The present invention is directed to compounds of general formula (I) as described and defined herein, methods of preparing said compounds, intermediate compounds useful for preparing said compounds, pharmaceutical compositions comprising said compounds, and the use of said compounds for manufacturing pharmaceutical compositions for the treatment or prophylaxis of diseases. The compounds of general formula (I), as described and defined herein, are found to inhibit Transient Receptor Potential Ankyrin 1 (TRPA1) receptor. In particular, the invention is directed to the use of such compounds for manufacturing a pharmaceutical composition for the treatment or prophylaxis of a disease, in particular in mammals, such as but not limited to diseases associated with pain and inflammation, or for the treatment or prophylaxis of pain-related/associated diseases, conditions and disorders and pain syndromes, gynecological diseases, urinary tract disorders and diseases, cancer and cancer-related pain, neurological disorders, respiratory disorders, gastrointestinal disorders, metabolic disorders, neurodegenerative disorders, skin disorders, cardiovascular disorders and inflammatory diseases.

BACKGROUND

Transient receptor potential (TRP) is a non-selective cation channel that can be found on cytomembranes and appears to have high permeability to calcium. Known TRP are for example Transient Receptor Potential Vanilloid 4 (TRPV4) and Transient Receptor Potential Ankyrin 1 (TRPA1) involved in pain and inflammatory mechanisms. WO2018/055527A1 and WO2018/055524A1 are reporting 2-sulfonamide-pyrrolidine analogs identified as Transient Receptor Potential Vanilloid 4 (TRPV4) antagonists useful for treating diseases and conditions including but not limited to pain, inflammation and endometriosis. WO2018/029288A1 is reporting 1-sulfonyl-2-carboxamide-pyridyl analogs identified as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonists useful for treating diseases and conditions including but not limited to pain, inflammation and endometriosis. W02018/180460A1 is reporting norbornane analogs identified as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist and WO2019/152465A1 is reporting 3,7-dihydropurine-2,6-dione analogs identified as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist useful for treating diseases and conditions including but not limited to pain and inflammation. JP2018/127440 is reporting isopropylcyclohexane analogs identified as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist or/and as Transient Receptor Potential Vanilloid 4 (TRPV4) antagonists useful for treating diseases and conditions including but not limited to pain and inflammation. W02 018/0230149A1 is reporting 3,7-dihydropurine-2,6-dione analogs, different from WO20 19/152465A1 , identified as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist useful for treating diseases and conditions including but not limited to pain and inflammation. WO2011/043954A1 is reporting decaline-4a-ol analogs including tetrahydropyranol analogs as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist useful for treating diseases and conditions including but not limited to pain and inflammation. WO2019/182925 is reporting oxadiazole analogs as Transient Receptor Potential Ankyrin 1 (TRPA1) antagonist useful for treating diseases and conditions including but not limited to pain and inflammation.

The present invention relates to chemical compounds that inhibit TRPA1 receptor. Transient Receptor Potential Ankyrin 1 (TRPA1) is one of the 28 members of the transient receptor potential (TRP) channel family and the sole member of the TRPA subfamily in mammals, TRPA1 is a voltage-dependent, ligand-gated and permeable to both monovalent and divalent cations. Its activation is therefore capable of depolarizing the membrane and initiating Ca ²⁺ signaling in the cells it is expressed [Jaquemar 1999, J Biol Chem 247(11):7325-33; Chen 2015, Naunyn Schmiedebergs Arch Pharmacol 388(4)451-63; Fernandes 2012, Br J Pharmacol 166(2);510-21; Viana 2016, J Physiol 594(15):4151-69; Skerrat 2017, Prog Med Chem 56:81-115],

TRPA1 is activated and modulated in multiple ways, directly or indirectly, by endogenous and exogenous reactive and non-reactive ligands. TRPA1 channels represent therefore an integrator of pro-nociceptive and pro-inflammatory signals. Endogenous ligands are e.g. oxidized lipids such as 4-hydroxy-2-nonenal, nitrated lipids, prostaglandins metabolites, reactive molecules such as H202, reactive metabolite such as methylglyoxal, endogenous gasotransmitters such as NO. Furthermore, TRPA1 can be modulated and activated by intracellular calcium and modulated by other receptors such as TRPV1, TSLP, PAR2 or B1R [Chen 2015, Naunyn Schmiedebergs Arch Pharmacol 388(4)451-63; Viana 2016, J Physiol 594(15):4151-69; Skerrat 2017, Prog Med Chem 56:81-115],

TRPA1 is broadly expressed but principally within the nervous system. As an example, TRPA1 was found to be highly expressed within small- and medium-sized peptidergic primary afferent somatosensory neurons present in sensory ganglia-containing nociceptors such as the dorsal root ganglia (DRGs) [Kim 2010, J Comp Neurol 518(5):687-98], In addition TRPA1 has been also found to be expressed in central neurons such as cortical neurons and in glial cells such as astrocytes and oligodendrocytes [Shigetomi 2013, J Neurosci 33(24): 10143-53; Saghy 2016, Glia 64(12):2166-2180; Kheradpezhouh 2017, Open Biol 7(4)]. In addition to its nervous system expression, TRPA1 has been described to be expressed in various tissues and cells such as vascular endothelium and all barrier tissues such as skin (e.g. keratinocytes, epithelial melanocytes), lung cells (fibroblast), gut, joint cells (e.g., synoviocytes, chondrocytes) and cancer cells [Jaquemar 1999, J Biol Chem 247(11):7325-33; Viana 2016, J Physiol 594(15):4151-69; Nummenmaa 2016, Arthritis Res Ther 18(1):185; Takahashi 2018, Cancer Cell 33(6):985-1003].

Based on its broad expression and its key role as a sensor of cellular stress, inflammation and tissue/cell damage, TRPA1 receptors are relevant therapeutic targets for different indications. The prominent role of TRPA1 receptors in acute nociception and chronic painful states has been described in various animal models, including mouse and rats models for acute, chronic and inflammatory pain [Chen 2015, Naunyn Schmiedebergs Arch Pharmacol 388(4)451-63; Viana 2016, J Physiol 594(15):4151-69; Skerrat 2017, Prog Med Chem 56:81-115], While it has been postulated thatTRPAI receptors may play a role in the transition from acute to chronic pain, it is also well documented that TRPA1 receptors are involved in acute nociception, inflammatory pain, neuropathic pain and other neurological conditions such as migraine [Chen 2015, Naunyn Schmiedebergs Arch Pharmacol 388(4)451-63; Viana 2016, J Physiol 594(15):4151 -69; Skerrat 2017, Prog Med Chem 56:81-115], A gain of function mutation in the human Trpal gene, located on chromosome 8q13, was described to be responsible of a disease, known as familial episodic pain syndrome-1. This disease is characterized by pain episodes triggered by fasting, cold and physical stress [Kremeyer2010, Neuron 66(5):671-80; Fernandes 2012, Br J Pharmacol 166(2):510-21], In addition to painful diseases, TRPA1 receptors have been described to be involved in disorders related or at least partially driven by neurogenic events such as skin disease, lung diseases, gastrointestinal tract disorders or urogenital disorders [Fernandes 2012, Br J Pharmacol 166(2):510-21 ; Chen 2015, Naunyn Schmiedebergs Arch Pharmacol 388(4)451-63; Viana 2016, J Physiol 594(15):4151-69; Skerrat 2017, Prog Med Chem 56:81-115]. Indeed, in addition to reducing spontaneous or evoked activation of the pain pathways (e.g., peripheral and central sensory neurons), TRPA1 antagonists also have the potential to decrease the peripheral release of pro-inflammatory neuropeptides such as CGRP or SP [Choi 2018, Semin Immunopathol 40(3):249-259]. It has been recently described that TRPA1 receptor are overexpressed in cancer cells and mediates a non-canonical ROS defense program. Cancer cell survival is dependent on oxidative-stress defenses against reactive oxygen species. ROS are accumulating during the development of the tumor and TRPA1 receptors have been described to promote ROS tolerance. TRPA1 antagonist may be therefore valuable compounds as cancer therapies [Takahashi 2018, Cancer Cell 33(6):985-1003].

Not so much is known about TRPA1 in gynecological conditions and only published information is referring to descriptive TRPA1 expression in rat and human tissues. Indeed, an estrogen-dependent up-regulation of TRPA1 has been described in the rat endometrium, TRPA1 mRNA was found to be significantly higher in the peritoneum from women with endometriosis and TRPA1 immunopositive cells were found in rectosigmoid deep infiltrating endometriosis lesions [Greaves 2014, J Clin Endocrinol Metab 99(9):E1738-43; Pohoczky 2016, J Mol Endocrinol 56(2): 135-49; Bohonyi 2017, Mol Pain 13:1744806917705564. While the expression of TRPA1 channels was described in endometrium and endometriosis patients, the use of TRPA1 antagonists for the prevention and/or the treatment of Transient Receptor Potential Ankyrin 1 (TRPA1) for use in the treatment and/or prevention of dysmenorrhea, dyspareunia, dysuria, dyschezia, endometriosis, endometriosis-associated pain or endometriosis-associated symptoms were until today never mentioned.

