|
Dissociation constant of the compound; value ranges from 0.81-1.2 nM
|
None
|
0.81
nM
|
|
Journal : J. Med. Chem.
Title : N-fluoroalkylated and N-alkylated analogues of the dopaminergic D-2 receptor antagonist raclopride.
Year : 1990
Volume : 33
Issue : 9
First Page : 2430
Last Page : 2437
Authors : Lannoye GS, Moerlein SM, Parkinson D, Welch MJ.
Abstract : A series of raclopride [(S)-2-[(3,5-dichloro-6-methoxy-2- hydroxybenzamido)methyl]-1-ethylpyrrolidine] derivatives bearing pyrrolidino N-fluoroalkyl or -alkyl substituents were synthesized and evaluated as potential dopaminergic receptor-based positron tomography radiopharmaceuticals. Radiosynthetic procedures for producing the corresponding N-[18F]fluoroalkylated analogues of raclopride from 18F- (beta+, t1/2 = 110 min) in high specific activity were also developed. In vitro binding assays using competitive displacement of [3H]spiperone from primate caudate tissue indicated that the N-alkylated analogues of raclopride had Ki values of 5-40 nM, whereas the corresponding values for analogous N-fluoroalkylated derivatives ranged from 90-160 nM. The relatively low D-2 binding affinity of these fluorinated salicylamides was corroborated by in vivo tissue biodistribution results in rodents. On the basis of structure-binding correlations, the impact of intramolecular hydrogen bonding, ligand basicity, and steric bulk on the affinity of the benzamides for D-2 receptor binding are discussed. Strategies are presented for the development of alternative fluorinated salicylamides that are both receptor active and metabolically stable.
|
In vitro inhibition of [3H]spiperone binding to Dopamine receptor D2 in Macaca nemestrina striatal membranes
|
Macaca nemestrina
|
8.7
nM
|
|
Journal : J. Med. Chem.
Title : N-fluoroalkylated and N-alkylated analogues of the dopaminergic D-2 receptor antagonist raclopride.
Year : 1990
Volume : 33
Issue : 9
First Page : 2430
Last Page : 2437
Authors : Lannoye GS, Moerlein SM, Parkinson D, Welch MJ.
Abstract : A series of raclopride [(S)-2-[(3,5-dichloro-6-methoxy-2- hydroxybenzamido)methyl]-1-ethylpyrrolidine] derivatives bearing pyrrolidino N-fluoroalkyl or -alkyl substituents were synthesized and evaluated as potential dopaminergic receptor-based positron tomography radiopharmaceuticals. Radiosynthetic procedures for producing the corresponding N-[18F]fluoroalkylated analogues of raclopride from 18F- (beta+, t1/2 = 110 min) in high specific activity were also developed. In vitro binding assays using competitive displacement of [3H]spiperone from primate caudate tissue indicated that the N-alkylated analogues of raclopride had Ki values of 5-40 nM, whereas the corresponding values for analogous N-fluoroalkylated derivatives ranged from 90-160 nM. The relatively low D-2 binding affinity of these fluorinated salicylamides was corroborated by in vivo tissue biodistribution results in rodents. On the basis of structure-binding correlations, the impact of intramolecular hydrogen bonding, ligand basicity, and steric bulk on the affinity of the benzamides for D-2 receptor binding are discussed. Strategies are presented for the development of alternative fluorinated salicylamides that are both receptor active and metabolically stable.
|
In vitro inhibition of [3H]-Spiperone binding to Dopamine receptor D2 in Macaca nemestrina striatal membranes (using L-tartrate salt of authentic raclopride)
|
Macaca nemestrina
|
5.1
nM
|
|
Journal : J. Med. Chem.
Title : N-fluoroalkylated and N-alkylated analogues of the dopaminergic D-2 receptor antagonist raclopride.
Year : 1990
Volume : 33
Issue : 9
First Page : 2430
Last Page : 2437
Authors : Lannoye GS, Moerlein SM, Parkinson D, Welch MJ.
