catalepsy was scored during the 58 seconds prior to foot shock US (obtained before shock) (white bars). The stiff behaviour (retention test) was measured 24h after training (black bars).

Detailed Description

The invention relates to application of a compound I, namely 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof, wherein the structure of the compound is

In one embodiment, the pharmaceutically acceptable salt is a non-toxic acid addition salt. The salts include those formed from organic acids such as maleic acid, fumaric acid, benzoic acid, ascorbic acid, succinic acid, oxalic acid, dimethylene salicylic acid, methanesulfonic acid, ethane disulfonic acid, acetic acid, propionic acid, tartaric acid, salicylic acid, citric acid, gluconic acid, lactic acid, malic acid, mandelic acid, cinnamic acid, citraconic acid, aspartic acid, stearic acid, palmitic acid, itaconic acid, glycolic acid, p-aminobenzoic acid, glutamic acid, benzenesulfonic acid, theophylline acetic acid, and 8-halotheophyllines such as 8-bromotheophylline. The salts can also be made from inorganic salts such as hydrochloric acid, hydrobromic acid, sulfuric acid, sulfamic acid, phosphoric acid and nitric acid. Mention may in particular be made of the salts made of methanesulfonic acid, maleic acid, fumaric acid, meso-tartaric acid, (+) -tartaric acid, (-) -tartaric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, phosphorous acid and nitric acid. Reference is explicitly made to the hydrobromide salt.

In one embodiment, the invention relates to the use of said compound I, which is not 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine free base in amorphous form.

Oral dosage forms, particularly tablets, are generally preferred by patients and physicians for ease of administration and for better compliance thereby. For tablets, the active ingredient is preferably crystalline. In one embodiment, the present invention relates to the use of a compound in a crystalline form. The crystallinity of the compound used in the present invention was confirmed by XRDP in fig. 1 to 5. WO2007/144005 describes XRDP reflections of other salts used in the present invention. The following table summarizes the major XRDP reflections of certain compounds used in the present invention.

Selected X-ray peak position (° 2 θ), all values + -0.1 °

					Crystalline base	11.10	16.88	17.42	22.23
-hydrobromide salt (. alpha.)	5.85	9.30	17.49	18.58
					-hydrobromide salt (. beta.)	6.89	9.73	13.78	14.62
-hydrobromide salt (. gamma.)	11.82	16.01	17.22	18.84
					-hydrobromide salt (hydrate)	10.69	11.66	15.40	17.86

In one embodiment, the crystals used in the present invention are solvates, i.e. wherein the solvent molecules form part of the crystal structure. The solvate may be formed from water, in which case the solvate is commonly referred to as a hydrate. Alternatively, the solvate may be formed from other solvents such as, for example, ethanol, acetone or ethyl acetate. The exact amount of solvate will generally depend on a variety of conditions. For example, hydrates typically lose water when temperature is increased or when relative humidity is decreased.

In one embodiment, the compounds of the present invention are non-solvated crystals.

Certain compounds are hygroscopic, i.e., absorb water, when exposed to a humid environment. Hygroscopicity is generally considered as an undesirable property of compounds present in pharmaceutical formulations, in particular dry formulations such as tablets. In one embodiment, the present invention provides crystals having low hygroscopicity. For oral dosage forms using crystalline active ingredients, it is also advantageous if the crystals are well defined. In this context, the term "well-defined" especially means that the stoichiometry is well-defined, i.e. the ratio between the ions forming the salt is a ratio between small integers, such as 1: 1, 1: 2, 2: 1, 1: 1, etc. In one embodiment, the compounds of the invention are well-defined crystals.

The crystalline compounds used in the present invention may exist in more than one form, i.e. they may exist in polymorphic form. If a compound can exist in more than one form, polymorphic forms are formed. The present invention is intended to encompass all such polymorphic forms as pure compounds or mixtures thereof.

In one embodiment, the present invention uses the compound in a purified form. The term "purified form" means that the compound is substantially free of other compounds or other forms of the same compound, as the case may be.

For example, as demonstrated in figures 2-5, the compound used in the present invention (in this case, the hydrobromide salt) can exist in a variety of forms, i.e., polymorphs. The polymorphic forms have different properties, as shown in example 2. The beta hydrobromide salt was more stable as evidenced by the higher DSC melting point and lower solubility. Moreover, form β has an attractive combination of low hygroscopicity and solubility, which makes the compound particularly suitable for the preparation of tablets. Accordingly, in one embodiment, the invention provides the use of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenylpiperazine hydrobromide having XRDP reflections at about 6.89, 9.73, 13, 78 and 14.62(° 2 Θ), with a particular XRPD as shown in figure 3.

The solubility of the active ingredient is also very important for the choice of dosage form, since it has a direct influence on the bioavailability. For oral dosage forms, a higher solubility of the active ingredient is generally considered advantageous because it increases bioavailability.

As shown in example 1, in the present inventionThe compounds used in (1) are potent inhibitors of the human 5-hydroxytryptamine transporter, i.e. they inhibit 5-hydroxytryptamine reuptake. Furthermore, the compounds show 5-HT in mice, rats, guinea pigs and dogs₃Are potent antagonists at the receptor. Human 5-HT in cloning into oocytes₃At the receptor, the compounds were found to be antagonists (IC) at low concentrations₅₀About 20nM), whereas at high concentrations the compounds show agonistic properties (ED)₅₀2.1 μm). The compounds of the invention do not show any agonistic response at the high concentrations subsequently applied, which may be due to rapid desensitization or direct antagonism in vitro. Thus, as in other species 5-HT₃Observed on the receptor, 5-HT in humans₃The compounds of the invention show significant antagonism at low concentrations at the receptor. The data also show that the compounds used in the present invention are at 5-HT_1AAgonists at the receptor with a K of 15nM_iValue and 96% intrinsic activity (or efficacy). WO2007/144005 describes slightly different values. However, this difference can be considered a problem of degree, which does not lead to a substantial change in the perception of the compound.