Therefore, inhibitors of TRPA1 of the current invention represent valuable compounds that should complement therapeutic options either as single agents or in combination with other drugs.

Endometriosis affects 5-10% of women of reproductive age and is defined as the growth of endometrial tissue in ectopic locations, found primarily within the pelvic cavity. This extra-uterine growth is accompanied by infiltration of pro-inflammatory macrophages as cardinal sign of disease leading to a chronically inflamed microenvironment and contributing to chronic pain symptoms.

However, treatment options are both limited and unsatisfactory today, leaving a demand for providing better treatment options in terms of efficacy, sustainability, reduced side effects, patient compliance and the like.

SUMMARY

The present invention covers compounds of general formula (I) which are antagonists of the TRPA1 receptors.

General formula (I) is defined below.

However, the state of the art does not describe the compounds of general formula (I) of the present invention as described and defined herein. The compounds of the present invention have surprising and advantageous properties as potent antagonists of the TRPA1 receptors.

In particular, the compounds of the present invention have surprisingly been found to effectively inhibit TRPA1 receptors for which data are given in biological experimental section and provide therefore pharmacological rationale for the treatment or prophylaxis of diseases associated with pain and inflammation, in particular in mammals, such as but not limited for the treatment or prophylaxis of pain-related/associated diseases, conditions and disorders and pain syndromes, gynecological diseases, urinary tract disorders and diseases, cancer and cancer-related pain, neurological disorders, respiratory disorders, gastrointestinal disorders, metabolic disorders, neurodegenerative disorders, skin disorders, cardiovascular disorders and inflammatory diseases.

DESCRIPTION of the INVENTION

In accordance with a first aspect, the present invention covers compounds of general formula (l): in which: m represents 1 or 2; and general formula (I) is selected from the group consisting of: in which:

R ¹ represents hydrogen or halogen; R ² represents hydrogen or halogen;

R ³ represents hydrogen or fluoro;

R ⁴ represents hydrogen or fluoro; and hydrates, solvates, and salts thereof, and mixtures of same. In accordance with a second embodiment of the first aspect, the present invention covers compounds of general formula (I), supra, in which: m represents 1 or 2; and general formula (I) is selected from the group consisting of: in which:

R ¹ represents hydrogen, fluoro, chloro, or bromo;

R ² represents hydrogen, fluoro, chloro, or bromo;

R ³ represents hydrogen or fluoro;

R ⁴ represents hydrogen or fluoro; and hydrates, solvates, and salts thereof, and mixtures of same.

In accordance with a third embodiment of the first aspect, the present invention covers compounds of general formulae (la) and (lb): in which:

R ¹ represents hydrogen, fluoro, or chloro;

R ² represents hydrogen, fluoro, or chloro; and hydrates, solvates, and salts thereof, and mixtures of same.

In accordance with a forth embodiment of the first aspect, the present invention covers compounds of general formulae (Ic) and (Id): in which: R ¹ represents hydrogen, fluoro, chloro, or bromo;

R ² represents hydrogen, fluoro, chloro, or bromo;

R ³ represents hydrogen or fluoro;

R ⁴ represents hydrogen or fluoro; and hydrates, solvates, and salts thereof, and mixtures of same.

It is to be understood that the present invention relates also to any combination of the preferred embodiments or features described above in respect of compounds of formulae (la), (lb), (Ic), or (Id) as described herewith.

In accordance with a second aspect, the present invention covers a compound of general formula (la), (lb), (Ic), or (Id) as disclosed above or hydrates, solvates, and salts thereof, and mixtures of same for use in the treatment or prophylaxis of a disease.

In other words, the invention is directed to a method for the treatment and/or prophylaxis of a disease comprising the step of administrating to a patient in need a compound of general formula (la), (lb), (Ic), or (Id) as disclosed above, or the invention is directed to the use of a compound of general formula (la), (lb), (Ic), or (Id) as disclosed above for treatment or prophylaxis of a disease or the invention is directed to the use of compound of general formula (la), (lb), (Ic), or (Id) as disclosed above for manufacturing pharmaceutical compositions for the treatment or prophylaxis of diseases.

The disease is preferably selected from the list of;

• Pain-related/associated diseases, conditions and disorders and pain syndromes;

• Gynecological diseases;

• Urinary tract disorders and diseases;

• Cancer and cancer-related pain;

• Neurological disorders;

• Respiratory disorders;

• Gastrointestinal disorders;

• Metabolic disorders;

• Neurodegenerative disorders;

• Skin disorders;

• Cardiovascular disorders and;

• Inflammatory diseases.

→ Pain syndromes include but are not limited to acute, chronic, inflammatory and neuropathic pain. Pain syndromes are preferably selected from inflammatory pain, low back pain surgical pain, visceral pain, dental pain, periodontitis, premenstrual pain, endometriosis-associated pain, pain associated with fibrotic diseases, central pain, pain due to burning mouth syndrome, pain due to burns, pain due to migraine, cluster headaches, pain due to nerve injury, pain due to neuritis, neuralgias, pain due to poisoning, pain due to ischemic injury, pain due to interstitial cystitis, cancer pain, pain due to viral, parasitic or bacterial infections, pain due to traumatic nerve-injury, pain due to post-traumatic injuries (including fractures and sport injuries), pain due to trigeminal neuralgia, pain associated with small fiber neuropathy, pain associated with diabetic neuropathy, pain following surgical (post-operative pain), postherpetic neuralgia, chronic lower back pain, neck pain phantom limb pain, pelvic pain syndrome, chronic pelvic pain, neuroma pain, complex regional pain syndrome, pain associated with gastrointestinal distension, chronic arthritic pain and related neuralgias, and pain associated with cancer, Morphine-resistant pain, pain associated with chemotherapy, HIV and HIV treatment-induced neuropathy; and pain associated with diseases or disorders selected from the group consisting of hyperalgesia, allodynia, functional bowel disorders (such as irritable bowel syndrome) and arthritis (such as osteoarthritis, rheumatoid arthritis and ankylosing spondylitis).

Pain-associated diseases or disorders include but are not limited to hyperalgesia, allodynia, functional bowel disorders (such as irritable bowel syndrome), gout, arthritis (such as osteoarthritis), rheumatoid arthritis and ankylosing spondylitis), burning mouth syndrome, burns, migraine or cluster headaches, nerve injury, traumatic nerve injury, post-traumatic injuries (including fractures and sport injuries), neuritis, neuralgias, poisoning, ischemic injury, interstitial cystitis, cancer, trigeminal neuralgia, small fiber neuropathy, diabetic neuropathy, chronic arthritis and related neuralgias, HIV and HIV treatment-induced neuropathy, pruritus; impaired wound healing and disease of the skeleton like degeneration of the joints. Gynecological diseases include but are not limited to primary and secondary dysmenorrhea, dyspareunia, vulvudynia, endometriosis, adenomyosis, endometriosis-associated pain, endometriosis-associated symptoms, wherein said symptoms are in particular abdominal pain, dysmenorrhea, dyspareunia, dysuria, dyschezia or pelvic hypersensitivity, uterine fibroids, or uterine fibroids associated pain symptoms.

Urinary tract diseases or disorders include but are not limited to disorders and diseases associated with bladder outlet obstruction; urinary incontinence conditions such as reduced bladder capacity, increased frequency of micturition, urge incontinence, stress incontinence, or bladder hyper reactivity; benign prostatic hypertrophy; prostatic hyperplasia; prostatitis; detrusor hyperreflexia; overactive urinary bladder and symptoms related to overactive urinary bladder wherein said symptoms are in particular increased urinary frequency, nocturia, urinary urgency or urge incontinence; pelvic hypersensitivity; urethritis; prostatitis; prostatodynia; cystitis, in particular interstitial cystitis; idiopathic bladder hypersensitivity; kidney disease as hyperprostaglandin E syndrome, and classic Bartter syndrome. → Cancer and cancer-related pain include but are not limited to, for example: solid tumours, such as cancers of the breast, respiratory tract, brain, reproductive organs, digestive tract, urinary tract, eye, liver, skin, head and neck, thyroid, parathyroid and their distant metastases. Those disorders also include lymphomas, sarcomas, and leukaemias. Examples of breast cancers include, but are not limited to, invasive ductal carcinoma, invasive lobular carcinoma, and ductal carcinoma in situ, and lobular carcinoma in situ. Examples of cancers of the respiratory tract include, but are not limited to, small-cell and non-small-cell lung carcinoma, as well as bronchial adenoma and pleuropulmonary blastoma. Examples of brain cancers include, but are not limited to, brain stem and hypophtalmic glioma, cerebellar and cerebral astrocytoma, medulloblastoma, ependymoma, as well as neuroectodermal and pineal tumour. Tumours of the male reproductive organs include, but are not limited to, prostate and testicular cancer. Tumours of the female reproductive organs include, but are not limited to, endometrial, cervical, ovarian, vaginal, and vulvar cancer, as well as sarcoma of the uterus. Tumours of the digestive tract include, but are not limited to, anal, colon, colorectal, oesophageal, gallbladder, gastric, pancreatic, rectal, small- intestine, and salivary gland cancers. Tumours of the urinary tract include, but are not limited to, bladder, penile, kidney, and renal pelvis, ureter, urethral and human papillary renal cancers. Eye cancers include, but are not limited to, intraocular melanoma and retinoblastoma. Examples of liver cancers include, but are not limited to, hepatocellular carcinoma (liver cell carcinomas with or without fibrolamellar variant), cholangiocarcinoma (intrahepatic bile duct carcinoma), and mixed hepatocellular cholangiocarcinoma. Skin cancers include, but are not limited to, squamous cell carcinoma, Kaposi's sarcoma, malignant melanoma, Merkel cell skin cancer, and non-melanoma skin cancer. Head-and-neck cancers include, but are not limited to, laryngeal, hypopharyngeal, nasopharyngeal, oropharyngeal cancer, lip and oral cavity cancer and squamous cell. Lymphomas include, but are not limited to, AIDS-related lymphoma, non-Hodgkin's lymphoma, cutaneous T-cell lymphoma, Burkitt lymphoma, Hodgkin's disease, and lymphoma of the central nervous system. Sarcomas include, but are not limited to, sarcoma of the soft tissue, osteosarcoma, malignant fibrous histiocytoma, lymphosarcoma, and rhabdomyosarcoma. Leukemias include, but are not limited to, acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, and hairy cell leukemia.