Abstract : A series of raclopride [(S)-2-[(3,5-dichloro-6-methoxy-2- hydroxybenzamido)methyl]-1-ethylpyrrolidine] derivatives bearing pyrrolidino N-fluoroalkyl or -alkyl substituents were synthesized and evaluated as potential dopaminergic receptor-based positron tomography radiopharmaceuticals. Radiosynthetic procedures for producing the corresponding N-[18F]fluoroalkylated analogues of raclopride from 18F- (beta+, t1/2 = 110 min) in high specific activity were also developed. In vitro binding assays using competitive displacement of [3H]spiperone from primate caudate tissue indicated that the N-alkylated analogues of raclopride had Ki values of 5-40 nM, whereas the corresponding values for analogous N-fluoroalkylated derivatives ranged from 90-160 nM. The relatively low D-2 binding affinity of these fluorinated salicylamides was corroborated by in vivo tissue biodistribution results in rodents. On the basis of structure-binding correlations, the impact of intramolecular hydrogen bonding, ligand basicity, and steric bulk on the affinity of the benzamides for D-2 receptor binding are discussed. Strategies are presented for the development of alternative fluorinated salicylamides that are both receptor active and metabolically stable.
|
Antidopamine activity in vitro by ability to displace [3H]spiperone from rat brain striatal preparations.
|
None
|
32.0
nM
|
|
Journal : J. Med. Chem.
Title : Potential neuroleptic agents. 4. Chemistry, behavioral pharmacology, and inhibition of [3H]spiperone binding of 3,5-disubstituted N-[(1-ethyl-2-pyrrolidinyl)methyl]-6-methoxysalicylamides.
Year : 1986
Volume : 29
Issue : 1
First Page : 61
Last Page : 69
Authors : de Paulis T, Kumar Y, Johansson L, Rämsby S, Hall H, Sällemark M, Angeby-Möller K, Ogren SO.
Abstract : A series of 3,5-disubstituted N-[(1-ethyl-2-pyrrolidinyl) methyl]-6-methoxysalicylamides was synthesized, starting from the 2,6-dimethoxybenzoic acids, by boron tribromide demethylation of the corresponding 3,5-disubstituted 2,6-dimethoxybenzamides and separation of the two positional isomers. The correct structure assignments were based on selective decoupling studies on their 13C NMR spectra. The salicylamide derivatives were tested for antidopamine activity in vivo by their ability to inhibit the apomorphine syndrome in the rat and in vitro by their ability to displace [3H]spiperone from striatal preparations of the rat brain. The activity seems to reside exclusively in the S enantiomer. Several compounds were considerably more potent than haloperidol, particularly those having an ethyl group in the 3-position and a halogen atom in the 5-position of the aromatic ring. The corresponding 5-alkyl-3-halogen-substituted compounds were much less active. A low acute toxicity was found for the most potent compounds. Some of the salicylamides displayed a 10-20-fold separation between the dose which blocks apomorphine-induced hyperactivity and that which blocks apomorphine-induced stereotypy. One compound, S-(-)-3,5-dichloro-N-[(1-ethyl-2-pyrrolidinyl) methyl]-6-methoxysalicylamide (raclopride, FLA 870) (13) had a stereotypy--hyperactivity separation more than twice that of sulpiride while being 100 times more potent in blocking the apomorphine effects. On this basis, 13 was selected for clinical trials against schizophrenia.
|
Affinity constant of compound was evaluated in human brain
|
Homo sapiens
|
7.1
nM
|
|
Journal : J. Med. Chem.
Title : Dopamine D-2 receptor imaging radiopharmaceuticals: synthesis, radiolabeling, and in vitro binding of (R)-(+)- and (S)-(-)-3-iodo-2-hydroxy-6-methoxy-N- [(1-ethyl-2-pyrrolidinyl)methyl]benzamide.
Year : 1988
Volume : 31
Issue : 5
First Page : 1039
Last Page : 1043
Authors : Kung HF, Kasliwal R, Pan SG, Kung MP, Mach RH, Guo YZ.