As mentioned above, there are some theoretical reasons why this is considered as 5-HT_1AAgonists and/or 5-HT₃Antagonist compounds are expected to be useful in the treatment of cognitive deficits and are supported by clinical evidence. Sumiyoshi reports a study in am.J.Psych., 158, 1722-one 1725, 2001 in which patients received typical antipsychotics such as haloperidol, sulpride and pimozide (all of which lack 5-HT)_1AActive), combined with placebo or tandospirone (a 5-HT)_1AAn agonist). Patients receiving tandospirone over antipsychotic showed improvement in their cognitive ability, while patients receiving placebo did not. Similarly, also as 5-HT_1AAtypical antipsychotics of agonists such as clozapine enhance cognition in schizophrenic patients, however none of the 5-HT_1ATypical antipsychotics that are active, such as haloperidol, do not enhance cognition in schizophrenic patients [ y.chung, Brain res, 1023, 54-63, 2004]. In healthy male subjectsIn a randomized double-blind crossover study, assessment of speech and spatial memory and sustained attention showed 5-HT₃The antagonist alosetron attenuates scopolamine-induced language and spatial memory deficits [ Preston, Recent Advances in the treatment of neurological disorders and cognitive function, 1994, (eds.). Racagni and Langer, Basel Karger, pp.89-93]。

As shown in example 5, the compounds of the present invention cause an increase in extracellular acetylcholine levels in the prefrontal cortex and ventral hippocampus of rats. These preclinical findings are expected to translate into clinical effects in the treatment of cognitive disorders, for example in Alzheimer's disease, in contrast to (cf.) the use of acetylcholinesterase inhibitors in the treatment of cognitive disorders. Furthermore, support for this view can also be found in example 6, where the data show that the compounds of the invention increase associative memory (associative memory) in rats. In general, the pharmacological profile of the compounds of the invention, combined with their effect on acetylcholine levels and memory in rats, strongly suggests that the compounds used in the invention are useful in the treatment of cognitive disorders or in the treatment of diseases in patients also suffering from cognitive disorders.

Cognitive disorders are among the standard features of depression, such as, for example, major depressive disorder. Cognitive disorders may continue to develop to some extent in depression, in the sense that an improvement in the depressed state will also lead to an improvement in cognitive disorders. However, there is also clear evidence that cognitive disorders are actually independent of depression. For example, studies have shown persistent cognitive impairment on the basis of depression recovery [ J.Nervous Mental Disease, 185, 748-754, 1997 ]. Furthermore, the different effects of antidepressants on depression and cognitive disorders further support the relatively independent claims that depression and cognitive disorders are relatively independent, although they often co-morbid. Although 5-hydroxytryptamine and norepinephrine drugs give comparable improvement in depression symptoms, several studies have shown that modulation of the noradrenergic system does not improve cognitive function as does 5-hydroxytryptamine modulation [ brain res. fill., 58, 345-350, 2002; hum Psychpharmacol, 8, 41-47, 1993 ].

Cognitive function is often impaired in schizophrenic patients and forms part of the so-called negative symptoms of schizophrenia. Cognitive function is also impaired in ADHD patients.

Cognitive deficits or disorders include decline in cognitive function or cognitive domains, such as working memory, attention and alertness, language learning and memory, visual learning and memory, reasoning, and problem solving, such as executive function, processing speed, and/or social cognition. In particular, cognitive deficits or disorders may manifest as a lack of attention, disorganized thinking (disorganized thinking), slow thinking, difficulty in understanding, difficulty in concentrating attention, reduced ability to solve problems, poor memory, difficulty in expressing thoughts, and/or difficulty in integrating thoughts, emotions, and behaviors, or difficulty in eliminating unrelated thoughts. The terms "cognitive deficit" and "cognitive disorder" refer to the same and are used interchangeably.

The data given in example 4 show that compound I is useful in the treatment of pain, and that it even has an analgesic effect; further studies in animal models of neuropathic pain demonstrate this observation. Accordingly, compound I is useful in the treatment of pain and affective or mood disorders, such as depression and anxiety associated with pain, and in particular chronic pain. Chronic pain includes indications (indications) such as phantom limb pain, neuropathic pain, diabetic neuropathy, post-herpetic neuralgia (PHN), Carpal Tunnel Syndrome (CTS), tarsal tunnel syndrome (tarsus tunnel syndrome), ulnar nerve entrapment, spinal cord compression, HIV neuropathy, complex regional pain syndrome (CPRS), trigeminal neuralgia (trigeminus neuralila)/trigeminus pain (trigeminus neuraligia)/trigeminus pain (tic doureuux), surgery (e.g., post-operative analgesia), diabetic vasculopathy, capillary resistance or diabetic symptoms associated with insulitis, pain associated with angina, pain associated with menstruation, pain associated with cancer, toothache, headache, migraine, tension headache, trigeminus neuralgia, temporomandibular joint syndrome, myofascial pain muscle damage, fibromyalgia syndrome, bone and joint pain (osteoarthritis), Rheumatoid arthritis, rheumatoid arthritis and oedema from wounds associated with burns, sprains or fractures, pain from osteoarthritis, osteoporosis, bone metastases or unknown causes, gout, fibrositis, myofascial pain, thoracic outlet syndrome, upper or lower back pain (where back pain is caused by systemic, local or primary spine disease (radiculopathy)), pelvic pain, cardiac chest pain, non-cardiac chest pain, pain associated with Spinal Cord Injury (SCI), central post-stroke pain, cancer neuropathy, AIDS pain, sickle cell pain, whiplash injury (whiplash) or geriatric pain.

Compound I has been tested in clinical trials using HAM-D (Hamilton rating Scale for Depression) as the clinical endpoint. The HAM-D scale may utilize a 24-item questionnaire to assess the severity of the patient's depression. Items 4, 5 and 6 of the scale relate to how the patient sleeps, i.e. whether it is easy to fall asleep (difficulty in falling asleep), whether the patient wakes up during the night (not deep asleep) and whether the patient wakes up early in the morning (early awake). The compounds were tested at 5 and 10mg per day versus placebo, with approximately 100 patients per group (arm). The data in figures 6-8 clearly show that compound I caused a large and dose-dependent improvement in sleep patterns, which is superior to the results given by placebo. Sleep disorders are well known to be a general adverse effect of most antidepressants. In particular, SSRIs and compounds that inhibit the norepinephrine transporter have been reported to cause problems with sleep initiation and maintenance, and often also with insomnia [ int. clin. psychpharm., 21(suppl 1), S25-S29, 2006 ]. Others have reported that this compound causes REM sleep inhibition, increased sleep latency, decreased sleep efficiency, increased nocturnal arousal and sleep fragmentation (fragmentation) [ hum. Thus, it is a surprising result that administration of compound I is not associated with adverse sleep effects, but in fact provides an improvement in sleep patterns. Thus, the compounds used in the present invention are useful in the treatment of sleep disorders such as difficulty falling asleep, frequent night wakefulness and early wakefulness.