→ Neurological disorders include but are not limited to epilepsy, partial and generalized seizures, addiction, encephalitis, fibromyalgia, Amyotrophic lateral sclerosis, anxiety disorders including generalized anxiety disorder and depression disorders,

→ Respiratory disorders include but are not limited to asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, interstitial pulmonary fibrosis, bronchospasm, chronic chough, persistent chronic chough, refractory chronic cough and idiopathic chronic cough.

→ Gastrointestinal disorders include but are not limited to irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), biliary colic and other biliary disorders, renal colic, diarrhea-dominant IBS; gastroesophageal reflux, gastrointestinal distension, Crohn's disease and the like.

→ Metabolic disorders include but are not limited to fatty liver disorders, NASH (Non- Alcoholic Steato-Hepatitis); fibrotic diseases including lung fibrosis, heart fibrosis, kidney fibrosis and fibrosis of other organs; metabolic syndrome including, for example, insulin resistance, hypertension, refractory hypertension, dyslipoproteinaemia and obesity, diabetes mellitus, in particular Diabetes type II, myocardial infarction; atherosclerosis; lipid disorders and polycystic ovary syndrome.

→ Neurodegenerative disorders include but are not limited to Alzheimer's disease, Multiple Sclerosis, Parkinson's disease, brain ischemia, traumatic brain injury and spinal cord injury.

→ Skin disorders include but are not limited to atopic dermatitis, psoriasis, pruritus, itch and rosacea.

→ Cardiovascular disorders include but are not limited to ischemia reperfusion injury, cardiac ischemia, myocardial infarction, stroke, heart failure, hypertensive diseases, thromboembolic disease and thrombosis.

→ Inflammatory diseases, disorders or conditions include but are not limited to acute, chronic, ulcerative, fibrotic, allergic and auto-immune diseases, infection by pathogens, immune reactions due to hypersensitivity, entering foreign bodies, physical injury, necrosis, surgical or dental procedures, arthritis, osteoarthritis, juvenile arthritis, rheumatoid arthritis, juvenile onset rheumatoid arthritis, rheumatic fever, ankylosing spondylitis, Hodgkin's disease, systemic lupus erythematosus, vasculitis, pancreatitis, nephritis, bursitis, conjunctivitis, iritis, scleritis, uveitis, wound healing, dermatitis, eczema, stroke, diabetes mellitus, autoimmune diseases, allergic disorders, rhinitis, ulcers, mild to moderately active ulcerative colitis, familial adenomatous polyposis, coronary heart disease, sarcoidosis and any other disease with an inflammatory component.

Preferably, the disease is selected from the treatment or prophylaxis of pain syndromes and pain associated disease (acute and chronic), inflammatory-induced pain disorders, neuropathic pain disorders, pelvic pain, visceral pain, cancer-associated pain, endometriosis-associated pain as well as endometriosis as such, cancer as such, respiratory diseases as such, urinary tract diseases as such neurological and neurodegenerative disorders as such, metabolic disorders as such, gastrointestinal disorders as such, cancer as such, inflammatory diseases as such, cardiovascular disorder as such and skin diseases.

More preferably, the disease is selected from pain-related/associated diseases, conditions and disorders and pain syndrome, dysmenorrhea, dyspareunia, dysuria, dyschezia, endometriosis, endometriosis-associated pain and endometriosis-associated symptoms.

Even more preferably, the disease is selected from endometriosis, endometriosis- associated pain and endometriosis-associated symptoms.

The compounds of the present invention can be used in particular in therapy and prevention, i.e. prophylaxis, of endometriosis, endometriosis-associated pain and endometriosis-associated symptoms.

Conventional methods for preparing such pharmaceutical compositions in appropriate dosage forms are known.

In accordance with a third aspect, the present invention covers pharmaceutical compositions comprising compound(s) of formulae (la), (lb), (lc), and (Id) as disclosed above and one or more pharmaceutically acceptable excipients. Pharmaceutically acceptable excipient is defined as a filler (such as sugars, such as lactose, sucrose, dextrose and dextrates; sugar alcohols, such as mannitol, sorbitol and xylitol); carbonates and phosphates of alkaline earth metals, such as calcium carbonate and calcium phosphate; celluloses, such as powdered cellulose and microcrystalline cellulose; colloidal silica; titanium dioxide; kaolin; talc), lubricants (such as magnesium stearate), carrier substances (for example microcrystalline cellulose, lactose, mannitol), solvents (e.g. liquid polyethylene glycols), emulsifiers and dispersants or wetting agents (for example sodium dodecylsulphate, polyoxysorbitan oleate), binders (for example polyvinylpyrrolidone), synthetic and natural polymers (for example albumin), stabilizers (e.g. antioxidants, for example ascorbic acid), colouring matter (e.g. inorganic pigments, for example iron oxides) and taste and/or odour correctants.

Preferably, the pharmaceutically acceptable excipient is a filler or a binder.

The present invention furthermore covers pharmaceutical compositions, in particular medicaments, which comprise at least one compound according to the invention, conventionally together with one or more pharmaceutically suitable excipients, and to their use for the above mentioned purposes.

The present invention covers the intermediate compounds which are disclosed in the Example Section of this text, infra.

In accordance with a fourth aspect, the present invention covers an antagonist or inhibitor of Transient Receptor Potential Ankyrin 1 (TRPA1) for use in the treatment and/or prevention of patient in need

• suffering from,

• at risk of developing, and/or

• being diagnosed for dysmenorrhea, dyspareunia, dysuria, dyschezia, endometriosis, endometriosis- associated pain or endometriosis-associated symptoms, preferably endometriosis, endometriosis-associated pain or endometriosis-associated symptoms.

In other words, the present invention covers an antagonist or inhibitor of Transient Receptor Potential Ankyrin 1 (TRPA1) for use in the treatment or prophylasis of a disease selected from dysmenorrhea, dyspareunia, dysuria, dyschezia, endometriosis, endometriosis-associated pain or endometriosis-associated symptoms, preferably endometriosis, endometriosis-associated pain or endometriosis-associated symptoms. The inventors of the present invention found, surprisingly, that TRPA1 is expressed in inflammatory cell types and in diseased tissue of endometriosis patients, and also showed that TRPA1 inhibition shall present an alleviating effect on these conditions, such dysmenorrhea, dyspareunia, dysuria, dyschezia, endometriosis, endometriosis ^» associated pain or endometriosis-associated symptoms like inflammatory pain. In a particular embodiment, the antagonist or inhibitor is for treating endometriosis, endometriosis-associated pain or endometrioses-associated symptoms like inflammatory pain.

As used herein, the term “antagonist or inhibitor of TRPA1” refers to a compound that is capable of reducing or inhibiting either directly or indirectly the activity of TRPA1, preferably by at least 20%, preferably by at least 50%, more preferably by at least 75%. Suitable assays to determine said inhibition or reduction are readily available to the skilled person from the pertinent literature.

DEFINITIONS

The term “substituted” means that one or more hydrogen atoms on the designated atom or group are replaced with a selection from the indicated group, provided that the designated atom's normal valency under the existing circumstances is not exceeded. Combinations of substituents and/or variables are permissible.

As used herein, the term “one or more”, e.g. in the definition of the substituents of the compounds of general formula (I) of the present invention, means “1 , 2, 3, 4 or 5, particularly 1, 2, 3 or 4, more particularly 1 , 2 or 3, even more particularly 1 or 2”.

The term “comprising” when used in the specification includes “consisting of”.

If within the present text any item is referred to as “as mentioned herein”, it means that it may be mentioned anywhere in the present text.

