Assessing NH300094, a novel dopamine and serotonin receptor modulator with cognitive enhancement property for treating schizophrenia.

Background: Schizophrenia is a serious psychiatric disorder that significantly affects the quality of life of patients. The objective of this study is to discover a novel antipsychotic candidate with highly antagonistic activity against both serotonin and dopamine receptors, demonstrating robust efficacy in animal models of positive, negative, and cognitive symptoms of schizophrenia. Methods: In the present study, we examined the activity of antipsychotic drug (NH300094) on 5-HT2A, 5-HT2C, 5-HT1A, 5-HT1B, 5-HT7, H1, M1, Alpha1A, D2L, D2S, Alpha2A, D3 receptor functional assay in vitro. In addition, multiple animal models, including dizocilpine (MK-801) induced hyper-locomotion; APO induced climbing; Conditioned Avoidance Response (CAR); DOI-Induced Head Twitch; Forced swimming test; Scopolamine induced cognitive impairment model, were used to verify the antipsychotic activity of NH300094 in preclinical. Results: In vitro functional assays have indicated that NH300094 is a potent antagonist of 5-HT receptors and dopamine receptors, with higher relative antagonistic activity against 5-HT2A receptor (5-HT2A IC50 = 0.47 nM) than dopamine receptors (D2L IC50 = 1.04 nM; D2S IC50 = 11.71 nM; D3 IC50 = 31.55 nM). Preclinical in vivo pharmacological study results showed that NH300094 was effective in multiple models, which is more extensive than the clinic drug Risperidone. Furthermore, the safety window for extrapyramidal side effects of NH300094 is significantly wider than that of Risperidone (For NH300094, mice catalepsy model ED50/ Mice MK-801 model ED50 = 104.6-fold; for Risperidone, mice catalepsy model ED50/ Mice MK-801 model ED50 = 12.9-fold), which suggests a potentially better clinical safety profile for NH300094. Conclusion: NH300094 is a novel potent serotonin and dopamine receptors modulator, which has good safety profile and therapeutic potential for the treatment of schizophrenia with cognition disorders.

Synthesis and Biological Evaluation of Fused Tricyclic Heterocycle Piperazine (Piperidine) Derivatives As Potential Multireceptor Atypical Antipsychotics.

Herein, a novel series of multireceptor ligands was developed as polypharmacological antipsychotic agents using the designed multiple ligand approach between dopamine receptors and serotonin receptors. Among them, compound 47 possessed unique pharmacological features, exhibiting high affinities for D2, D3, 5-HT1A, 5-HT2A, and 5-HT6 receptors and low efficacy at the off-target receptors (5-HT2C, histamine H1, and adrenergic α1 receptor). Compound 47 showed dose-dependent inhibition of apomorphine- and MK-801-induced motor behavior, and the conditioned avoidance response with low cataleptic effect. Moreover, compound 47 resulted nonsignificantly serum prolactin levels and weight gain change compared with risperidone. Additionally, compound 47 possessed a favorable pharmacokinetic profile with oral bioavailability of 58.8% in rats. Furthermore, compound 47 displayed procognition properties in a novel object recognition task in rats. Taken together, compound 47 may constitute a novel class of atypical antipsychotic drugs for schizophrenia.

Synthesis and biological evaluation of new 6-hydroxypyridazinone benzisoxazoles: Potential multi-receptor-targeting atypical antipsychotics.

In recent years, multi-targeting directed ligands have attracted great interest as possible new atypical antipsychotics. Combinations of dopamine and serotonin receptor ligands within single molecules might afford new therapeutic opportunities. Herein, we describe the synthesis of a novel series of 6-hydroxypyridazinone benzisoxazoles and their binding behaviors to different receptors in terms of atypical antipsychotic behaviors. The most potent compound (46) exhibited excellent affinities for certain receptors (D2, Ki = 0.5 ± 0.07 nM; 5-HT1A, Ki = 5.9 ± 0.8 nM; 5-HT2A, Ki = 0.3 ± 0.01 nM; 5-HT6, Ki = 0.5 ± 0.04 nM) and combined with low affinities for the H1, 5-HT2C, and adrenergic α1 receptors. In contrast to risperidone, compound 46 exhibited a high cataleptic threshold; this may be useful in the development of a novel class of drugs treating schizophrenia.