The clinical trials described above also yielded patient-reported sexual adverse effects. The following table shows the number of patients reporting a particular type of sexually relevant adverse effect.

Reported adverse effects	Placebo	5mg	10mg
				Loss of sexual pleasure	0	0	0
Delaying ejaculation	0	0	0
				Erectile dysfunction	0	0	0
Decreased libido	0	1	1

Orgasm of orgasm	2	0	0
				Loss of libido	0	1	0
Reduced orgasm sensation	0	0	0

It is well known that treatment with antidepressants in general, and SSRIs in particular, may be associated with sexual dysfunction and this often leads to discontinuation of treatment. Up to 30-70% of patients using SSRIs report sexual dysfunction [ j.clin.psych., 66, 844-. The above results show that the sexual adverse effects of compound I are similar to placebo and therefore far better than normally expected for antidepressants, particularly SSRIs. The compounds for use in the present invention are useful in the treatment of sexual dysfunction, such as anorgasmia, delayed ejaculation, erectile dysfunction, decreased libido, orgasmic abnormalities, loss of libido or decreased orgasmic sensation.

The adverse effects of disruption of sleep and sexual activity are very unacceptable to patients and especially to patients who are used for prolonged periods, not to mention long-term treatment, which would cause treatment interruptions. The absence of these adverse effects in treatments involving administration of compound I makes compound I particularly useful in therapeutic interventions for extended periods of time, such as for example in the prevention of recurrence of depression.

The beneficial effects on sleep patterns caused by compound I make the use of compound I as described herein particularly attractive in the treatment of patients who already have a sleep problem or suffer from a sleep disorder or from a sexually relevant disorder.

The compounds used in the present invention may also be used as second-line therapy in patients who cannot use other drugs due to sleep or sex related adverse events, such as other antidepressants, e.g., 5-hydroxytryptamine reuptake inhibitors (SSRIs), selective Norepinephrine Reuptake Inhibitors (NRIs), norepinephrine/5-hydroxytryptamine reuptake inhibitors (SNRIs), or tricyclic antidepressants (TCAs). In such embodiments, the patient to be treated has used (or is still using) an additional drug therapy that is deactivated or reduced (or has to be deactivated or reduced) due to sleep or sex-related adverse events. Typically, patients suffer from mood disorders such as depression and anxiety, abuse (alcohol, narcotics, etc.) or chronic pain disorders.

The unique pharmacological profile of compound I in combination with the unexpectedly good safety profile makes compound I useful for the treatment of e.g. circadian rhythm disorders, sleep disorders breathing; hypopnea syndrome; abdominal pain; depression, especially major depression; dysthymic disorder; a circulatory psychosis; total depression (exaustive depression); atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia such as alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, and asperger syndrome; leukoencephalopathy (leucotrichiosis); small vascular disease; depression accompanied by abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression) and pain, especially gastrointestinal pain such as, for example, Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; compulsive and attention spectrum disorders in ADHD, asperger syndrome, and autism; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; eating disorders such as obesity, hyperphagia, anorexia, and bulimia nervosa; behavioral disorders (product disorders); behavioral disorders (behavioural disorders); behavioral disorders accompanied by dementia; flight fear; fear of the elevator; fear of small space; and amblyopia. The treatment of these diseases by administration of compound I is particularly useful and beneficial because of the desire for unwanted sleep-related side effects and because of the expected effects also on cognitive disorders associated with many of the above-mentioned diseases.

In this context "major depression" is a patient scoring greater than 30 on the MADRS scale, for example greater than 32 or greater than 35.

In one embodiment, the present invention relates to a method of treating a disease selected from the group consisting of circadian rhythm disorders; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced sensation of orgasm, comprising administering to a patient in need thereof a therapeutically effective amount of compound I.

In one embodiment, a patient receiving treatment has been diagnosed with a disease for which the patient is being treated.

In one embodiment, the patient being treated has previously been treated for the disease (or is still using) a drug therapy, such as other antidepressants, for example, a selective 5-hydroxytryptamine reuptake inhibitor (SSRI), a selective Noradrenaline Reuptake Inhibitor (NRI), a noradrenaline/5-hydroxytryptamine reuptake inhibitor (SNRI), or a tricyclic antidepressant (TCA), that is discontinued or reduced (or has to be discontinued or reduced) due to sleep or sex related adverse events. In this embodiment, the compounds used in the present invention are administered as a second line therapy.

As used herein, a "therapeutically effective amount" of a compound refers to an amount sufficient to cure, alleviate or partially arrest the clinical manifestations of a given disease and its complications in a therapeutic intervention involving administration of the compound. An amount sufficient to achieve this goal is defined as a "therapeutically effective amount". Sufficient amounts for each purpose will depend on the severity of the disease or injury as well as the weight and general state of the subject. It will be appreciated that appropriate dosages can be obtained using routine experimentation by constructing a matrix of values and testing the various points in the matrix, all within the routine skill of a trained physician.

The terms "treatment" and "treating" as used herein refer to the management and care of a patient for the purpose of combating a condition, such as a disease or disorder. The term is meant to encompass a broad spectrum of treatments for a given condition suffered by a patient, such as administration of the active compound to alleviate the symptoms or complications, delay the development of the disease, disorder or condition, alleviate or alleviate the symptoms and complications, and/or cure or eliminate the disease, disorder or condition and prevent the condition, wherein prevention is to be understood as management and care of the patient for the purpose of combating the disease, disorder or condition, which includes administration of the active compound to prevent the onset of the symptoms or complications. However, prophylactic (prophylactic) and therapeutic (curative) treatment are two separate aspects of the invention. The patient to be treated is preferably a mammal, in particular a human being.

Typically, treatment of the invention will involve daily administration of a compound of the invention. This may include once daily administration, twice daily administration, or even more frequent administration.

In one embodiment, the present invention relates to the use of compound I for the preparation of a medicament for the treatment of a disease selected from the group consisting of circadian rhythm disorders; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced orgasm perception. In one embodiment, the medicament is used in patients who have previously been (or are still being) treated with other drug therapies, such as other antidepressants, for example, selective 5-hydroxytryptamine reuptake inhibitors (SSRIs), selective Noradrenaline Reuptake Inhibitors (NRIs), noradrenaline/5-hydroxytryptamine reuptake inhibitors (SNRIs), or tricyclic antidepressants (TCAs), which are inactivated or reduced (or have to be inactivated or reduced) due to sleep or sex-related adverse events.