The terms as mentioned in the present text have the following meanings:

The term “halogen” or “halogen atom” means a fluorine, chlorine, bromine or iodine atom, particularly fluorine, chlorine or bromine atom.

Where the plural form of the word compounds, salts, polymorphs, hydrates, solvates and the like, is used herein, this is taken to mean also a single compound, salt, polymorph, isomer, hydrate, solvate or the like. The compounds of the present invention contain asymmetric centres. It is possible that one or more asymmetric carbon atoms are present in the (R) or (S) configuration, which can result in diastereomeric mixtures in the case of multiple asymmetric centres. In certain instances, it is possible that asymmetry also be present due to restricted rotation about a given bond, for example, the central bond adjoining two substituted aromatic rings of the specified compounds.

Preferred compounds are those which produce the more desirable biological activity. Separated, pure or partially purified isomers and stereoisomers or racemic or diastereomeric mixtures of the compounds of the present invention are also included within the scope of the present invention. The purification and the separation of such materials can be accomplished by standard techniques known in the art.

If only one isomer (enantiomer/diastereomer) displays the desired biological activity, and the second isomer (enantiomer/diastereomer) is inactive: Preferred isomers are those which produce the more desirable biological activity. These separated, pure or partially purified isomers or racemic mixtures of the compounds of this invention are also included within the scope of the present invention. The purification and the separation of such materials can be accomplished by standard techniques known in the art.

The optical isomers can be obtained by resolution of the racemic mixtures according to conventional processes, for example, by the formation of diastereoisomeric salts using an optically active acid or base or formation of covalent diastereomers. Examples of appropriate acids are tartaric, diacetyl tartaric, ditoluoyltartaric and camphorsulfonic acid. Mixtures of diastereoisomers can be separated into their individual diastereomers on the basis of their physical and/or chemical differences by methods known in the art, for example, by chromatography or fractional crystallisation. The optically active bases or acids are then liberated from the separated diastereomeric salts, A different process for separation of optical isomers involves the use of chiral chromatography (e.g., HPLC columns using a chiral phase), with or without conventional derivatisation, optimally chosen to maximise the separation of the enantiomers. Suitable HPLC columns using a chiral phase are commercially available, such as those manufactured by Daicel, e.g,, Chiracel OD and Chiracel OJ, for example, among many others, which are all routinely selectable. Enzymatic separations, with or without derivatisation, are also useful. The optically active compounds of the present invention can likewise be obtained by chiral syntheses utilizing optically active starting materials.

In order to distinguish different types of isomers from each other reference is made to IUPAC Rules Section E (Pure Appl Chem 45, 11-30, 1976). The present invention includes all possible stereoisomers of the compounds of the present invention as single stereoisomers, or as any mixture of said stereoisomers, e.g. (R)- or (S)- isomers, in any ratio. Isolation of a single stereoisomer, e.g. a single enantiomer or a single diastereomer, of a compound of the present invention is achieved by any suitable state of the art method, such as chromatography, especially chiral chromatography, for example.

The present invention also covers useful forms of the compounds of the present invention, such as metabolites, hydrates, solvates, prodrugs, salts, in particular pharmaceutically acceptable salts, and/or co-precipitates.

The compounds of the present invention can exist as a hydrate, or as a solvate, wherein the compounds of the present invention contain polar solvents, in particular water, methanol or ethanol for example, as structural element of the crystal lattice of the compounds. It is possible for the amount of polar solvents, in particular water, to exist in a stoichiometric or non-stoichiometric ratio. In the case of stoichiometric solvates, e.g. a hydrate, hemi-, (semi-), mono-, sesqui-, di-, tri-, tetra-, penta- etc. solvates or hydrates, respectively, are possible. The present invention includes all such hydrates or solvates.

Further, it is possible for the compounds of the present invention to exist in free form, e.g. as a free base, or as a free acid, or as a zwitterion, or to exist in the form of a salt. Said salt may be any salt, either an organic or inorganic addition salt, particularly any pharmaceutically acceptable organic or inorganic addition salt, which is customarily used in pharmacy, or which is used, for example, for isolating or purifying the compounds of the present invention.

The term “pharmaceutically acceptable salt" refers to an inorganic or organic acid addition salt of a compound of the present invention. For example, see S. M. Berge, et al. “Pharmaceutical Salts,” J. Pharm. Sci. 1977, 66, 1-19.

A suitable pharmaceutically acceptable salt of the compounds of the present invention may be, for example, an acid-addition salt of a compound of the present invention bearing a nitrogen atom, in a chain or in a ring, for example, which is sufficiently basic, such as an acid-addition salt with an inorganic acid, or “mineral acid”, such as hydrochloric, hydrobromic, hydroiodic, sulfuric, sulfamic, bisulfuric, phosphoric, or nitric acid, for example, or with an organic acid, such as formic, acetic, acetoacetic, pyruvic, trifluoroacetic, propionic, butyric, hexanoic, heptanoic, undecanoic, lauric, benzoic, salicylic, 2-(4-hydroxybenzoyl)-benzoic, camphoric, cinnamic, cyclopentanepropionic, digluconic, 3-hydroxy-2-naphthoic, nicotinic, pamoic, pectinic, 3-phenylpropionic, pivalic, 2-hydroxyethanesulfonic, itaconic, trifluoromethanesulfonic, dodecylsulfuric, ethanesulfonic, benzenesulfonic, para-toluenesulfonic, methanesulfonic, 2-naphthaIenesuIfonic, naphthalinedisulfonic, camphorsulfonic acid, citric, tartaric, stearic, lactic, oxalic, malonic, succinic, malic, adipic, alginic, maleic, fumaric, D-gluconic, mandelic, ascorbic, glucoheptanoic, glycerophosphoric, aspartic, sulfosalicylic, or thiocyanic acid, for example.

Further, another suitably pharmaceutically acceptable salt of a compound of the present invention which is sufficiently acidic, is an alkali metal salt, for example a sodium or potassium salt, an alkaline earth metal salt, for example a calcium, magnesium or strontium salt, or an aluminium or a zinc salt, or an ammonium salt derived from ammonia or from an organic primary, secondary or tertiary amine having 1 to 20 carbon atoms, such as ethylamine, diethylamine, triethylamine, ethyldiisopropylamine, monoethanolamine, diethanolamine, triethanolamine, dicyclohexylamine, dimethylaminoethanol, diethylaminoethanol, tris(hydroxymethyl)aminomethane, procaine, dibenzylamine, N-methylmorpholine, arginine, lysine, 1,2-ethylenediamine, N- methylpiperidine, N-methyl-glucamine, N,N-dimethyl-glucamine, N-ethyl-glucamine, 1 ,6- hexanediamine, glucosamine, sarcosine, serinol, 2-amino-1, 3-propanediol, 3-amino-1,2- propanediol, 4-amino-1,2,3-butanetriol, or a salt with a quarternary ammonium ion having 1 to 20 carbon atoms, such as tetramethylammonium, tetraethylammonium, tetra(n- propyl)ammonium, tetra(n-butyl)ammonium, N-benzyl- N,N,N-trimethylammonium, choline or benzalkonium.

Those skilled in the art will further recognise that it is possible for acid addition salts of the claimed compounds to be prepared by reaction of the compounds with the appropriate inorganic or organic acid via any of a number of known methods. Alternatively, alkali and alkaline earth metal salts of acidic compounds of the present invention are prepared by reacting the compounds of the present invention with the appropriate base via a variety of known methods.

The present invention includes all possible salts of the compounds of the present invention as single salts, or as any mixture of said salts, in any ratio.

In the present text, in particular in the Experimental Section, for the synthesis of intermediates and of examples of the present invention, when a compound is mentioned as a salt form with the corresponding base or acid, the exact stoichiometric composition of said salt form, as obtained by the respective preparation and/or purification process, is, in most cases, unknown.

Unless specified otherwise, suffixes to chemical names or structural formulae relating to salts, such as "hydrochloride", "trifluoroacetate", "sodium salt", or "x HCI", "x CF ₃ COOH", "x Na ⁺ ", for example, mean a salt form, the stoichiometry of which salt form not being specified.

This applies analogously to cases in which synthesis intermediates or example compounds or salts thereof have been obtained, by the preparation and/or purification processes described, as solvates, such as hydrates, with (if defined) unknown stoichiometric composition.

The term “treating” or “treatment” as used in the present text is used conventionally, e.g., the management or care of a subject for the purpose of combating, alleviating, reducing, relieving, improving the condition of a disease or disorder, such as a carcinoma,

SCHEMES

The compounds according to the invention of general formula (I) can be prepared according to the following schemes 1 to 2. The schemes and procedures described below illustrate synthetic routes to the compounds of general formula (I) of the invention and are not intended to be limiting. It is dear to the person skilled in the art that the order of transformations, separations of enantiomers, as exemplified in schemes 1 to 2 can be modified in various ways. The order of transformations exemplified in these schemes is therefore not intended to be limiting. Specific examples are described in the subsequent paragraphs.

