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Chronic hepatitis B (CHB) is a major worldwide public health problem and novel anti-HBV therapies preventing liver disease progression to cirrhosis and hepatocellular carcinoma are urgently needed. Over the last several years, capsid assembly modulators (CAM) have emerged as clinically effective anti-HBV agents which can inhibit HBV replication in CHB patients. As part of a drug discovery program aimed at obtaining novel CAM endowed with high in vitro and in vivo antiviral activity, we identified a novel series of sulfamoylbenzamide (SBA) derivatives. Compound 10, one of the most in vitro potent SBA-derived CAM discovered to date, showed excellent pharmacokinetics in mice suitable for oral dosing. When studied in a transgenic mouse model of hepatic HBV replication, it was considerably more potent than NVR 3-778, the first sulfamoylbenzamide (SBA) CAM that entered clinical trials for CHB, at reducing viral replication in a dose-dependent fashion. We present herein the discovery process, the SAR analysis and the pre-clinical profile of this novel SBA CAM., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A new series of in vitro potent and highly selective histone methyl transferase enzyme G9a inhibitors was obtained. In particular, compound 2a, one the most potent G9a inhibitor identified, was endowed with >130-fold selectivity over GLP and excellent ligand efficiency. Therefore, it may represent a valuable tool compound to validate the role of highly selective G9a inhibitors in different pathological conditions. When 2a was characterized in vitro in cellular models of skeletal muscle differentiation, a relevant increase of myofibers' size and reduction of the fibroadipogenic infiltration were observed, further confirming the therapeutic potential of selective G9a inhibitors for the treatment of Duchenne muscle dystrophy., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The hypothalamic peptides orexin-A and orexin-B are potent agonists of two G-protein coupled receptors, namely the OX(1) and the OX(2) receptor. These receptors are widely distributed, though differentially, in the rat brain. In particular, the OX(1) receptor is highly expressed throughout the hypothalamus, whilst the OX(2) receptor is mainly located in the ventral posterior nucleus. A large body of compelling evidence, both pre-clinical and clinical, suggests that the orexin system is profoundly implicated in sleep disorders. In particular, modulation of the orexin receptors activation by appropriate antagonists was proven to be an efficacious strategy for the treatment of insomnia in man. A novel, drug-like bis-amido piperidine derivative was identified as potent dual OX(1) and OX(2) receptor antagonists, highly effective in a pre-clinical model of sleep., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Two complementary stereospecific synthetic approaches for the preparation of unsymmetrical ortho-substituted N-(4,4-diphenylbut-3-enyl) derivatives of nipecotic acid are described. Determination of the activity of the prepared compounds at the GAT-1 transporter highlighted differing SAR requirements of the E- and Z-phenyl rings, and led to the discovery of a compound with comparable potency to tiagabine. Some attempts to replace nipecotic acid with alternative novel amino acids are also described., (Copyright © 2010. Published by Elsevier Ltd.)

A new class of selective NPS antagonist was developed starting from a commercially available product identified by screening activities. Experimental NMR observations and computational experiments allowed the discovery of a new class of derivatives. 5-Phenyl-2-[2-(1-piperidinylcarbonyl)phenyl]-2,3-dihydro-1H-pyrrolo[1,2-c]imidazol-1-one represents a new lead compound in the NPS antagonist field., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Antagonists of the corticotropin-releasing factor (CRF) neuropeptide may prove effective in treating stress and anxiety related disorders. In an effort to identify antagonists with improved physico-chemical properties a new series of CRF(1) antagonists were designed to substitute the propyl groups at the C7 position of the pyrazolo[1,5-a]pyrimidine core of 1 with heterocycles. Compound (S)-8d was identified as a high affinity ligand with a pK(i) value of 8.2 and a functional CRF(1) antagonist with pIC(50) value of 7.0 in the in vitro CRF ACTH production assay., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A novel class of benzimidazole NPY Y5 receptor antagonists was prepared exploiting a privileged spirocarbamate moiety. The structure-activity relationship of this series and efforts to achieve a profile suitable for further development and an appropriate pharmacokinetic profile in rat are described. Optimisation led to the identification of the brain penetrant, orally bioavailable Y5 antagonist 9b which significantly inhibited the food intake induced by a Y5 selective agonist with a minimal effective dose of 30mg/kg po., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