In one embodiment, the present invention relates to compound I for use in the treatment of a disease selected from the group consisting of circadian rhythm disorders; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced orgasm perception. In one embodiment, compound I is administered to a patient who has previously been administered (or is still being administered) other drug therapy, such as other antidepressants, such as, for example, a selective 5-hydroxytryptamine reuptake inhibitor (SSRI), a selective Noradrenaline Reuptake Inhibitor (NRI), a noradrenaline/5-hydroxytryptamine reuptake inhibitor (SNRI), or a tricyclic antidepressant (TCA), which is or has to be discontinued or reduced (or has to be discontinued or reduced) due to sleep or sex-related adverse events.

Compound I is conveniently presented in the form of a pharmaceutical composition, which may be prepared by methods conventional in the art. Mention is made in particular of the preparation of tablets, which can be prepared by mixing the active ingredient with the usual auxiliaries and/or diluents and subsequently compressing the mixture on a conventional tabletting machine. Examples of adjuvants or diluents include: anhydrous calcium hydrogen phosphate, PVP-VA copolymer, microcrystalline cellulose, sodium starch glycolate, corn starch, mannitol, potato starch, talc, magnesium stearate, gelatin, lactose, gums, and the like. Any other adjuvants or additives conventionally used for such purposes may be used, such as colorants, flavors, preservatives, and the like, provided they are compatible with the active ingredient.

Solutions for injection can be prepared by the following method: the active ingredient and possible additives are dissolved in a portion of the solvent used for injection, preferably sterile water, the solution is adjusted to the desired volume, the solution is sterilized and filled in suitable ampoules or vials. Any suitable additive commonly used in the art may be added, such as tonicity adjusting agents, preservatives, antioxidants, and the like.

The pharmaceutical compositions prepared according to the present invention may be administered by any suitable route, for example orally in the form of tablets, capsules, powders, syrups and the like, or parenterally in the form of solutions for injection. To prepare such compositions, methods well known in the art may be used, and any pharmaceutically acceptable carrier, diluent, excipient, or other additive commonly used in the art may be used.

Conveniently, compound I is administered in a unit dosage form comprising an amount of the compound of about 1 to 50 mg. Is believed to be according to 5-HT₃The concentration of the activity sets the upper limit depending on the case. The total daily dose is usually about 1-20 mg/ratioSuch as from about 1 to 10mg, from about 5-10mg, from about 10-20mg or from about 10-15mg of a compound of the invention. Particular mention may be made of a daily dose of 2.5, 5, 10, 15 or 20 mg.

Tablets comprising compound I may conveniently be prepared by wet granulation. Using this method, dry solids (active ingredients, fillers, binders, etc.) are blended, moistened with water or another wetting agent (e.g. ethanol), and the moistened solids are made into agglomerates or granules. Wetting of the pellet is continued until the desired uniform particle size is obtained, at which point the granulated product is dried. Typically, compound I, lactose monohydrate, corn starch, and copovidone (copovidone) are mixed with water in a high shear mixer. After the granules are formed, the granules may be sieved in a screen having a suitable mesh and dried. Next, the resulting dried granules are mixed with microcrystalline cellulose, croscarmellose sodium and magnesium stearate, and then compressed into tablets. Alternatively, wet granulation of the compounds of the present invention can be achieved using mannitol, corn starch and copovidone, which is mixed with microcrystalline cellulose, sodium starch glycolate and magnesium stearate, followed by compression into tablets. Alternatively, wet granulation of compound I can be achieved by using anhydrous dibasic calcium phosphate, corn starch and copovidone, mixing the granules with microcrystalline cellulose, sodium starch glycolate (type a), talc and magnesium stearate, followed by compression into tablets. The copovidone is PVP-VA copolymer.

In one embodiment, compound I is the hydrobromide salt, e.g. form beta, and a suitable tablet may have a composition which is w/w% expressed as a percentage

HBr salt 3-8%

35 to 45 percent of anhydrous calcium hydrophosphate

15-25% of corn starch

2 to 6 percent of copovidone

20-30% of microcrystalline cellulose

1-3% of sodium starch glycolate

2 to 6 percent of talcum powder

Magnesium stearate 0.5-2%

In particular, the tablet may be composed as follows

HBr salt about 5%

Anhydrous calcium hydrogen phosphate is about 39%

About 20% of corn starch

Copovidone is about 3%

Microcrystalline cellulose approximately 25%

Sodium starch glycolate approximately 3%

Talc powder is about 4%

Magnesium stearate approximately 1%

By selecting the correct amount of compound I and the appropriate size of the tablet, tablets with different amounts of active compound, e.g. corresponding to e.g. 2.5, 5, 10, 20, 25, 30, 40, 50, 60 or 80mg of the free base, can be obtained.

Compound I can be administered alone or in combination with other therapeutically active compounds, wherein both compounds can be administered simultaneously or sequentially. Examples of therapeutically active compounds which are advantageous in combination with compound I include sedatives or hypnotics, such as diazepam (benzodiazepines); anticonvulsants such as lamotrigine, valproic acid, topiramate, gabapentin, carbamazepine; mood stabilizers such as lithium; dopaminergic agents, such as dopamine agonists and levodopa; drugs that treat ADHD, such as atomoxetine; psychostimulants such as modafinil, ketamine, methylphenidate and amphetamine; other antidepressants, such as mirtazapine, mianserin and bupropion; hormones, such as T3, estrogen, DHEA and testosterone; atypical antipsychotics, such as olanzapine and aripiprazole; typical antipsychotics, such as haloperidol; drugs for the treatment of alzheimer's disease, such as cholinesterase inhibitors and amantadine, folate; s-adenosylmethionine; immunomodulators, such as interferons; opiates, such as buprenorphine; angiotensin II receptor 1 antagonists (ATI antagonists); an ACE inhibitor; a statin; and alpha adrenergic antagonists, such as prazosin.

The free base of compound I may be prepared as disclosed in WO 2003/029232 or WO 2007/144005. The salts used in the present invention can be prepared by the following method: the free base is dissolved in a suitable solvent, the corresponding acid is added, and precipitation follows. Precipitation may be achieved by addition of a second solvent and/or evaporation and/or cooling. Alternatively, the free base used in the present invention may be synthesized in a palladium catalyzed reaction as described in the examples.