The starting materials are either commercially available or can be prepared according to procedures available from the public domain, as understandable to the person skilled in the art. Specific examples are described in the Experimental Section.

Scheme 1 describes the preparation of trans-isomers of general formulae (la) and (lb) with the meaning of R ¹ and R ² as defined in general formula (I) supra.

The introduction of the trifluoromethyl group (step a) can be achieved by reacting cydopentanone (II) with Me ₃ Si-CF ₃ or Et ₃ Si-CF ₃ and tetra-n-butylammonium fluoride in tetrahydrofuran at between 0 °C and RT to give racemic tertiary alcohol rac-(lll). The following dehydration reaction (step b) can be performed, for example, by using thionyl chloride in presence of dimethylamino pyridine and pyridine between RT and 45 °C to access alkene (IV). Other dehydrating agents, for instance, Burgess reagent or cyanuric chloride can also be used in such reaction which is known by the person skilled in the art. Epoxidation reaction (step c) of alkene (IV) to epoxide rac-(V) can be achieved by the usage of oxidizing agents, such as meta-chloroperbenzoic acid (mCPBA) or hydrogenperoxide in dichloromethane at RT. Epoxide opening reaction (step d) of epoxide rac-(V) can be achieved using scandium-(lll)-trifluoromethanesulfonate as a Lewis acid in toluene, in presence of the desired nucleophilic aniline at 60 °C to give access to compounds of general formulae (la) and (lb). The enantiomers can be separated by methods known to the person skilled in the art. Other alternative methods/routes known to the person skilled in the art can also be utilized to access compounds of general formulae (la) and (lb) and it is not limited to the conditions listed above.

Scheme 1

Me ₃ Si-CF ₃ or Et ₃ Si-CF ₃ , tetra-n-butylammonium fluoride, THF, -40 °C to RT; b) Dehydration; c) Epoxidation; d) Anilines, Sc(lll)(SO ₃ CF ₃ ) ₃ , PhMe, 40 °C

Scheme 2 describes the preparation of trans-isomers of general formulae (Ic) and (Id) with the meaning of R ¹ , R ² , R ³ and R ⁴ as defined in general formula (I) supra.

The introduction of trifluoromethyl group (step a) can be achieved by reacting compounds of general formula (VI) with Me ₃ Si-CF ₃ or Et ₃ Si-CF ₃ and tetra-n-butylammonium fluoride in tetrahydrofuran at between 0 °C to RT to give racemic alcohols of general formula rac- (VII), The following dehydration reaction (step b) can be performed, for example, using thionyl chloride in presence of dimethylamino pyridine and pyridine between RT to 45 °C to access alkenes of general formula (VIII). Other dehydrating agents, for instance, Burgess reagent or cyanuric chloride can also be used in this reaction which is clear to the person skilled in the art. Epoxidation reaction (step c) of alkenes with general formula (VIII) to epoxides of general formula rac-(IX) can be achieved by the usage of oxidizing agents, such as meta-chloroperbenzoic acid (mCPBA) or hydrogenperoxide in dichloromethane at RT. Epoxide opening reaction (step d) of epoxides of general formula rac-(IX) can be achieved using scandium-(III)-trifIuoromethanesulfonate as a Lewis acid in toluene, in presence of the desired nucleophilic anilines at 60 °C to give access to compounds of general formula (Ic) and (Id), after separation of enantiomers by methods known to the person skilled in the art. Other alternative methods/routes known to the person skilled in the art can also be utilized to access compounds of general formulae (Ic) and (Id) and it is not limited to conditions listed above.

Scheme 2 a) Me ₃ Si-CF ₃ or Et ₃ Si-CF ₃ , tetra-n-butylammonium fluoride, THF, -40 °C to RT; b) Dehydration; c) Epoxidation; d) Anilines, Sc(III)(SO ₃ CF ₃ ) ₃ , PhMe, 40 °C

It Is possible for the compounds according to the invention to have systemic and/or local activity. For this purpose, they can be administered in a suitable manner, such as, for example, via the oral, parenteral, pulmonary, nasal, sublingual, lingual, buccal, rectal, vaginal, dermal, transdermal, conjunctival, otic route or as an implant or stent.

For these administration routes, it is possible for the compounds according to the invention to be administered in suitable administration forms.

For oral administration, it is possible to formulate the compounds according to the invention to dosage forms known in the art that deliver the compounds of the invention rapidly and/or in a modified manner, such as, for example, tablets (uncoated or coated tablets, for example with enteric or controlled release coatings that dissolve with a delay or are insoluble), orally-disintegrating tablets, films/wafers, films/lyophylisates, capsules (for example hard or soft gelatine capsules), sugar-coated tablets, granules, pellets, powders, emulsions, suspensions, aerosols or solutions. It is possible to incorporate the compounds according to the invention in crystalline and/or amorphised and/or dissolved form into said dosage forms.

Parenteral administration can be effected with avoidance of an absorption step (for example intravenous, intraarterial, intracardial, intraspinal or intralumbal) or with inclusion of absorption (for example intramuscular, subcutaneous, intracutaneous, percutaneous or intraperitoneal). Administration forms which are suitable for parenteral administration are, inter alia, preparations for injection and infusion in the form of solutions, suspensions, emulsions, lyophylisates or sterile powders.

Examples which are suitable for other administration routes are pharmaceutical forms for inhalation [inter alia powder inhalers, nebulizers], nasal drops, nasal solutions, nasal sprays; tablets/films/wafers/capsules for lingual, sublingual or buccal administration; suppositories; eye drops, eye ointments, eye baths, ocular inserts, ear drops, ear sprays, ear powders, ear-rinses, ear tampons; vaginal capsules, aqueous suspensions (lotions, mixturae agitandae), lipophilic suspensions, emulsions, ointments, creams, transdermal therapeutic systems (such as, for example, patches), milk, pastes, foams, dusting powders, implants or stents.

The compounds according to the invention can be incorporated into the stated administration forms. This can be effected in a manner known per se by mixing with pharmaceutically suitable excipients. Pharmaceutically suitable excipients include, inter alia,

• fillers and carriers (for example cellulose, microcrystalline cellulose (such as, for example, Avicel ^® ), lactose, mannitol, starch, calcium phosphate (such as, for example, Di-Cafos ^® )),

• ointment bases (for example petroleum jelly, paraffins, triglycerides, waxes, wool wax, wool wax alcohols, lanolin, hydrophilic ointment, polyethylene glycols),

• bases for suppositories (for example polyethylene glycols, cacao butter, hard fat),

• solvents (for example water, ethanol, isopropanol, glycerol, propylene glycol, medium chain-length triglycerides fatty oils, liquid polyethylene glycols, paraffins), • surfactants, emulsifiers, dispersants or wetters (for example sodium dodecyl sulfate), lecithin, phospholipids, fatty alcohols (such as, for example, Lanette ^® ), sorbitan fatty acid esters (such as, for example, Span ^® ), polyoxyethylene sorbitan fatty acid esters (such as, for example, Tween ^® ), polyoxyethylene fatty acid glycerides (such as, for example, Cremophor ^® ), polyoxethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, glycerol fatty acid esters, poloxamers (such as, for example, Pluronic ^® ),

• buffers, acids and bases (for example phosphates, carbonates, citric acid, acetic acid, hydrochloric acid, sodium hydroxide solution, ammonium carbonate, trometamol, triethanolamine),

• isotonicity agents (for example glucose, sodium chloride),

• adsorbents (for example highly-disperse silicas),

• viscosity-increasing agents, gel formers, thickeners and/or binders (for example polyvinylpyrrolidone, methylcellulose, hydroxypropylmethylcellulose, hydroxypropylcellulose, carboxymethylcellulose-sodium, starch, carbomers, polyacrylic acids (such as, for example, Carbopol ^® ); alginates, gelatine),

• disintegrants (for example modified starch, carboxymethylcellulose-sodium, sodium starch glycolate (such as, for example, Explotab ^® ), cross- linked polyvinylpyrrolidone, croscarmellose-sodium (such as, for example, AcDiSol ^® )),

• flow regulators, lubricants, glidants and mould release agents (for example magnesium stearate, stearic acid, talc, highly-disperse silicas (such as, for example, Aerosil ^® )),

• coating materials (for example sugar, shellac) and film formers for films or diffusion membranes which dissolve rapidly or in a modified manner (for example polyvinylpyrrolidones (such as, for example, Kollidon ^® ), polyvinyl alcohol, hydroxypropylmethylcellulose, hydroxypropylcellulose, ethylcellulose, hydroxypropylmethylcellulose phthalate, cellulose acetate, cellulose acetate phthalate, polyacrylates, polymethacrylates such as, for example, Eudragit ^® )),

• capsule materials (for example gelatine, hydroxypropylmethylcellulose),

• synthetic polymers (for example polylactides, polyglycolides, polyacrylates, polymethacrylates (such as, for example, Eudragit ^® ), polyvinylpyrrolidones (such as, for example, Kollidon ^® ), polyvinyl alcohols, polyvinyl acetates, polyethylene oxides, polyethylene glycols and their copolymers and blockcopolymers),

• plasticizers (for example polyethylene glycols, propylene glycol, glycerol, triacetine, triacetyl citrate, dibutyl phthalate),

• penetration enhancers,

• stabilisers (for example antioxidants such as, for example, ascorbic acid, ascorbyl palmitate, sodium ascorbate, butylhydroxyanisole, butylhydroxytoluene, propyl gal late),

• preservatives (for example parabens, sorbic acid, thiomersal, benzalkonium chloride, chlorhexidine acetate, sodium benzoate),

• colourants (for example inorganic pigments such as, for example, iron oxides, titanium dioxide),

• flavourings, sweeteners, flavour- and/or odour-masking agents.