Abstract : In developing central nervous system (CNS) dopamine D-2 receptor imaging agents, enantiomers, R-(+) and S-(-) isomers, of 3-[125I]iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2- pyrrolidinyl)methyl]benzamide, [125I]IBZM, were synthesized, and their in vitro binding characteristics were evaluated in rat striatum tissue preparation. The (S)-(-)-[125I]IBZM showed high specific dopamine D-2 receptor binding (Kd = 0.43 nM, Bmax = 0.48 pmol/mg of protein). Competition data of various ligands for IBZM binding displayed the following rank order of potency: spiperone greater than (S)-(-)-IBZM greater than (+)-butaclamol much greater than (R)-(+)-IBZM greater than (S)-(-)-BZM greater than dopamine greater than ketanserin greater than SCH23390 much greater than propanolol. The results indicate that [125I]IBZM binds specifically to the dopamine D-2-receptor with stereospecificity. The [123I]IBZM is potentially useful as an imaging agent for the investigation of dopamine D-2 receptors in humans.
|
Inhibition of [3H]spiperone binding to rat striatal dopamine receptor D2 was determined in vitro
|
None
|
32.0
nM
|
|
Journal : J. Med. Chem.
Title : Potential antipsychotic agents. 9. Synthesis and stereoselective dopamine D-2 receptor blockade of a potent class of substituted (R)-N-[(1-benzyl-2-pyrrolidinyl)methyl]benzamides. Relations to other side chain congeners.
Year : 1991
Volume : 34
Issue : 3
First Page : 948
Last Page : 955
Authors : Högberg T, Ström P, de Paulis T, Stensland B, Csöregh I, Lundin K, Hall H, Ogren SO.
Abstract : A number of substituted N-[(1-benzyl-2-pyrrolidinyl)methyl]benzamides and -salicylamides have been prepared and investigated as dopamine D-2 receptor antagonists in vitro and in vivo. The affinity was found to be confined to the R enantiomer, in contrast to the corresponding N-ethyl or N-allyl derivatives. The X-ray structure of one of the compounds (15) confirmed the R stereochemistry. This compound (15) was found to adopt a solid-state conformation in which the 4-fluorobenzyl group is folded over the salicylamide moiety. Benzamides having a 2,3-dimethoxy substitution pattern (24 and 26) or salicylamides with a 5,6-dimethoxy grouping (21 and 22) were especially potent, in that they inhibited [3H]spiperone binding to rat striatal dopamine D-2 receptors in vitro with IC50 values of about 1 nM. The new compounds' ability to block apomorphine-induced stereotypies correlated with the affinity for the [3H]spiperone binding site. Higher dose levels were necessary to induce catalepsy than to block the apomorphine-induced responses. The influence of the aromatic substituents on the potency of substituted benzamides with three types of side chains, i.e. (R)-(1-benzyl-2-pyrrolidinyl)methyl, (S)-(1-ethyl-2-pyrrolidinyl)methyl and 1-benzyl-4-piperidinyl, was compared. The 3-bromo-5,6-dimethoxysalicylamide substitution pattern was found to be the most general since it gave very potent compounds in all series. The substituted (R)-N-[(1-(4-fluoro-benzyl)-2-pyrrolidinyl)methyl]benzamides (26) and -salicylamides (22) are suitable for development into 18F radioligands without altering the parent structure.
|
In vitro ability to inhibit the binding of [3H]spiperone to dopamine receptor D2 in rat striatal membranes.
|
None
|
32.0
nM
|
|
Journal : J. Med. Chem.
Title : Potential antipsychotic agents 5. Synthesis and antidopaminergic properties of substituted 5,6-dimethoxysalicylamides and related compounds.
Year : 1990
Volume : 33
Issue : 4
First Page : 1155
Last Page : 1163
Authors : Högberg T, Bengtsson S, de Paulis T, Johansson L, Ström P, Hall H, Ogren SO.
Abstract : A series of 3-substituted 5,6-dimethoxysalicylamides III (9-13 and 15) has been synthesized from the corresponding 2,5,6-trimethoxybenzoic acids. Relaxation times T1 and carbon chemical shifts of the methoxy groups in III showed that the 6-methoxy group adopts a nearly perpendicular orientation and the 5-methoxy group takes on a more coplanar orientation with respect to the ring plane in solution. The salicylamides III display a very high and stereoselective affinity for the [3H]spiperone and [3H]raclopride binding sites in vitro. Regioisomeric salicylamides IV also exhibit pronounced, but lower than III, affinity for the [3H]spiperone binding site. The structural requirements were further assessed by studies of the related amino analogues 23 and 24 and hydroxy analogue 27. The 3-bromo compound 11 (FLB 463) was studied in various in vivo models and compared with the dopamine-D2 antagonists sulpiride, raclopride, eticlopride, and haloperidol. The high potency of 11 to selectively block dopamine-D2 receptors in vitro and in vivo combined with indications on a low potential for motor side effects makes it a very interesting new member of the class of substituted salicylamides.
|
In vitro binding affinity for Dopamine D2 receptor of rat using [3H]YM-09151 as radioligand
|
None
|
3.4
nM
|
|
Journal : J. Med. Chem.