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference in their entirety to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein (to the maximum extent permitted by law), whether or not such incorporated reference is provided anywhere else herein individually.

The use of the terms "a" and "an" and "the" and similar referents in the context of describing the invention is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. For example, unless otherwise indicated, the word "the compound" is understood to refer to various compounds or specifically described aspects of the invention.

Unless otherwise indicated, all precise values provided herein are approximations (e.g., all precise sample or measured values provided with respect to a particular factor may be considered to also provide a corresponding approximate measurement, with the value modified by "about" where appropriate).

The use of terms such as "comprising," "having," "including," or "containing" with respect to individual elements herein, to describe any aspect or aspect of the invention, means that the description of "consisting of …," "consisting essentially of …," or "consisting essentially of" one or more particular elements of a similar aspect or aspect of the invention provides support unless otherwise stated or clearly contradicted by context (e.g., a composition described herein as including a particular element should be understood as also being a composition that can be described as consisting of those elements, unless otherwise stated or clearly contradicted by context).

Examples

Analytical method

¹ H NMR Spectrum: was recorded at 500.13MHz in a Bruker Avance DRX500 apparatus. Dimethyl sulfoxide (99.8% D) was used as solvent and Tetramethylsilane (TMS) was used as internal reference standard.

Melting Point: is measured using Differential Scanning Calorimetry (DSC). The apparatus used was a TA-Instruments DSC-Q1000 calibrated at 5 deg./min to give a melting point as starting value. Approximately 2mg of the sample was heated at 5 deg./min in a non-tightly sealed pan under a stream of nitrogen.

Thermogravimetric analysis (TGA):thermogravimetric analysis for determination of solvent/water content in dry matter was performed using TA-instruments TGA-Q500. 1-10mg of the sample was heated at 10 deg./min in an open pan under a stream of nitrogen.

X-ray powder diffraction pattern: on a PANALYTICAL X' Pert PRO X-ray diffractometer, CuK is used_α1Radiometric X-ray powder diffractograms. The samples were measured in reflectance mode using an X' celerator detector over the 2 theta range 5-40 °. The reflection values are given as ± 0.1(° 2 θ).

Example 1 in vitro receptor pharmacology

Rat 5-hydroxytryptamine vehicle: IC (integrated circuit)₅₀5.3nM (blocking absorption of 5-HT)

Human 5-hydroxytryptamine vehicle: IC (integrated circuit)₅₀5.4nM (blocking absorption of 5-HT)

Human 5-HT_IAReceptor: k_i15nM, agonism (96% efficacy or intrinsic activity)

Rat 5-HT₃Receptor: IC (integrated circuit)₅₀0.2nM (antagonism in functional assays)

Human 5-HT₃A receptor: IC (integrated circuit)₅₀About 20nM (antagonism in the functional assay). At higher concentrations, the compounds show agonist activity, ED₅₀At 2.1. mu.M. The compounds of the invention also exhibit binding to human 5HT in an in vitro binding assay₃The receptor has high affinity (Ki 4.5 nM).

EXAMPLE 2a preparation of the free base of Compound I

10 g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] are treated with a stirred mixture of 100ml of 3M NaOH and 100ml of ethyl acetate]Piperazine hydrobromide for 10 min. The organic phase is separated, washed with 100ml of 15% wt NaCl (aq) and MgSO₄Drying, filtration and concentration in vacuo gave 7.7 g (98%) of compound I as a clear colorless oil as the base.

NMR is in accordance with the structure.

EXAMPLE 2b preparation of crystalline base of Compound I

3.0 g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] piperazine as a colourless oil are treated with 70ml of acetonitrile and heated to reflux. The almost clear solution was filtered, the clear filtrate was naturally cooled, and by this operation, precipitation started shortly after filtration. The mixture was stirred at room temperature (22 ℃ C.) for 2 hours, the product isolated by filtration and dried in vacuo (40 ℃ C.) overnight. The crystalline base was isolated as a white solid, 2.7 g (90%). NMR is in accordance with the structure. Elemental analysis: 72.40% C, 9.28% N, 7.58% H (theoretical values: 72.26% C, 9.36% N, 7.42% H)

Example 2c characterization of the crystalline base of Compound I

The base as prepared in example 2b was crystalline (XRPD) -see figure 1. Its melting point was-117 ℃. It is non-hygroscopic and has an aqueous solubility of 0.1 mg/ml.

EXAMPLE 2d preparation of the alpha hydrobromide salt of Compound I

2.0 g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] piperazine were dissolved in 30ml of hot ethyl acetate and 0.73ml of 48% -wt HBr (aq) was added. This addition resulted in the formation of a concentrated (thick) slurry and an additional 10ml of ethyl acetate was added for stirring. The slurry was stirred at room temperature for 1 hour. Filtration and drying in vacuo (20 ℃) overnight gave 2.0 g of the product as a white solid (80%). NMR is in accordance with the structure. Elemental analysis: 57.05% C, 7.18% N, 6.16% H (theoretical value for 1: 1 salt: 56.99% C, 7.39% N, 6.11% H)

Example 2e characterization of the alpha hydrobromide form of Compound I

The α -form hydrobromide as prepared in example 2d was crystalline (XRPD) — see figure 2. It has a melting point of-226 ℃. When exposed to an environment of high relative humidity, the material absorbs about 0.3% water and has a water solubility of 2 mg/ml.

EXAMPLE 2f preparation of beta-form of Compound I hydrobromide

49.5 g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] piperazine colourless oil are dissolved in 500ml of ethyl acetate and 18.5ml of 48% wt HBr (aq) are added. This addition operation caused the formation of a concentrated slurry which was stirred at room temperature overnight. Filtration and drying in vacuo (50 ℃) overnight gave 29.6 g of the product as a white solid (47%).

NMR is in accordance with the structure. Elemental analysis: 56.86% C, 7.35% N, 6.24% H (theoretical value for 1: 1 salt: 56.99% C, 7.39% N, 6.11% H).

Example 2g characterization of beta hydrobromide of Compound I

The beta form of the hydrobromide as prepared in example 2f is crystalline (XRPD), see figure 3. It has a melting point of-231 ℃. When exposed to high relative humidity, the material absorbs about 0.6% water and has a water solubility of 1.2 mg/ml.