The present invention furthermore relates to a pharmaceutical composition which comprise at least one compound according to the invention, conventionally together with one or more pharmaceutically suitable excipient(s), and to their use according to the present invention.

EXPERIMENTAL SECTION GENERAL PART

Chemical names were generated using the ACD/Name software from ACD/Labs. In some cases generally accepted names of commercially available reagents were used in place of ACD/Name generated names.

The following table lists the abbreviations used in this paragraph and in the Examples section as far as they are not explained within the text body. Other abbreviations have their meanings customary perse to the skilled person.

The various aspects of the invention described in this application are illustrated by the following examples which are not meant to limit the invention in any way. The example testing experiments described herein serve to illustrate the present invention and the invention is not limited to the examples given.

EXPERIMENTAL SECTION - CHEMISTRY All reagents, for which the synthesis is not described in the experimental part, are either commercially available, or are known compounds or may be formed from known compounds by known methods by a person skilled in the art.

The compounds and intermediates produced according to the methods of the invention may require purification. Purification of organic compounds is well known to the person skilled in the art and there may be several ways of purifying the same compound. In some cases, no purification may be necessary. In some cases, the compounds may be purified by crystallization. In some cases, impurities may be stirred out using a suitable solvent. In some cases, the compounds may be purified by chromatography, particularly flash column chromatography, using for example prepacked silica gel cartridges, e.g. Biotage SNAP cartidges KP-Sil ^® or KP-NH ^® in combination with a Biotage autopurifier system (SP4 ^® or Isolera Four ^® ) and eluents such as gradients of hexane/ethyl acetate or DCM/methanol. In some cases, the compounds may be purified by preparative HPLC using for example a Waters autopurifier equipped with a diode array detector and/or on- line electrospray ionization mass spectrometer in combination with a suitable prepacked reverse phase column and eluents such as gradients of water and acetonitrile which may contain additives such as trifluoroacetic acid, formic acid or aqueous ammonia.

In some cases, purification methods as described above can provide those compounds of the present invention which possess a sufficiently basic or acidic functionality in the form of a salt, such as, in the case of a compound of the present invention which is sufficiently basic, a trifluoroacetate or formate salt for example, or, in the case of a compound of the present invention which is sufficiently acidic, an ammonium salt for example. A salt of this type can either be transformed into its free base or free acid form, respectively, by various methods known to the person skilled in the art, or be used as salts in subsequent biological assays. It is to be understood that the specific form (e.g. salt, free base etc.) of a compound of the present invention as isolated and as described herein is not necessarily the only form in which said compound can be applied to a biological assay in order to quantify the specific biological activity.

Furthermore, the intermediates and examples according to the invention may be present as rotational isomers, in particular in NMR studies. In cases where the presence of rotamers are clearly visible by NMR, it is stated in the experimental section. Purity figures are generally based on corresponding peak integrations in the LC/MS chromatogram, but may additionally also have been determined with the aid of the ¹ H NMR spectrum.

In solvent-containing or contaminated batches, the formal yield may be ">100%"; in these cases the yield is not corrected for solvent or purity.

The multiplicities of proton signals in ¹ H NMR spectra reported in the paragraphs which follow represent the signal form observed in each case and do not take account of any higher-order signal phenomena. In general, the stated chemical shift refers to the centre of the signal in question. In the case of broad multiplets, an interval is given. Signals obscured by solvent or water were either tentatively assigned or have not been listed. Significantly broadened signals - caused, for example, by rapid rotation of molecular moieties or because of exchanging protons - were likewise assigned tentatively (often referred to as a broad multiplet or broad singlet or broad doublet) or are not listed.

Melting points and melting point ranges, if stated, are uncorrected.

Absolute configuration of example 16 was determined to be (1R, 2R) by comparison of experimentally measured vibrational circular dichroism (VCD) spectra with the calculated (ab initio) VCD spectrum for (1R, 2R)-2-(4-fluoroanilino)-1-(trifluoromethyl)cyclohexan-1- ol.

Analytical LC-MS methods:

Method A: Instrument: Waters Acquity UPLCMS SingleQuad; Column: Acquity UPLC BEH C18 1.7 pm, 50x2.1 mm; eluent A: water + 0.1 vol % formic acid (99%), eluent B: acetonitrile; gradient: 0-1.6 min 1-99% B, 1.6-2.0 min 99% B; flow 0.8 ml/min; temperature: 60 °C; DAD scan: 210-400 nm.

Method B: Instrument: Waters Acquity UPLCMS SingleQuad; Column: Acquity UPLC BEH C18 1.7 pm, 50x2.1mm; eluent A: water + 0.2 vol % aqueous ammonia (32%), eluent B: acetonitrile; gradient: 0-1.6 min 1-99% B, 1.6-2.0 min 99% B; flow 0.8 ml/min; temperature: 60 °C; DAD scan: 210-400 nm.

Method C: Instrument: Agilent 1290 UPLCMS 6230 TOF; column: BEH C 18 1.7 pm, 50x2.1mm; Eluent A: water + 0.05 % formic acid (99%); Eluent B: acetonitrile + 0.05 % formic acid (99%); gradient: 0-1.72-90% B, 1.7-2.090% B; flow 1.2 ml/min; temperature: 60°C; DAD scan: 190-400 nm.

Purification Methods: Biotage Isolera™ chromatography system (http://www.biotage.com/product-area/flash- purification) using pre-packed silica and pre-packed modified silica cartridges.

EXPERIMENTAL SECTION - INTERMEDIATES

Reaction times are either specified explicitly in the protocols of the experimental section, or reactions were run until completion. Chemical reactions were monitored and their completion was judged using methods well known to the person skilled in the art, such as thin layer chromatography, e.g. on plates coated with silica gel, or by LCMS methods.

Intermediate 1 1

1-(trifIuoromethyI)-6-oxabicycIo[3.1.0] hexane

Stepl) Synthesis of 1-(trifluoromethyl)cyclopentan-1-ol

A stirred solution of cyclopentanone (8.4 ml, 95 mmol) in THF (120 ml) was cooled to - 40°C and trifluoromethyltrimethylsilane (69 ml, 470 mmol, CAS 81290-20-2) was added in one portion. The mixture was allowed to warm to - 25°C, then cooled again to - 40°C. A solution of tetra-n-butyl ammoniumfluoride (95 mmol, 95 ml 1M in THF) was added drop-wise while the temperature was kept below - 30°C. The mixture was allowed to warm to rt, then the mixture was poured into sat. aqueous NH4CI solution and stirred vigorously for additional 10 min. The layers were separated and extracted twice with diethylether. The combined organic layers were washed with sat. NaHCO ₃ solution, dried with sodiumsulfate and cautiously concentrated (bath temperature 30°C). The product is volatile. 16 g (ca. 100% yield) of the crude title product were obtained and used without further purification and analytical characterization.

Step 2) Synthesis of 1-(trifIuoromethyI)cydopent-1-ene

1-(trifluoromethyl)cyclopentan-1-ol (8.0 g, 52 mmol) was dissolved at rt in dichloromethane (33 ml) and thionyl chloride (11 ml, 160 mmol) was added drop-wise. Then 4-dimethylaminopyridine (254 mg, 2.08 mmol) was added and pyridine (13 ml, 160 mmol) was added drop-wise. After 10 min stirring at rt, the mixture was stirred overnight at 45°C. After cooling to 0°C, the mixture was poured into a cooled aqueous copper(ll)sulfate solution. The mixture was extracted 3 times with dichloromethane, the combined organic layers washed with sat. NaHCO ₃ solution and water and dried with sodium sulfate. The crude product solution was directly taken to the next step,

Step3) Synthesis of 1-(trifluoromethyl)-6-oxabicyclo[3.1.0]hexane

A solution of meta-chloroperbenzoic acid (46.8 g with 77% purity, 209 mmol) in dichloromethane (170 ml) was dried with sodium sulfate and then added to the 1- (trifiuoromethyl)cyclopent-1-ene solution in dichloromethane from step 2) (52 mmol). The mixture was stirred at rt for 3 days. Then the mixture was cooled to 0°C and NaHCO ₃ solution (39% in water) was slowly added drop-wise. The formed white precipitate was filtered off, the layers separated and the organic layer washed 5 times with sat, NaHCO ₃ solution and dried with sodium sulfate. The solution was cautiously concentrated (> 270 mbar, 30 °C bath temperature) to yield 5.80 g (33.5% of theory) of the volatile title compound as a brown oil. The material was used without further purification or analytical characterization for the subsequent step.

