N-acyl-(3-substituted)-(8-methyl)-5,6-dihydro-[1,2,4]triazolo[4,3-a] pyrazines as selective NK-3 receptor antagonists, pharmaceutical composition, methods for use in NK-3 receptor-mediated disorders

1. A compound of Formula I:

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N, or X 1 is CH and X 2 is O;

represents a single or a double bond depending on X 1 and X 2 ; and

represents an (R)-enantiomer or a racemate of the compound of Formula I.

2. The compound according to claim 1 , having Formula I′ or Formula I″:

or a pharmaceutically acceptable solvate thereof, wherein

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N, or X 1 is CH and X 2 is O; and

represents a single or a double bond depending on X 1 and X 2 .

3. The compound according to claim 1 , having Formula Ia:

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl; and

represents an (R)-enantiomer or a racemate of the compound of Formula Ia.

4. The compound according to claim 1 , selected from Formula Ia′:

or a pharmaceutically acceptable solvate thereof, wherein

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl; and

R 4 is methyl or trifluoromethyl.

5. The compound according to claim 1 , having Formula Ib:

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl; and

represents an (R)-enantiomer or a racemate of the compound of Formula Ib.

6. The compound according to claim 1 , having Formula Ib′:

or a pharmaceutically acceptable solvate thereof, wherein

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl; and

R 4 is methyl or trifluoromethyl.

7. The compound according to claim 1 , selected from the group consisting of:

(R)-(4-fluorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo]4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-fluorophenyl) (8-methyl-3-(2-methylthiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-fluorophenyl) (8-methyl-3-(2-(trifluoromethyl)thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (2,3,4,5-tetrafluorophenyl)methanone;

(R)-(3,4-difluorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (2,3,4-trifluorophenyl)methanone;

(R)-(8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (3,4,5-trifluorophenyl)methanone;

(R)-(3-chloro-4-fluorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-chloro-3-fluorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-chlorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(3,4-dichlorophenyl) (8-methyl-3-(5-methylfuran-2-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(8-methyl-3-(2-(trifluoromethyl)thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (2,3,4,5-tetrafluorophenyl)methanone;

(R)-(3,4-difluorophenyl) (8-methyl-3-(2-(trifluoromethyl) thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(8-methyl-3-(2-(trifluoromethyl)thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (2,3,4-trifluorophenyl)methanone;

(R)-(8-methyl-3-(2-(trifluoromethyl)thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl) (3,4,5-trifluorophenyl)methanone;

(R)-(3-chloro-4-fluorophenyl) (8-methyl-3-(2-(trifluoromethyl) thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-chloro-3-fluorophenyl) (8-methyl-3-(2-(trifluoromethyl) thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

(R)-(4-chlorophenyl) (8-methyl-3-(2-(trifluoromethyl)thiazol-4-yl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanone;

and pharmaceutically acceptable solvates thereof.

8. A pharmaceutical composition or a medicament comprising a compound of Formula I

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N, or X 1 is CH and X 2 is O;

represents a single or a double bond depending on X 1 and X 2 ; and

represents an (R)-enantiomer or a racemate of the compound of Formula I, and

at least one pharmaceutically acceptable carrier, diluent, excipient and/or adjuvant.

9. A method for treating depression, anxiety, psychosis, schizophrenia, psychotic disorders, bipolar disorders, cognitive disorders, Parkinson's disease, Alzheimer's disease, attention deficit hyperactivity disorder (ADHD), pain, convulsion, obesity, inflammatory diseases selected from irritable bowel syndrome (IBS) and inflammatory bowel disorders, emesis, pre-eclampsia, airway related diseases selected from the group consisting of chronic obstructive pulmonary disease, asthma, airway hyperresponsiveness, bronchoconstriction and cough, urinary incontinence, contraception and sex hormone-dependent diseases selected from the group consisting of benign prostatic hyperplasia (BPH), prostatic hyperplasia, metastatic prostatic carcinoma, testicular cancer, breast cancer, ovarian cancer, androgen dependent acne, male pattern baldness, endometriosis, abnormal puberty, uterine fibrosis, uterine fibroid tumor, uterine leiomyoma, hormone-dependent cancers, hyperandrogenism, hirsutism, virilization, polycystic ovary syndrome (PCOS), premenstrual dysphoric disease (PMDD), HAIR-AN syndrome, ovarian hyperthecosis, other manifestations of high intraovarian androgen concentrations selected from follicular maturation arrest, atresia, anovulation, dysmenorrhea, dysfunctional uterine bleeding and infertility, androgen-producing tumor, menorrhagia and adenomyosis,

comprising the administration, to a patient in need thereof, of a pharmaceutically effective amount of a compound of Formula I

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N or X 1 is CH and X 2 is O;

represents a single or a double bond depending on X 1 and X 2 ; and

represents an (R)-enantiomer or a racemate of the compound of Formula I.

10. A method for treating hot flashes, comprising the administration, to a patient in need thereof, of a pharmaceutically effective amount of a compound of Formula I

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N, or X 1 is CH and X 2 is O;

represents a single or a double bond depending on X 1 and X 2 ; and

represents an (R)-enantiomer or a racemate of the compound of Formula I.

11. The method according to claim 9 , wherein the androgen-producing tumor is virilizing ovarian tumor or virilizing adrenal tumor.

12. A method for lowering the circulating luteinizing hormone (LH) levels, comprising administering to a patient in need thereof a pharmaceutically effective amount of a compound of Formula I,

or a pharmaceutically acceptable solvate thereof, wherein:

R 1 is H or F;

R 1′ is H;

R 2 is H, F or Cl;

R 2′ is H or F;

R 3 is F or Cl;

R 4 is methyl or trifluoromethyl;

X 1 is S and X 2 is N, or X 1 is CH and X 2 is O;

represents a single or a double bond depending on X1 and X2; and

represents an (R)-enantiomer or a racemate of the compound of Formula I.