EXAMPLE 2h preparation of the gamma hydrobromide salt of Compound I

1g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] piperazine hydrobromide, prepared as in example 2d, was added to 20ml of water and heated to 85 ℃. The solution was almost clear. 1 drop of HBr was added to clarify it. HBr was added until a cloud point was observed. The solution was cooled to room temperature and dried. NMR is in accordance with the structure. Elemental analysis: 56.63% C, 7.18% N, 6.21% H (theoretical 1: 1 salt: 56.99% C, 7.39% N, 6.11% H).

Example 2I characterization of Compound I's hydrobromide form gamma

The hydrobromide as prepared in example 2h was crystalline (XRPD) -see figure 4. DSC curves show that some thermal events occurred at about 100 ℃; the crystal form may be changed. It then melts at about 220 ℃. It absorbs about 4.5% water when exposed to high relative humidity, and about 2% water at 30% RH and room temperature.

EXAMPLE 2j preparation of hydrobromide hydrate of Compound I

1.4 g of 1- [2- (2, 4-dimethylphenylsulfanyl) -phenyl ] piperazine oil were added to 20ml of water and heated to 60 ℃. The pH was adjusted to 1 using 48% HBr. The solution was cooled to room temperature and dried. NMR is in accordance with the structure. Elemental analysis: 55.21% C, 7.16% N, 6.34% H (theoretical value for 1: 1 salt hemihydrate: 55.68% C, 7.21% N, 6.23% H).

Example 2k characterization of the hydrobromide hemihydrate of Compound I

The hydrate as prepared in example 2j was crystalline (XRPD) -see figure 5. The water content depends mainly on the relative humidity. The water content was about 3.7% at room temperature and 95% RH. Dehydration was carried out by heating to about 100 ℃.

EXAMPLE 3 preparation of Compound I

815g of NaOBu^t(8.48mol), 844g of piperazine (9.8mol), 6.6g of Pd (dba)₂(11.48mmol) and 13.6g of rac-BINAP (21.84mmol) were stirred with 4L of toluene for 50 minutes. 840g of 2-bromo-iodobenzene (2.97mol) are subsequently added together with 1.5L of toluene and stirring is continued for 30 minutes. Finally, 390.8g of 2, 4-dimethylthiophenol (2.83mol) were added together with 1.5L of toluene. The suspension was heated to reflux and reflux continued for 5 hours. The reaction mixture was cooled overnight. 2L of water were added and stirred for 1 hour, and then the mixture was filtered through a filter aid. The filtrate was then washed with 3X 1L of brine. The combined aqueous phases were then extracted with 600ml of toluene. The combined toluene phases were heated to 70 ℃ and 329.2ml of 48-wt.% HBr (aq) and 164.6ml water were added. The mixture was cooled at room temperature overnight. The final product (1- [2- (2, 4-dimethyl-phenylsulfanyl) -phenyl) -was collected by filtration]Piperazine hydrobromide) and drying under vacuum (60 ℃ C.) gave 895g (84% yield).

Example 4 Effect on mouse intradermal formalin test induced pain

In this model, the left hind paw of the mouse received an injection of formalin (4.5%, 20 μ l). The stimulus caused by formalin injection elicits a characteristic two-phase behavioral response, as quantified by the amount of time it takes to lick the injured paw. The first phase (-0-10 minutes) represents direct chemical stimulation and nociception, while the second phase (-20-30 minutes) is considered to represent pain of neuropathic origin. These two phases are separated by a quiescent period in which behavior returns to normal. The efficacy of the test compounds in reducing pain stimuli was evaluated by calculating the amount of time it took to lick the injured paw in two stages.

Compound I showed a significant reduction in the second phase pain score (fig. 9a), indicating the efficacy of the compound against pain of neuropathic origin. Furthermore, the compound of the invention showed a significant reduction in the first stage score (fig. 9b), indicating that the compound had a higher analgesic effect at the highest dose. Taken together, these results indicate that the compounds of the invention are likely to have efficacy in treating pain conditions.

Example 5 Effect on extracellular acetylcholine levels in the brain of free-moving rats

1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine, HBr salt, is administered to the animal.

Animal(s) production

Male Sprague-Dawley rats with an initial weight of 275-300g were used. The animals were kept under 12 hours light/dark cycle under controlled conditions of normal room temperature (21 + -2 deg.C) and humidity (55 + -5%), with food and tap water available ad libitum.

Surgical and microdialysis assays

Rats were anesthetized with fentanyl (hypnorm)/parasomnia (dormicum) (2ml/kg) and an intracerebral catheter (CMA/12) was implanted into the brain in a stereotactic manner, aiming to position the tip of the dialysis probe in the ventral hippocampus (coordinates: 5,6mm posterior to bregma, lateral-5, 0mm, ventral dura mater 7,0mm) or in the prefrontal cortex (coordinates: 3,2mm anterior to bregma; lateral, 0,8 mm; ventral dura mater 4,0 mm). The catheter was secured using anchor screws and acrylic cement. The temperature of the animals was monitored with a rectal probe and maintained at 37 ℃. The rats subjected to the surgery were recovered for 2 days and individually housed in cages. On the day of microdialysis experiments, a probe (CMA/12, diameter 0,5mm, length 3mm) was inserted into the catheter.

The probe and the microinjection pump were connected via a two-channel swivel. Shortly before insertion of the probe into the brain, use was started with a filtered Ringer solution (145mM NaCl, 3mM KCl, 1mM MgCl)₂1,2mM CaCl containing 0.5. mu.M neostigmine₂) Microdialysis probes were perfused and continued at a constant rate of 1. mu.l/min for the entire duration of the experiment. After stabilizing for 180 minutes, the test was started. The dialysate was collected every 20 minutes. After the experiment was completed, the animals were sacrificed and their brains were removed, frozen and sectioned for probe fixation (displacement verification).

The compounds were dissolved in 10% HP β CD and injected subcutaneously (2.5-10 mg/kg). The dose is expressed in mg salt/kg body weight. The compound was administered in an amount of 2.5 ml/kg.