Intermediate 2

1-(trifluoromethyl)-7-oxabicyclo[4.1.0]heptane

Stepl) Synthesis of 1-(trifl uoromethyl)cyclohexan-1-ol

A stirred solution of cyclohexanone (21 ml, 200 mmol) in THF (300 ml) was cooled to - 40°C and trifluoromethyltrimethylsilane (145 g, 1.02 mol, CAS 81290-20-2) was added in one portion. The mixture was allowed to warm to - 25°C, then cooled again to - 40°C. A solution of tetra-n-butyl ammoniumfluoride (200 mmol, 200 ml 1M in THF) was added drop-wise while the temperature was kept below - 30°C. The mixture was allowed to warm to rt, then the mixture was poured into sat, aqueous NH ₄ CI solution and stirred vigorously for additional 40 min. The layers were separated and extracted twice with diethylether. The combined organic layers were washed with sat. NaHCO ₃ solution, dried with sodiumsulfate and cautiously concentrated under reduced pressure (bath temperature 30°C). The product is volatile, 40 g (ca. 100% yield) of the crude title product were obtained and used without further purification and analytical characterization.

Step 2) Synthesis of 1-(trifluoromethyl)cyclohex-1-ene

1-(trifl uoromethyl)cyclohexan-1-ol (42 g, 255 mmol) was dissolved at rt in dichloromethane (200 ml) and thionyl chloride (56 ml, 770 mmol) was added drop-wise. Then 4-dimethylaminopyridine (1.25 g, 10.2 mmol) was added and pyridine (62 ml, 770 mmol) was added drop-wise. After 10 min stirring at rt, the mixture was stirred overnight at 45°C. After cooling to 0°C, the mixture was slowly poured into a cooled aqueous copper(ll)sulfate solution (500 ml). The mixture was extracted 3 times with dichloromethane. To the combined organic layers was added under stirring sat. NaHCO ₃ solution until the pH of the aqueous layer was >7. The phases were separated and the organic layer was washed with water and dried with sodium sulfate. The crude product solution was directly taken to the next step.

Step3) Synthesis of 1-(trifluoromethyl)-7-oxabicyclo[4.1.0]heptane

A solution of meta-chloroperbenzoic acid (141 g, 815 mmol) in dichloromethane (1.5 I) was dried with sodium sulfate and then added to the 1-(trifluoromethyl)cyclopent-1 -ene solution in dichloromethane from step 2) (255 mmol). The mixture was stirred at rt for 3 days. Then the mixture was cooled to 0°C and NaHCO ₃ solution (39% in water) was slowly added drop-wise. The formed white precipitate was filtered off, the layers separated and the organic layer washed 5 times with sat. NaHCO ₃ solution and dried with sodium sulfate. The solution was cautiously concentrated (> 50 mbar, 23 °C bath temperature) to yield 29 g (60% of theory, purity ca. 70%, containing starting material) of the volatile title compound as a brown oil. The material was used without further purification for the subsequent step. ¹ H-NMR (600 MHz, DMSO-d6) δ [ppm]: 1.21 - 1.36 (m,8H), 1.37 - 1.47 (m, 3H), 1.52 - 1.60 (m, 2H), 1.61 - 1.69 (m, 2H), 1.73 - 1.80 (m, 1H), 1.85 - 1.90 (m, 5H), 1,91 - 1.95 (m, 2H), 2.00 - 2.03 (m, 1 H), 2.05 (t, 1 H), 2.06 - 2.10 (m, 2H), 2.12 (qt, 2H), 3.54 (s, 2H), 3.57 - 3.64 (m, 1H), 4.26 (t, 1H), 6.41 (tq, 1 H); ¹³ C-NMR (150 MHz, DMSO-d6) δ [ppm]: 18.14, 18.58, 21.07, 22.87, 54.64, 56.08, 124.23.

Intermediate 3

4,4-difluoro-1-(trifluoromethyl)-7-oxabicyclo[4.1.0]hepta ne

Step 1) Synthesis of 4,4-difluoro-1-(trifluoromethyl)cyclohexanol

A stirred solution of 4,4-difluorocyclohexanone (20.0 g, 149 mmol) in THF (220 ml) was cooled to - 40°C and trifluoromethyltrimethylsilane (106 g, 746 mmol, CAS 81290-20-2) was added in one portion. The mixture was allowed to warm to - 28°C, then cooled again to - 40°C. A solution of tetra-n-butyl ammoniumfluoride (150 mmol, 150 ml 1M in THF) was added drop-wise while the temperature was kept below - 30°C. The mixture was allowed to warm to rt, then the mixture was poured into sat. aqueous NH ₄ CI solution and stirred vigorously for additional 10 min. The layers were separated and extracted twice with diethylether. The combined organic layers were dried with sodiumsulfate and cautiously concentrated under reduced pressure (bath temperature 30°C). The product is volatile. The concentrated solution was stirred for 1 h with 500 mL 3M HCI. Then the mixture was extracted four times with diethylether. The combined organic layers were washed with sat. aqueous sodium bicarbonate solution, dried with sodiumsulfate and cautiously concentrated under reduced pressure (> 100 mbar, bath temperature 30°C). to obtain 42 g of the crude title product which were used without further purification and analytical characterization.

Step 2) Synthesis of 4,4-difluoro-1-(trifluoromethyl)cyclohexene 4,4-difluoro-1-(trifluoromethyl)cyclohexanol (42 g, crude) was dissolved at rt in dichloromethane (115 ml) and thionyl chloride (32.4 ml, 444 mmol) was added drop-wise. Then 4-dimethylaminopyridine (724 mg, 5.93 mmol) was added and pyridine (36 ml, 444 mmol) was added drop-wise. After 10 min stirring at rt, the mixture was stirred overnight at 45°C. After cooling to 0°C, the mixture was slowly poured into a cooled aqueous copper(ll)sulfate solution (500 ml). The formed precipitate was filtered off, then the mixture was extracted 3 times with dichloromethane. To the combined organic layers was added under stirring sat. NaHCO ₃ solution until the pH of the aqueous layer was >7, The phases were separated and the organic layer was washed with water and dried with sodium sulfate. The crude product solution was directly taken to the next step.

Step 3) Synthesis of 4,4-difIuoro-1-(trifIuoromethyI)-7-oxabicydo[4.1.0]heptane To a solution of 4,4-difluoro-1-(trifluoromethyl)cyclohexene (ca. 1.34 mmol in 8.5 mL dichloromethane) was added at rt 2M aqueous sodium hydroxide solution (0.40 mL) and hydrogenperoxide (0.13 mL, 35% solution) The mixture was stirred at rt for 3 days. Then a sat. aqueous sodium bicarbonate solution was slowly added drop-wise and the mixture stirred for further 10 min. The mixture was extracted three times with dichloromethane and the organic layer was dried with sodium sulfate. The solution was concentrated to yield 200 mg of the crude title compound as a colorless oil. The material was used without further purification for the subsequent step. EXPERIMENTAL SECTION - EXAMPLES

General procedure A: Nucleophilic opening of epoxide with aromatic amines The crude epoxide (intermediate 1, 2, or 3 respectively, 0.3 to 60.0 mmol) and the respective amine (1.5 eq) were dissolved in toluene (40-50 eq.) at rt. Scandium-(lll)- trifluoromethanesulfonate (CAS 144026-79-9, 0.5 eq.) were added and the mixture was stirred at 60 °C for 1.5 - 5 h. Then the mixture was partitioned between water and ethyl acetate, the phases separated and the aqueous layer extracted twice with ethyl acetate. The combined organic layers were washed first twice with 1M HCI solution, then with sat. NaHCO ₃ solution and dried with sodium sulfate. The solvents were removed in vacuo and the residue was purified by Biotage Isolera™ chromatography (silica gel KP-SiL, eluting with hexane - ethyl acetate, 0 to 60%). The obtained racemic trans- configurated product was optionally separated by chiral preparative HPLC using the appropriate method to yield the respective single enantiomers.

Table 1: Examples synthesized according to general procedure A from intermediate 1 and the respective aromatic amine

Table 2: Examples synthesized according general procedure A from intermediate 2 and the respective aromatic amine

Example 40

4,4-difluoro-2-(4-fluoroanilino)-1-(trifluoromethyl)cyclo hexanol (trans)

4,4-difluoro-1-(trifluoromethyl)-7-oxabicyclo[4.1.0]hepta ne (Intermediate 3) (crude, 200 mg, 1 mmol) and 4-fluoroaniline (0.14 mL, 1.48 mmol) were dissolved in THF (5.3 mL ), Scandium(lll)trifluoromethanesulfonate (243 mg, 0,50 mmol) was added and the mixture was stirred overnight at 60 °C, Then the mixture was diluted with water and extracted three times with ethyl acetate. The combined organic layer was washed with 1M HCl solution and with sat. aqueous sodium bicarbonate solution, dried with sodium sulfate and concentrated in vacuo. The crude product was purified by chromatography (SiO ₂ , hexane/ethyl acetate 0-40%) to yield 18 mg of the title compound as an orange oil. LC-MS (Analytical method A): R _t = 1.17 min, 94% purity; MS (ESIpos): m/z = 314 [M+H] ^{+ 1} H-NMR (400 MHz, DMSO-d6) δ [ppm]: 1.82 - 1.37 (m, 6H), 3.92 - 3.97 (m, 1H), 5.10 (d, 1H), 6,43 (s, 1 H), 6.67 (dd, 2H), 6,92 (dd, 2H).

