93601-93-5Relevant academic research and scientific papers
Discovery of 4-(4-(2-((5-Hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)(propyl) amino)ethyl)piperazin-1-yl)quinolin-8-ol and its analogues as highly potent dopamine D2/D3 agonists and as iron chelator: In vivo activity indicates potential application in symptomatic and neuroprotective therapy for Parkinson's disease
Ghoshs, Balaram,Antonio, Tamara,Reith, Maarten E. A.,Dutta, Aloke K.
experimental part, p. 2114 - 2125 (2010/08/20)
The role of iron in the pathogenesis of Parkinson's disease (PD) has been implicated strongly because of generation of oxidative stress leading to dopamine cell death. In our overall goal to develop bifunctional/multifunctional drugs, we designed dopamine D2/D3 agonist molecules with a capacity to bind to iron. Binding assays were carried out with HEK-293 cells expressing either D2 or D3 receptor with tritiated spiperone to evaluate inhibition constants (K i). Functional activity of selected compounds was carried out with GTPyS binding assay. SAR results identified compounds (+)-19a and (-)-19b as two potent agonists for both D2 and D3 receptors (EC50 (GTPyS); D2 = 4.51 and 1.69 nM and D3 = 1.58 and 0.74 nM for (-)-19b and (+)-19a, respectively). In vitro complexation studies with 19b demonstrated efficient chelation with iron. Furthermore, the deoxyribose assay with 19b demonstrated potent antioxidant activity. In PD animal model study, (-)-19b exhibited potent in vivo activity in reversing locomotor activity in reserpinized rats and also in producing potent rotational activity in 6-OHDA lesioned rats. This reports initial development of unique lead molecules that might find potential use in symptomatic and neuroprotective treatment of PD.
Further delineation of hydrophobic binding sites in dopamine D 2/D3 receptors for N-4 substituents on the piperazine ring of the hybrid template 5/7-{[2-(4-aryl-piperazin-1-yl)-ethyl]-propyl-amino}-5, 6,7,8-tetrahydro-naphthalen-2-ol
Ghosh, Balaram,Antonio, Tamara,Gopishetty, Bhaskar,Reith, Maarten,Dutta, Aloke
experimental part, p. 5661 - 5674 (2010/10/01)
Here we report a structure-activity relationship (SAR) study of analogues of 5/7-{[2-(4-aryl-piperazin-1-yl)-ethyl]-propyl-amino}-5,6,7,8-tetrahydro- naphthalen-2-ol. Our SAR is focused on introduction of various substitutions in the piperazine ring of the hybrid template. The goal behind this study is to delineate the nature of the binding pocket for N-aryl substitution in the piperazine ring by observing the effect of various hydrophobic and other heteroaromatic substitutions on binding affinity (Ki), as measured with tritiated spiperone and HEK-293 cells expressing either D2 or D3 receptors. Functional activity of selected compounds was assessed with the GTPγS binding assay. Compound 8d was the most selective for the D3 receptor in the spiperone binding assay. An interesting similarity in binding affinity was observed between isoquinoline derivative D-301 and the 2-substituted pyridine derivative 8d, suggesting the importance of relative spatial relationships between the N-atom of the ligand and the molecular determinants of the binding pocket in D2/D3 receptors. Functional activity assays demonstrated high potency and selectivity of (+)-8a and (-)-28b (D2/D3 (ratio of EC50): 105 and 202, respectively) for the D3 receptor and both compounds were more selective compared to the reference drug ropinirole (D2/D3 (ratio of EC50): 29.5).
Investigation of various N-heterocyclic substituted piperazine versions of 5/7-{[2-(4-aryl-piperazin-1-yl)-ethyl]-propyl-amino}-5,6,7,8-tetrahydro-naphthalen-2-ol: Effect on affinity and selectivity for dopamine D3 receptor
Brown, Dennis A.,Mishra, Manoj,Zhang, Suhong,Biswas, Swati,Parrington, Ingrid,Antonio, Tamara,Reith, Maarten E.A.,Dutta, Aloke K.
experimental part, p. 3923 - 3933 (2009/10/10)
Here we report on the design and synthesis of several heterocyclic analogues belonging to the 5/7-{[2-(4-aryl-piperazin-1-yl)-ethyl]-propyl-amino}-5,6,7,8-tetrahydro-naphthalen-2-ol series of molecules. Compounds were subjected to [3H]spiperone binding assays, carried out with HEK-293 cells expressing either D2 or D3 dopamine receptors, in order to evaluate their inhibition constant (Ki) at these receptors. Results indicate that N-substitution on the piperazine ring can accommodate various substituted indole rings. The results also show that in order to maintain high affinity and selectivity for the D3 receptor the heterocyclic ring does not need to be connected directly to the piperazine ring as the majority of compounds included here are linked either via an amide or a methylene linker to the heterocyclic moiety. The enantiomers of the most potent racemic compound 10e exhibited differential activity with (-)-10e (Ki; D2 = 47.5 nM, D3 = 0.57 nM) displaying higher affinity at both D2 and D3 receptors compared to its enantiomer (+)-10e (Ki; D2 = 113 nM, D3 = 3.73 nM). Additionally, compound (-)-10e was more potent and selective for the D3 receptor compared to either 7-OH-DPAT or 5-OH-DPAT. Among the bioisosteric derivatives, the indazole derivative 10g and benzo[b]thiophene derivative 10i exhibited the highest affinity for D2 and D3 receptors. In the functional GTPγS binding study, one of the lead molecules, (-)-15, exhibited potent agonist activity at both D2 and D3 receptors with preferential affinity at D3.
4-PIPERIDINYL ALKYL AMINE DERIVATIVES AS MUSCARINIC RECEPTOR ANTAGONISTS
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, (2008/06/13)
This invention relates to compounds which are generally muscarinic receptor antagonists and which are represented by Formula I: wherein p, R1, R2, R3 and A are as defined in the specification, or individual isomers, racemi