Analysis of acetylcholine in dialysate

The concentration of acetylcholine (ACh) in the dialysate was analyzed by HPLC with electrochemical detection using a mobile phase consisting of 100mM disodium hydrogen phosphate, 2.0mM octanesulfonic acid, 0.5mM tetramethylammonium chloride and 0.005% MB (ESA), pH 8.0. A pre-separation column enzyme reactor (ESA) containing immobilized choline oxidase had removed choline from the injected sample (10 μ Ι) before ACH was separated on the analytical column (ESA ACH-250); flow rate 0.35ml/min, temperature: 35 ℃ is carried out. After the analytical column, the sample is passed through a post-column solid phase reactor (ESA) containing immobilized acetylcholinesterase and choline oxidase. The latter reactor converts ACh to choline, which, in turn, converts choline to betaine and H₂O₂. The latter was detected electrochemically by using a platinum electrode (analytical cell: ESA, model 5040).

Data representation

In a single injection trial, the average of 3 consecutive ACh samples immediately preceding compound administration was taken as the basal level for each trial and the data was converted to a percentage of the basal level (normalizing the pre-injection mean baseline value to 100%).

Results

The compound significantly increased the level of extracellular ACh in the prefrontal cortex and ventral hippocampus in rats-see figures 10a and 10 b.

Example 6 Association conditioned fear in rats

In this test, the compound administered is the HBr salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine.

We investigated the effect of the compound on acquisition (acquisition), potentiation and regression of rat associative conditioned fear. In conditioned fear, example animals are made to learn to combine a neutral environment (context), training room, CS) with an aversive experience (shock to foot, US). During re-exposure to the training chamber, the animals exhibited stiff behaviour, which would serve as a direct measure of fear-related memory [ Pavlov j. biol. sci., 15, 177-182, 1980 ]. The neuroanatomy of associative conditioned fear has been thoroughly studied, and several studies have demonstrated that the Hippocampus and amygdala are essential for developing this memory [ Hippocampus, 11, 8-17, 2001; j Neurosci, 19, 1106-1114, 1999; behav. neurosci, 106, 274-charge 285, 1992.

Animal and medicine

Adult male Sprague-Dawley rats (weight 250-300g at training) from Charles River Laboratories were used, housed two per cage, under a 12h light/dark cycle. Food and water are available ad libitum. The rats were used 1 week after arrival. The compounds were dissolved in 10% HP β CD and injected subcutaneously. The drug was administered in an amount of 2.5 ml/kg.

Device for measuring the position of a moving object

Training and testing was performed in a sound-proof booth (30X 20X 40cm) located in an insulated room and connected to a ventilation system. Illumination was provided by white light (60 watts). The floor of the sound isolation booth is comprised of a metal mesh attached to an electric shock generator. Prior to training and testing, the chamber was rinsed with a 70% ethanol solution. The cameras are allowed to conduct behavioral observations and record training sessions for offline analysis.

Test of acquisition and maintenance

During the acquisition period, the animals were allowed to freely explore the new environment for an adaptation period of 1 minute, which was terminated with one non-evasive shock (unconditional stimulation, US) to the foot through a charged grid ground. The duration of the foot shock is 2s, and the intensity is 0.75 mA. After US, rats were kept in the conditioned chamber for an additional 60 seconds. At the first 58 seconds, catalepsy behavior was scored (obtained before shock; experimenters were blinded to each group) to determine baseline-catalepsy responses to background. At the end of the acquisition, the animals are gently removed and placed in their rearing cages. After 24h, the same animals were reintroduced into the training background (fear conditioning chamber) and a 2 minute hold test was performed. During this period, no foot shock is applied. The catalepsy was scored by the experimenter blind to each group throughout the test period and expressed as a percentage of the total test period.

Results and discussion

The effect of the compound on associative conditioned fear in rats was studied by (i) acquisition (drug administered prior to acquisition, fig. 11), (ii) memory recovery (drug administered prior to testing, fig. 12) and (iii) boost (drug administered immediately after acquisition, fig. 13). In the first set of experiments, the compound was administered 1h prior to the acquisition period (1, 5 and 10 mg/kg). Fig. 11 depicts the acquisition of catalepsy during training (58 seconds prior to foot shock) and retention tests performed 24 hours thereafter. The following findings were observed:

any dose of the compound tested did not affect baseline catalepsy prior to foot shock.

-5 mg/kg of the compound tended to increase the time spent rigor-ing during the holding test 24h after acquisition (39.24 ± 13.76%, n ═ 6, as opposed to 24.30 ± 4.40%, n ═ 16 in vehicle treated animals).

-10mg/kg of the compound significantly increased the time spent rigor-ing during the retention test 24h after acquisition (52.15 ± 5.68%, n ═ 10, as opposed to 24.30 ± 4.40%, n ═ 16, p < 0.01 in vehicle treated animals).

The conditioned fear model as described in fig. 11 is a standard method described in the literature for studying learning and memory. To further elucidate the short term (acute) effect of this drug on memory recovery, the compound (5, 10 and 20mg/kg) was administered 1h prior to the retention test. During memory testing, the compound at 5mg/kg was observed to inhibit the performance of catalepsy (12.86 ± 3.57%, n ═ 9, as opposed to 33.61 ± 4.29%, n ═ 13, p < 0.05 in vehicle-treated animals) (fig. 13).

As mentioned above, the compound itself did not affect baseline catalepsy before US began (fig. 11), and therefore, it seems the most reasonable hypothesis that those effects observed in fig. 12 are due to anxiolytic effects. Conditioned memory was assessed via catalepsy, a response that is reduced by compounds with potential anxiolytic effects. This experiment demonstrates that short term (administration) administration of the compound prior to memory recovery (recall) has anxiolytic effects, and therefore, it is unlikely that the increase in rigidity shown in figure 11 is due to anxiolytic (anxiogenic) effects of the compound.

To strengthen the compound not as anxiolytic but with cognitive (pro-cognitive) potential (this view), 5, 10 and 20mg/kg of the compound were administered after the acquisition period, respectively. Thus, in this set of experiments, the compound was not present (onboard) during the acquisition and throughout the retention test. Here, it was observed that 5mg/kg of the compound significantly increased the time taken to remain stiff during the test 24h after the acquisition period (45.58 ± 4.50%, n ═ 8, as opposed to 25.26 ± 3.57%, n ═ 19, p < 0.05 in vehicle-treated animals). The percentage of time spent rigor during association re-exposure has been described as a measure of fear-associated memory [ Pavlov j. biol. sci, 15, 177-182, 1980] which is enhanced in compound-treated rats when compared to vehicle-treated animals (figures 11 and 12). Taken together, the data show that the compounds enhance associative memory.