5-{2-[4-(2-Methyl-5-quinolinyl)-1-piperazinyl]ethyl}-2(1H)-quinolinones and 3,4-dihydro-2(1H)-quinolinones have been identified with different combinations of 5-HT(1) autoreceptor antagonist and hSerT potencies and excellent rat PK profiles. The availability of tool compounds with a range of profiles at targets known to play a key role in the control of synaptic 5-HT levels will allow exploration of different pharmacological profiles in a range of animal behavioral and disease models., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A new class of selective orexin 2 antagonist was identified among commercial products. Initial SAR was obtained using commercial derivatives only prior to starting ad hoc medicinal chemistry activities., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A novel series of trans-8-aminomethyl-1-oxa-3-azaspiro[4.5]decan-2-one derivatives was identified with potent NPY Y5 antagonist activity. Optimization of the original lead furnished compounds 23p and 23u, which combine sub-nanomolar Y5 activity with metabolic stability, oral bioavailability, brain penetration and strong preclinical profile for development. Both compounds significantly inhibited the food intake induced by a Y5 selective agonist with minimal effective doses of 3mg/kg po., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A new class of azabicyclo[3.1.0]benzenesulfonamides is presented as selective dopamine D3 antagonists together with SAR and selectivity data., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

A novel imidazobenzazepine template (5a) with potent dual H(1)/5-HT(2A) antagonist activity was identified. Application of a zwitterionic approach to this poorly selective and poorly developable starting point successfully delivered a class of high quality leads, 3-[4-(3-R(1)-2-R-5H-imidazo[1,2-b][2]benzazepin-11-yl)-1-piperazinyl]-2,2-dimethylpropanoic acids (e.g., 9, 19, 20, and 21), characterized by potent and balanced H(1)/5-HT(2A) receptor antagonist activities and good developability profiles., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Novel series of pyrrole-pyrazinone and pyrazole-pyrazinone have been identified as potent and selective Vasopressin(1b) receptor antagonists. Exploration of the substitution pattern around the core of these templates allowed generation of compounds with high inhibitory potency at the Vasopressin(1b) receptor, including examples that showed good selectivity with respect to Vasopressin(1a), Vasopressin(2), and Oxytocin receptor subtypes., (Copyright 2010 Elsevier Ltd. All rights reserved.)

A novel class of small molecule NPY Y5 antagonists based around an azabicyclo[3.1.0]hexane scaffold was identified through modification of a screening hit. Structure-activity relationships and efforts undertaken to achieve a favourable pharmacokinetic profile in rat are described., (2010 Elsevier Ltd. All rights reserved.)

The identification of a highly selective D(2) partial agonist, D(3) antagonist tool molecule which demonstrates high levels of brain exposure and selectivity against an extensive range of dopamine, serotonin, adrenergic, histamine, and muscarinic receptors is described., (Copyright 2010 Elsevier Ltd. All rights reserved.)

A focused exploration targeting conformationally restricted analogues of Vestipitant, resulted in the discovery of novel, in vitro potent NK(1) antagonists. In particular, two of the compounds reported exhibited a good pharmacokinetic (PK) profile and produced anxiolytic-like effects in the gerbil foot tapping (GFT) in vivo model., (Copyright 2009 Elsevier Ltd. All rights reserved.)

The lead optimization process to identify new selective dopamine D(3) receptor antagonists is reported. DMPK parameters and binding data suggest that selective D(3) receptor antagonists as potential PET ligands might have been identified.

The synthesis and the structure activity of a new series of pyrrolo[1,2-a]pyrazine is reported. These molecules are potent and selective non-competitive mGluR5 antagonists and may shed new light on the pattern of substitution tolerated by this receptor.

The synthesis and the SAR of a new series of potent and selective dopamine D(3) receptor antagonists is reported. The new scaffolds of the [g]-fused and the hetero-fused tricyclic benzazepine are here reported together with their pharmacokinetic profile.

The synthesis and SAR of a new series of potent and selective dopamine D(3) receptor antagonists is reported. The introduction of a tricyclic [h]-fused benzazepine moiety on the recently disclosed scaffold of 1,2,4-triazol-3-yl-thiopropyl-tetrahydrobenzazepines is reported. A full rat pharmacokinetic characterization is also reported.