EXPERIMENTAL SECTION - BIOLOGICAL ASSAYS

Examples were tested in selected biological assays one or more times. When tested more than once, data are reported as either average values or as median values, wherein

• the average value, also referred to as the arithmetic mean value, represents the sum of the values obtained divided by the number of times tested, and

• the median value represents the middle number of the group of values when ranked in ascending or descending order. If the number of values in the data set is odd, the median is the middle value. If the number of values in the data set is even, the median is the arithmetic mean of the two middle values.

Examples were synthesized one or more times. When synthesized more than once, data from biological assays represent average values or median values calculated utilizing data sets obtained from testing of one or more synthetic batch.

1. TRPA1 calcium fluorescence assay

The potency of compounds inhibiting TRPA1 mediated calcium flux was determined on a FLIPR T etra® instrument using the following recombinant cell lines:

• CHO K1 cells expressing human (h)TRPA1 and GCaMP6

• CHO K1 cells expressing rat (r)TRPA1 and GCaMP6 and

Cells expressing TRPA1 were cultured in DMEM medium (Gibco #41965-039), 10% FCS, 14.5 mM HEPES, 1 mM sodium pyruvate, 1x non-essential amino acids (Gibco #11140-035) without selection antibiotics and frozen in 90% culture medium/ 10% DMSO. For the assay, frozen cells were thawed, resuspended in fresh culture medium supplemented with 2 μg/ml poly-D-lysine (Sigma P6407) and seeded into black 384- well microtiter plates with clear bottom (Greiner #781092) at a density of 6000-8000 cells/well in 30 μI/well. The seeded plates were incubated overnight at 37°C, 5% CO2. Prior to the measurement, culture medium was removed and cells were incubated for 30 min at 37°C in 30 μI/well tyrode buffer (2mM CaCI2, 130 mM NaCI, 5 mM KCI, 20 mM HEPES, 1 mM MgCI2, 5 mM NaHCO3, pH 7.4, 0.01% BSA and 200 μg/ml brilliant black) supplemented with Fluo-8 AM calcium dye for cells without GCaMP6.

Half-log serial dilutions of the test compounds were prepared in DMSO starting at a concentration of 10 mM. Before the measurement, the compounds were further diluted 100-fold in tyrode buffer and added to the cells (10 μl/well) resulting in final concentrations between 25 μM and 0.8 nM. The plates were incubated with compounds for 10 min at room temperature.

Plates were placed in the FLIPR and fluorescence was measured for 3s as a baseline read. The agonist super cinnemaldehyde (Sigma S3322) was added at EC80 (typically 1 μM for hTRPA1, 3 μM for rTRPA1, 0.5 μM for mTRPA1, 10 μM for gpTRPA1) and the change of calcium fluorescence was measured for 2 min. Dose-response data were fitted using a four-parameter logistic function to calculate IC50 values with proprietary analysis software. Table 2 below collates the IC ₅₀ values thus obtained from the TRPA1 calcium fluorescence assay for human and rat channels for individual working examples of the invention (some as mean values from multiple independent individual determinations).

Table 2:

2. In vitro calcitonin gene-related peptide (CGRP) release assay in rat dorsal root ganglions (DRG) neurons

Method

DRG were isolated from ~ 6 week old female Sprague Dawiey rats and treated with 400 μI of 10 mM HEPES containing dipase 0.5 mg/ml, collagenase 2.5 mg/ml, and 6 mg/ml BSA. The ganglion were triturated, passed through a 50 pm filter and plated at a density of 5000 cells/well in a 96 well plates. DRG cells were cultured for 72 h prior to running the assay. DRG neurons were pretreated with the compound for 20 min prior to the addition of supercinnamaldehyde (SCMA, TRPA1-receptor agonist). After a further 20 min, the supernatant was collected and frozen at -20 °C until the CGRP content was measured using an enzyme immunometric assay (CGRP ELISA kit, Berlin bioreagents #A05482). The ELISA plates were prepared according to the manufacturer's instructions, 100 μI of the collected supernatant added and the plates incubated at 4 °C overnight. The plates were then washed, 200 mI of Ellman's reagent added and the absorbance measured at 414 nm using a Safire plate reader (Tecan), CGRP content was converted to pg/ml using a standard curve

Data

TRPA1 has been shown to be co-localized with CGRP in a subset of sensory neurons, and its activation leads to CGRP release from central and peripheral nerve endings. In our study, SCMA (3 μM) stimulated CGRP release from rat DRG neurons, and the effect was inhibited by preincubation with the compound (Table 3).

Table 3: Rat IC ₅₀ from in vitro rat CGRP release assay for example 16

3. Cinnamaldehyde-induced nocifensive behaviors in rats Method

Example 16 was tested in the model of intraplantar cinnamaldehyde (CA)-induced nocifensive pain behaviors in male Sprague Dawley rats. Briefly, 50 μI of CA at 5 mM was injected at the plantar surface of one hind paw. Immediately after injection, the number and the duration of nocifensive behaviors (including licking or flinching) were quantitated by a blinded experimenter during 5 minutes. Example 16 or vehicle (10% DMSO, 40% Solutol, 50% water for injection, vol/vol) were dosed via oral route (p.o.) 1 hour before CA injection. Data were expressed as the mean number of flinches, the mean duration of licking behaviors and the mean duration of nocifensive behaviors for each treatment group. Data were analysed by performing a one way ANOVA. Planned comparison of means (each versus vehicle) was performed by using a Dunnett's post hoc test, provided that a main effect was detected. For p values less than 0.05, the results were deemed to be statistically significant.

Data

Intraplantar injection of cinnamaldehyde (5 mM in 50 μI) in the rat resulted in robust flinching and licking responses. Oral administration of example 16 prevented CA-induced nocifensive behaviors in a dose-dependent manner, demonstrating an “on-target” effect (see Table 4).

Table 4: Rat CA in vivo model data for example 16 as test compound

Data were expressed as mean ± standard deviation (SD) for each treatment group * p<0.05, ** p<0.01 , *** p<0.001, **** p<0.0001, different from vehicle group (Dunnett's post-hoc test). p.o.: oral route

Table 5 summarizes the average plasma levels of example 16, approximately 1.25 hours after treatment.

Table 5: Average plasma levels of example 16 as test compound 75 minutes after treatment

4. CFA-induced mechanical hyperalgesia in rats Methods

Compound was tested in the model of intraplantar Complete Freund's Adjuvant (CFA)- induced acute (24 hours setting) inflammatory pain in male Sprague Dawley rats. Briefly, 25 μl of CFA at 1 mg/ml was injected into the plantar surface of one hind paw. Mechanical hyperalgesia was measured using the Pressure Application Measurement apparatus (Ugo Basile, Gemonio, Italy). A linearly increasing pressure was applied to an area of approximately 50 mm ² of the plantar side of the hind paw until a behavioural response (paw withdrawal) was observed or until the pressure reached 1000 grams of force (gf). The pressure at which the behavioural response occurred was recorded as the “Paw Withdrawal Threshold” (PWT). Both CFA-injected and contralateral PWTs were determined for each rat, in each treatment group and at each time point of the studies. The measurements were performed blinded. Mechanical hyperalgesia testing was performed before injecting CFA, 24 hours after CFA injection (pre-drug baseline), 2 and 4 hours after treatment. Compound or vehicle (10% DMSO, 40% Solutol, 50% water for injection, vol/vol) were dosed via oral route (p.o.) once 24 hours after CFA injection. Data were expressed as the mean PWT for each treatment group and at each time point. PWT data were analysed by performing a two way ANOVA with repeated measures (time x treatment). Planned comparison of means (each versus vehicle) was performed by using a Dunnett's post hoc test, provided that a main effect was detected. For p values less than 0.05, the results were deemed to be statistically significant.

Data with example 16:

Intraplantar CFA in the rat induced acute inflammatory pain characterized by a robust reduction of PWT 24 hours after injection. Oral administration of example 16, 24 hours after intraplantar CFA, prevented the development of inflammatory pain after the injection of CFA. After therapeutic treatment, significant reduction of inflammatory pain was observed 2 hours post-dose after 10 and 30 mg/kg, and 4 hours post-dose after 30 mg/kg (see Table 6). Table 6: Rat CFA in vivo model data for example 16 as test compound

Data were expressed as the mean PWT ± standard deviation (SD) for each treatment group and at each time point. **** p<0.0001, different from vehicle group at same time point (Dunnett's post-hoc test). Table 7: Average plasma levels of example 16 as test compound 4.5 hours after last treatment