Claims (30)

1. A method of treating a disease selected from circadian rhythm disorders; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced sensation of orgasm, comprising administering to a patient in need thereof a therapeutically effective amount of compound I, which is 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof.

2. The method according to claim 1, wherein the patient is administered a hydrobromide salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine.

3. The method according to claim 2, wherein the salt is crystalline.

4. The method according to claim 3, wherein said salt is characterized by having major XRDP peaks at 6.89, 9.73, 13.78 and 14.62(° 2 θ), all ± 0.1(° 2 θ).

5. The method according to claim 4, wherein said salt is characterized by an XRDP as depicted in figure 3.

6. The method according to any one of claims 1-5, wherein compound I is administered to the patient in a unit dose of about 1-50 mg.

7. The method according to claim 6, wherein the patient is orally administered between about 1 and 20mg daily of the hydrobromide salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine.

8. The method according to any one of claims 1-7, wherein said patient is administered a therapeutically effective amount of Compound I, with the proviso that Compound I is not the free base of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine in amorphous form.

9. The method according to any one of claims 1-8, wherein the patient has previously received (or is still receiving) treatment for the disease with a drug therapy that is discontinued or reduced (or has to be discontinued or reduced) due to sleep or a sex-related adverse event.

10. Use of compound I in the manufacture of a medicament for the treatment of a disease selected from circadian disorders, wherein compound I is 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced orgasm perception.

11. Use according to claim 10, wherein compound I is the hydrobromide salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine.

12. Use according to claim 11, wherein the salt is crystalline.

13. Use according to claim 12, wherein the salt is characterised by having major XRDP peaks at 6.89, 9.73, 13.78 and 14.62(° 2 Θ), all ± 0.1(° 2 Θ).

14. The method according to claim 13, wherein the salt is characterized by an XRDP as depicted in figure 3.

15. The use according to any one of claims 10 to 14, wherein the medicament is a unit dose of about 1 to 50mg for oral administration of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof.

16. The use according to claim 15, wherein the medicament comprises between about 1 and 20mg of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine hydrobromide.

17. Use according to any one of claims 10 to 16, with the proviso that compound I is not the free base of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine in amorphous form.

18. The use according to any of claims 10-17, wherein the medicament is for a patient who has previously received (or is still receiving) treatment for the disease with a medication that is deactivated or reduced (or has to be deactivated or reduced) due to sleep or sex-related adverse events.

19. Compound I which is 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof for use in the treatment of a disease selected from circadian disorders; difficulty in falling asleep; waking up at night; early waking; sleep disordered breathing; hypopnea syndrome; major depression; dysthymic disorder; a circulatory psychosis; total depression; atypical depression; mood disorders accompanied by general medical disorders; substance-induced mood disorders; recurrent depression; single episode depression; depression in children; depression after stroke; peri-, pre-or post-menopausal dysphoria disorder; seasonal Affective Disorder (SAD); aggression and agitation in dementia or alzheimer's disease; compulsive and attention spectrum disorders in ADHD, autism, or asperger syndrome; cerebral leukopenia; small vascular disease; depression with abuse, irritability, hostility, sleep disorders, fatigue, huntington's chorea, multiple sclerosis, anxiety (anxious depression), pain, gastrointestinal pain or Irritable Bowel Syndrome (IBS); general anxiety disorder with pain; impulse control of disease; intermittent explosive disorder; nodules of pilferage; releasing pathogenic fire; pathological gambling; trichotillomania; negative symptoms of schizophrenia; mild cognitive impairment; vascular dementia; cognitive disorders accompanied by down's syndrome, tph gene mutations, ADHD, epilepsy, traumatic brain injury, or asperger's syndrome; aggression and agitation in dementia and alzheimer's disease; chronic fatigue syndrome; a stress-related disorder; acute stress; stress; exhaustion; insulin resistance accompanied by HPA axis hyperactivity; obesity; overeating; anorexia; bulimia nervosa; behavioral disorders; a behavioral disorder; behavioral disorders accompanied by dementia; age-related behavioral disorders; flight fear; fear of the elevator; fear of small space; amblyopia; loss of sexual pleasure; delaying ejaculation; erectile dysfunction; decreased libido; orgasm disorder; loss of libido; or reduced orgasm perception.

20. The compound according to claim 19, which is the hydrobromide salt of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine.

21. The compound according to claim 20, wherein the salt is crystalline.

22. The compound according to claim 21, wherein said salt is characterized by having major XRDP peaks at 6.89, 9.73, 13.78 and 14.62(° 2 Θ), all ± 0.1(° 2 Θ).

23. The compound according to claim 22, wherein said salt is characterized by an XRDP as depicted in figure 3.

24. The compound according to any one of claims 19-23, which is a unit dose of about 1-50mg for oral administration of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and pharmaceutically acceptable salts thereof.

25. The compound according to claim 24, wherein said unit dose comprises between about 1 and 20mg of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine hydrobromide.

26. A compound according to any one of claims 19 to 25, with the proviso that the compound is not the free base of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine in amorphous form.

27. A compound according to any one of claims 19-26 for use in the treatment of a patient who has previously received (or is still receiving) treatment for the disease with a drug therapy that has been discontinued or reduced (or has to be discontinued or reduced) due to sleep or a sexually related adverse event.

28. A method for treating a disease selected from depression, anxiety, abuse or chronic pain, comprising administering to a patient in need thereof a therapeutically effective amount of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and a pharmaceutically acceptable salt thereof, wherein the patient has previously received (or is still receiving) treatment for the disease with a drug therapy that has been discontinued or reduced (or has to be discontinued or reduced) due to a sleep or sex-related adverse event.

Use of 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and a pharmaceutically acceptable salt thereof in the manufacture of a medicament for the treatment of a disease selected from depression, anxiety, abuse or chronic pain, wherein the medicament is for use in a patient who has previously received (or is still receiving) treatment for the disease with a medication that has been discontinued or reduced (or has to be discontinued or reduced) due to sleep or a sexually related adverse event.

30. 1- [2- (2, 4-dimethylphenylsulfanyl) phenyl ] piperazine and a pharmaceutically acceptable salt thereof for use in the treatment of a disease selected from depression, anxiety, abuse, or chronic pain in a patient who has previously received (or is still receiving) treatment for the disease with a drug therapy that has been discontinued or reduced (or has to be discontinued or reduced) due to sleep or a sexually related adverse event.