Corticotropin-releasing factor (CRF), a 41 amino acid peptide neurohormone synthesised by specific hypothalamic nuclei in the brain, is implicated in stress-related function. Antagonism of CRF(1) receptors is an attractive therapeutic approach for the treatment of depression and anxiety. Unsaturated tetrahydrotriazaacenaphthylenes of general structure 3 have been identified as potent and selective CRF(1) receptor antagonists with a suitable oral pharmacokinetic profile.

Exploiting the SAR of the known pyrrole derivatives, a new class of mGluR1 antagonists was designed by replacement of the pyrrole core with an indole scaffold and consequent cyclization of the C-2 position into a tricyclic beta-carboline template. The appropriate exploration of the position C-6 with a combination of H-bond acceptor groups coupled with bulky/lipophilic moieties led to the discovery of a new series of mGluR1 antagonists. These compounds exhibited a non-competitive behavior, excellent pharmacokinetic properties, and good in vivo activity in animal models of acute and chronic pain, after oral administration.

Chiral tetrahydroquinoline derivatives have been prepared by an asymmetric Mannich-type condensation reaction using commercially available vinyloxyethylsilane and a N-arylimino R-(+)-t-butyl lactate ester, in the presence of a catalytic amount of metal triflates as Lewis acids. This synthetic approach gave rise to the target aldehyde intermediate in moderate facial diastereoselectivity and in high chemical yield. This efficient route enabled to scale up the synthesis of an orally bioavailable glycine antagonist showing outstanding in vivo anti-hyperalgesic activity in different animal models of sustained inflammation and chronic neuropathic pain.

The synthesis of a series of carbazole derivatives and their SAR at the NPY Y1 receptor is described. Modulation of physicochemical properties by appropriate decoration led to the identification of a high-affinity NPY Y1 antagonist that shows high brain penetration and modest oral bioavailability.

Following the recent disclosure of 3-methyl pyrrole-2,4-dicarboxylic acid 2-propyl ester 4-(1,2,2-trimethyl-propyl) ester as a potent and selective mGluR1 non-competitive antagonist, the use of a doubly (13)C-labeled analogue to identify, and consequently prevent, metabolically labile positions is reported.

The SAR of a new series of tetrahydrocarbazole derivatives is described: the appropriate decoration of this template led to the identification of a new class of NPY-1 antagonists showing good in vitro potency and a promising in vivo pharmacokinetic profile in rat.

Exploiting the SAR of the known pyrrole derivatives, a new class of mGluR1 antagonists was developed through a cyclization of the C-2 position on the pyrrole N-1 nitrogen. The resulting pyrrolo[1,2-a]pyrazinones are potent and noncompetitive antagonists.

Two isomers of the hexahydro-tetraazaacenaphthylene templates (1 and 2) are presented as novel, potent, and selective corticotropin releasing factor-1 (CRF1) receptor antagonists. In this paper, we report the affinity and SAR of a series of compounds, as well as pharmacokinetic characterization of a chosen set. The anxiolitic activity of a selected example (2ba) in the rat pup vocalization model is also presented.

To identify neuroprotective agents after stroke, new substituted tetrahydroquinoline derivatives were designed as antagonists of the glycine binding site associated to the NMDA receptor, satisfying the key pharmacophoric requirements. In particular, the racemate 3c exhibited outstanding in vivo activity in the MCAo model in rats, when given iv both pre- and post-ischemia. Pure enantiomers 3c-(+) and 3c-(-) have been prepared following an original synthetic route. Despite the significant difference of activity observed in vitro, they shown similar neuroprotective profile in the MCAo model in rats.

Following the disclosure of 3,5-dimethyl pyrrole-2,4-dicarboxylic acid 2-propyl ester 4-(1,2,2-trimethyl-propyl) ester [3,5-dimethyl PPP] as a potent and selective mGluR1 non-competitive antagonist, we report here further in vivo characterization of this important tool and disclose the investigation of the C-5 position, which led to very potent compounds.

Compounds 2 and 3 were designed in order to probe the North-East region of the strichnine-insensitive glycine binding site of the NMDA receptor. The two products were obtained readily by a tandem aldol condensation-lactonization-elimination step which affords the desired E isomer with complete regioselection.