Synthesis and evaluation of new coumarin derivatives as potential atypical antipsychotics.

In this paper, we report the synthesis of novel, potential antipsychotic coumarin derivatives combining potent dopamine D2, D3 and serotonin 5-HT(1A), 5-HT(2A) receptors properties. We describe the structure activity relationship that leads us to the promising derivative: 7-(4-(4-(6-fluorobenzo[d]isoxazol-3-yl)piperidin-1-yl)butoxy)-6-methyl-2,3-dihydrocyclopenta[c]chromen-4(1H)-one 27. The unique pharmacological features of compound 27 are a high affinity for dopamine D2, D3 and serotonin 5-HT(1A), 5-HT(2A) receptors, together with a low affinity for H1 receptor (to reduce the risk of obesity under chronic treatment). In animal models, compound 27 inhibited apomorphine-induced climbing and MK-801-induced hyperactivity without observable catalepsy at the highest dose tested. In particular, compound 27 was more potent than clozapine.

Synthesis and biological investigation of coumarin piperazine (piperidine) derivatives as potential multireceptor atypical antipsychotics.

The discovery and synthesis of potential and novel antipsychotic coumarin derivatives, associated with potent dopamine D2, D3, and serotonin 5-HT1A and 5-HT2A receptor properties, are the focus of the present article. The most-promising derivative was 7-(4-(4-(6-fluorobenzo[d]isoxazol-3-yl)-piperidin-1-yl)butoxy)-4-methyl-8-chloro-2H-chromen-2-one (17m). This derivative possesses unique pharmacological features, including high affinity for dopamine D2 and D3 and serotonin 5-HT1A and 5-HT2A receptors. Moreover, it possesses low affinity for 5-HT2C and H1 receptors (to reduce the risk of obesity associated with chronic treatment) and hERG channels (to reduce the incidence of torsade des pointes). In animal models, compound 17m inhibited apomorphine-induced climbing behavior, MK-801-induced hyperactivity, and the conditioned avoidance response without observable catalepsy at the highest dose tested. Further, fewer preclinical adverse events were noted with 17m compared with risperidone in assays that measured prolactin secretion and weight gain. Acceptable pharmacokinetic properties were also noted with 17m. Taken together, 17m may constitute a novel class of drugs for the treatment of schizophrenia.

Synthesis and evaluation of a series of 2-substituted-5-thiopropylpiperazine (piperidine)-1,3,4-oxadiazoles derivatives as atypical antipsychotics.

BACKGROUND: It is important to develop novel antipsychotics that can effectively treat schizophrenia with minor side-effects. The aim of our work is to develop novel antipsychotics that act on dopamine D(2) and D(3), serotonin 5-HT(1A) and 5-HT(2A) receptors with low affinity for the serotonin 5-HT(2C) and H(1) receptors, which can effectively cure positive symptoms, negative symptoms and cognitive impairment without the weight gain side-effect. METHODOLOGY/PRINCIPAL FINDINGS: A series of 2-substituted-5-thiopropylpiperazine (piperidine) -1,3,4-oxadiazoles derivatives have been synthesized and the target compounds were evaluated for binding affinities to D(2), 5-HT(1A) and 5-HT(2A) receptors. Preliminary results indicated that compounds 14, 16 and 22 exhibited high affinities to D(2), 5-HT(1A) and 5-HT(2A) receptors among these compounds. Further binding tests showed that compound 22 had high affinity for D(3) receptor, and low affinity for serotonin 5-HT(2C) and H(1) receptors. In addition, compound 22 inhibited apomorphine-induced climbing behavior and MK-801-induced hyperactivity with no extrapyramidal symptoms liability in mice. Moreover, compound 22 exhibited acceptable pharmacokinetic properties. CONCLUSIONS/SIGNIFICANCE: Compound 22 showed an atypical antipsychotic activity without liability for extrapyramidal symptoms. We anticipate compound 22 to be useful for developing a novel class of drug for the treatment of schizophrenia.