Tryptophan hydroxylase (TPH1/TPH2)

As a follow-up to the discovery of our spirocyclic proline-based TPH1 inhibitor lead, we describe the optimization of this scaffold. Through a combination of X-ray co-crystal structure guided design and an in vivo screen, new substitutions in the lipophilic region of the inhibitors were identified[1].

Treatment with rodatristat (10–50 mg/kg; oral; mice) decreased intestinal 5-HT concentrations at 50 mg/kg and was much less effective at the lower dose of 10 mg/kg In particular, 15b (KAR5585), the prodrug of the potent TPH1 inhibitor 15a (KAR5417), showed robust reduction of intestinal serotonin (5-HT) levels in mice. Furthermore, oral administration of 15b generated high and sustained systemic exposure of the active parent 15a in rats and dogs. KAR5585 was selected for further pharmacological evaluation in disease models associated with a dysfunctional peripheral 5-HT system[1].

Animal/Disease Models: Mice[1]
Doses: 10 mg/kg and 50 mg/kg
Route of Administration: Oral
Experimental Results:Intestinal 5-HT concentration diminished at the 50 mg/kg dose, and its efficacy was significant at the 10 mg/kg dose decline.

[1]. Optimization of spirocyclic proline tryptophan hydroxylase-1 inhibitors. Bioorg Med Chem Lett. 2017 Feb 1;27(3):413-419.

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by chronically elevated pulmonary artery pressure, accompanied by extensive pulmonary vascular remodeling and perivascular inflammation, manifested by the aggregation of macrophages, lymphocytes, dendritic cells, and mast cells. Although the etiology of this disease remains unclear, clinical and preclinical data strongly suggest that serotonin (5-HT) plays an important role in this process. This study investigated the chronic effects of pharmacological inhibition of tryptophan hydroxylase 1 (TPH1), the rate-limiting enzyme in peripheral 5-HT biosynthesis, in two preclinical models of pulmonary arterial hypertension (PH)—monoclonalyl (MCT) rats and cesmasani (Suzhou Medino Pharmaceutical Co., Ltd.) hypoxic rat models. In two pulmonary hypertension models, ethyl(S)-8-(2-amino-6-((R)-1-(5-chloro-[1,1'-biphenyl]-2-yl)-2,2,2-trifluoroethoxy)pyrimidin-4-yl)-2,8-diazaspiro[4.5]decane-3-carboxylate and ethyl(S)-8-(2-amino-6-((R)-1-(3',4'-dimethyl-3-(3-methyl-1H-pyrazol-1-yl)-[1,1'-biphenyl]-4-yl)-2,2,2-trifluoroethoxy)pyrimidin-4-yl)-2,8-diazaspiro[4.5]decane-3-carboxylate, two novel orally active TPH1 inhibitors, exhibited nanomolar in vitro potency, reducing serum, intestinal, and pulmonary 5-HT levels in a dose-dependent manner and significantly decreasing pulmonary artery pressure. In male rats, pulmonary vascular wall thickening and obstruction were altered. In the MCT rat model, the decrease in pulmonary 5-HT levels was significantly associated with a reduction in histamine levels and mast cell number (P < 0.001, r² = 0.88). In contrast, the vasodilators ambrisentan and tadalafil, which are approved for the treatment of pulmonary arterial hypertension (PAH), did not reduce mast cell number or 5-HT levels and were less effective than TPH1 inhibitors in treating vascular remodeling. When used in combination with ambrisentan, TPH1 inhibitors showed an additive effect on pulmonary vascular remodeling and pressure. These data suggest that, in addition to reducing vascular remodeling, TPH1 inhibitors have the additional benefit of reducing perivascular mast cell aggregation associated with pulmonary arterial hypertension [2].

C27H27CLF3N5O3

561.983195543289

561.175

C, 57.71; H, 4.84; Cl, 6.31; F, 10.14; N, 12.46; O, 8.54

1673568-73-4

1673568-73-4;1673571-51-1 (ethyl);

117947705

Typically exists as White to off-white solids at room temperature

3.2

3

11

6

39

840

2

C1CN(CCC12C[C@H](NC2)C(=O)O)C3=CC(=NC(=N3)N)O[C@H](C4=C(C=C(C=C4)Cl)C5=CC=CC=C5)C(F)(F)F

ZNSPHKJFQDEABI-NZQKXSOJSA-N

InChI=1S/C27H27ClF3N5O3/c28-17-6-7-18(19(12-17)16-4-2-1-3-5-16)23(27(29,30)31)39-22-13-21(34-25(32)35-22)36-10-8-26(9-11-36)14-20(24(37)38)33-15-26/h1-7,12-13,20,23,33H,8-11,14-15H2,(H,37,38)(H2,32,34,35)/t20-,23+/m0/s1

2,8-Diazaspiro(4.5)decane-3-carboxylic acid, 8-(2-amino-6-((1R)-1-(5-chloro(1,1'-biphenyl)-2-yl)-2,2,2-trifluoroethoxy)-4-pyrimidinyl)-, (3S)-

KAR-5417; KAR 5417; KAR5417; KAR-5417; KAR5417; Rodatristat [USAN]; RVT-1201/014; 91D8378G2V; CHEMBL4104957; RVT-1201/014

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)