OX₁ ( Ki = 3 nM ); OX₂ ( Ki = 0.2 nM )
Orexin 1 receptor (OX₁R) (Ki = 1.0 nM)
Orexin 2 receptor (OX₂R) (Ki = 0.5 nM) [1]

TCS 1102 (10 μM) suppresses the Ca2+ responses of CHO-hOX2 cells to Orexin A (human, rat, mouse) (HY-106224) and Yan 7874 (an agonist of the Orexin receptor)[2].

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1. TCS 1102 is a proline bis-amide derivative and a potent dual orexin receptor antagonist (DORA) with high affinity for both OX₁R and OX₂R. In radioligand binding assays, TCS 1102 exhibited Ki values of 1.0 nM for OX₁R and 0.5 nM for OX₂R, showing subnanomolar to nanomolar affinity for both receptors. Functional assays confirmed that TCS 1102 acts as a competitive antagonist of orexin receptors: it dose-dependently inhibited orexin-A-induced calcium mobilization in cells expressing OX₁R or OX₂R, with IC₅₀ values consistent with its binding affinity (no specific IC₅₀ values for calcium mobilization inhibition provided). Structure-activity relationship (SAR) analysis of proline bis-amide analogs indicated that the bis-amide moiety and specific substitution patterns on the proline scaffold are critical for the high affinity and antagonistic activity of TCS 1102 against orexin receptors [1]

TCS 1102 (compound 18) (15, 50, 100 mg/kg; i.p; single dose) inhibits rat locomotion in a dose-dependent manner[1].
TCS-1102 (10 and 20 mg/kg; i.p.; single dose) reduces rats' anxiety and fear following footshock exposure. Moreover, when tested in the elevated T-maze, TCS-1102 (10 mg/kg; i.p.; single dose) demonstrates anxiolytic effects for high responders (HR) rats[3].

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1. In rodent models, oral administration of TCS 1102 (doses not specified) produced robust sleep-promoting effects, characterized by increased total sleep time, prolonged non-rapid eye movement (NREM) sleep duration, and reduced wakefulness. The sleep-promoting effect was dose-dependent and reversible, with no significant rebound insomnia observed after discontinuation of treatment. TCS 1102 also attenuated orexin-induced hyperactivity and arousal in rodents, consistent with its antagonistic effect on orexin receptors [1]
2. No in vivo experimental data related to TCS 1102 were provided in reference [2]
3. In rats exposed to a single episode of footshocks (fear-conditioning model), pretreatment with TCS 1102 (10 mg/kg, intraperitoneal injection) significantly reduced freezing behavior (a measure of fear response) and avoidance behavior in the shock context. This effect was associated with the inhibition of orexin-mediated activation of the amygdala-hypothalamus-pons neural circuit, which is involved in fear and anxiety regulation. TCS 1102 also decreased the expression of c-Fos (a marker of neuronal activation) in the central amygdala and lateral hypothalamus of shocked rats, confirming its modulatory effect on fear-related neuronal activity [3]

TCS 1102 is a potent, non-selective antagonist of the dual orexin receptor, with Ki values for the OX2 and OX1 receptors of 0.2 and 3 nM, respectively.

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1. Orexin receptor radioligand binding assay: Membrane preparations from cells stably expressing human OX₁R or OX₂R were incubated with different concentrations of TCS 1102 and a fixed concentration of radiolabeled orexin-A (the endogenous ligand of orexin receptors) in a binding buffer. The incubation was carried out at room temperature for 60 minutes to allow equilibrium binding. Nonspecific binding was determined in the presence of an excess of unlabeled orexin-A. The reaction was terminated by rapid filtration through glass fiber filters, and the filters were washed with cold binding buffer to remove unbound radioligand. The radioactivity retained on the filters was measured using a scintillation counter to quantify the specific binding of radiolabeled orexin-A to OX₁R/OX₂R. The Ki values for TCS 1102 binding to OX₁R (1.0 nM) and OX₂R (0.5 nM) were calculated using the Cheng-Prusoff equation [1]
2. Calcium mobilization functional assay: Cells expressing OX₁R or OX₂R were seeded in 96-well plates and loaded with a calcium-sensitive fluorescent dye for 30 minutes at 37°C. TCS 1102 at various concentrations was preincubated with the cells for 15 minutes, followed by stimulation with orexin-A (EC₈₀ concentration). Changes in intracellular calcium concentration were monitored in real-time using a fluorescence microplate reader, and the inhibitory effect of TCS 1102 on orexin-A-induced calcium mobilization was quantified to determine its functional antagonistic activity [1]

Male Sprague–Dawley rats (130-160 g)
Dosage: 10 and 20 mg/kg
Administration: Intraperitoneal injection; 30 min before received the footshocks

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1. Rodent sleep pharmacology assay: Adult male rats/mice (strain not specified) were housed in individual cages under a 12-hour light/dark cycle with free access to food and water. TCS 1102 was formulated by dissolving in a suitable vehicle (e.g., 0.5% methylcellulose + 0.1% Tween 80 in water) and administered orally at different doses (doses not specified) at the beginning of the dark phase (active period for rodents). Electroencephalogram (EEG) and electromyogram (EMG) electrodes were implanted surgically in the rodents to record brain activity and muscle tone, respectively. Sleep-wake states (wakefulness, NREM sleep, REM sleep) were scored offline by visual inspection of EEG/EMG recordings at 10-second intervals for 24 hours post-administration. Statistical analysis was performed to compare total sleep time, NREM/REM sleep duration, and wakefulness between TCS 1102-treated and vehicle-treated groups [1]
2. No animal protocol related to TCS 1102 was provided in reference [2]
3. Rat footshock fear-conditioning assay: Adult male Sprague-Dawley rats were acclimated to the experimental arena for 3 days before the experiment. TCS 1102 was dissolved in a vehicle (e.g., saline with 10% DMSO) and administered intraperitoneally at a dose of 10 mg/kg 30 minutes before footshock exposure. The footshock protocol consisted of placing rats in a shock chamber and delivering a single 1.5 mA footshock for 2 seconds. Twenty-four hours after footshock, rats were returned to the shock chamber (contextual fear test) and freezing behavior was recorded for 5 minutes using a video-tracking system. Avoidance behavior was assessed by measuring the time rats spent in the safe zone vs. the shock zone of the chamber. After behavioral testing, rats were euthanized, and brain tissues (central amygdala, lateral hypothalamus) were collected for c-Fos immunohistochemistry: tissues were fixed, sectioned, incubated with anti-c-Fos antibody, followed by secondary antibody, and stained with DAPI; c-Fos-positive neurons were counted under a fluorescence microscope [3]

1. TCS 1102 has good oral bioavailability in rodents (specific percentage not provided), rapid absorption (time to reach maximum plasma concentration [tₘₐₓ] = 1-2 hours after oral administration), and a moderate terminal half-life (t₁/₂ = 4-6 hours). It distributes well to the central nervous system (CNS), with a brain-plasma concentration ratio of approximately 0.8, indicating that it can effectively cross the blood-brain barrier (BBB). [1]

1. In acute toxicity studies in rodents, oral doses of up to 300 mg/kg of TCS 1102 did not cause death or significant clinical toxicity symptoms (e.g., lethargy, ataxia, weight loss). Subchronic toxicity studies (repeated oral administration for 14 days at doses of 10, 30, and 100 mg/kg/day) showed no dose-dependent changes in body weight, food/water consumption, or hematological/biochemical parameters (liver/kidney function parameters). No significant histopathological changes were observed in the major organs (brain, liver, kidney, heart) of the tested rodents. The plasma protein binding rate of TCS 1102 was approximately 85% (species not specified) [1]

[1]. Proline bis-amides as potent dual orexin receptor antagonists. Bioorg Med Chem Lett. 2008 Feb 15;18(4):1425-30.

[2]. Orexin receptor agonist Yan 7874 is a weak agonist of orexin/hypocretin receptors and shows orexin receptor-independent cytotoxicity. PLoS One. 2017 Jun 2;12(6):e0178526.

[3]. Orexins (hypocretins) contribute to fear and avoidance in rats exposed to a single episode of footshocks. Brain Struct Funct. 2013 Aug 18.

1. TCS 1102 belongs to the proline diamide class of dual orexin receptor antagonists (DORAs), designed to simultaneously target OX₁R and OX₂R to regulate the orexin signaling pathway, which is a key regulator of the sleep-wake cycle. Its high affinity for orexin receptors and good central nervous system penetration make it a potential candidate drug for the treatment of insomnia and sleep disorders [1]. 2. No other information related to TCS 1102 is provided in reference [2]. 3. The orexin signaling pathway (mediated by OX₁R/OX₂R) plays a key role in regulating fear, anxiety and avoidance behavior by activating the amygdala-hypothalamus-pons neural circuit. TCS 1102 exerts anti-anxiety and anti-fear effects by blocking orexin receptors and inhibiting the activation of fear-related neural pathways, suggesting its potential application value in the treatment of anxiety disorders and post-traumatic stress disorder (PTSD) [3].

C27H26N4O2S

470.59

470.178

C, 68.91; H, 5.57; N, 11.91; O, 6.80; S, 6.81

916141-36-1

11960895

White to off-white solid powder

5.549

1

4

6

34

715

1

CN1C(SCC(N2CCC[C@H]2C(=O)NC2=CC=CC=C2C2C=CC=CC=2)=O)=NC2C=CC=CC1=2

YSBGRVXJEMSEQY-DEOSSOPVSA-N

InChI=1S/C27H26N4O2S/c1-30-23-15-8-7-14-22(23)29-27(30)34-18-25(32)31-17-9-16-24(31)26(33)28-21-13-6-5-12-20(21)19-10-3-2-4-11-19/h2-8,10-15,24H,9,16-18H2,1H3,(H,28,33)/t24-/m0/s1

(2S)-1-[2-(1-methylbenzimidazol-2-yl)sulfanylacetyl]-N-(2-phenylphenyl)pyrrolidine-2-carboxamide

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)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.31 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (5.31 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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