Title : Synthesis and pharmacological evaluation of 1-[(1,2-diphenyl-1H-4-imidazolyl)methyl]-4-phenylpiperazines with clozapine-like mixed activities at dopamine D(2), serotonin, and GABA(A) receptors.
Year : 2002
Volume : 45
Issue : 21
First Page : 4655
Last Page : 4668
Authors : Asproni B, Pau A, Bitti M, Melosu M, Cerri R, Dazzi L, Seu E, Maciocco E, Sanna E, Busonero F, Talani G, Pusceddu L, Altomare C, Trapani G, Biggio G.
Abstract : A series of 18 1-[(1,2-diphenyl-1H-4-imidazolyl)methyl]-4-piperazines (1a-r) were designed and synthesized as possible ligands with mixed dopamine (DA) D(2)/serotonin 5-HT(1A) affinity, with the aim of identifying novel compounds with neurochemical and pharmacological properties similar to those of clozapine. The binding profile at D(2) like, 5-HT(1A), and 5-HT(2A) receptors of title compounds was determined. Modifications made in the phenyl rings of the parent compound (1a) produced congeners endowed with a broad range of binding affinities for DA D(2) like, serotonin 5-HT(1A), and 5-HT(2A) receptors, with IC(50) values ranging from 25 to >10,000 nM. As for the modification of the piperazine N(4)-phenyl ring, the affinities for both D(2) like and 5-HT(1A) receptors were progressively increased by introduction of ortho-methoxy and ethoxy groups (1b,o, respectively). Data revealed the presence of a para-chloro substituent in 1g to be associated with a relatively high affinity and substantial selectivity for D(2) like receptors, whereas the meta-chloro analogue 1f exhibited preferential affinity for 5-HT(1A) receptors. A quantitative structure-affinity relationship analysis of the measured binding data resulted in regression equations that highlighted substituent physicochemical properties modulating the binding to subtypes 1A and 2A of serotonin 5-HT receptors but not to D(2) like receptors. Thus, besides an electron-withdrawing field effect and ortho substitution, which both influence binding to serotonin 5-HT receptor subtypes, though to a different extent as revealed by regression coefficients in the multiparametric regression equations, the affinity of congeners 1a-r to 5-HT(1A) receptors proved to be linearly correlated with volume/polarizability descriptors, whereas their affinity to 5-HT(2A) receptors correlated with lipophilicity constants through a parabolic relationship. 1-[(1,2-Diphenyl-1H-4-imidazolyl)methyl]-4-(2-methoxyphenyl)piperazine (1b), with a D(2)/5-HT(1A) IC(50) ratio of approximately 1, was selected for a further pharmacological study. In rats, the intraperitoneal administration of compound 1b, like that of clozapine, induced an increase in the extracellular concentration of DA measured in the medial prefrontal cortex. Furthermore, 1b and clozapine each inhibited GABA-evoked Cl(-) currents at recombinant GABA(A) receptors expressed in Xenopus oocytes. These findings suggest that compound 1b may represent an interesting prototype of a novel class of drugs endowed with a neurochemical profile similar to that of atypical antipsychotics.
|
In vivo inhibitory activity against dopamine (D2) receptor in rat caudate-putamen tissue
|
None
|
7.2
nM
|
|
Journal : Bioorg. Med. Chem. Lett.
Title : Synthesis and affinity of a possible byproduct of electrophilic radiolabeling of [123I]IBZM.
Year : 2003
Volume : 13
Issue : 22
First Page : 4015
Last Page : 4017
Authors : Baldwin RM, Fu X, Kula NS, Baldessarini RJ, Amici L, Innis RB, Tamagnan GD.
Abstract : The iodobenzamide neuroleptic analogue (S)-N-(1-ethylpyrrolidin-2-ylmethyl)-2-hydroxy-5-iodo-6-methoxybenzamide (5-IBZM) was synthesized stereospecifically and its pharmacological properties were compared with the 3-iodo isomer (IBZM) used for imaging D(2) receptors in vivo. The isomer 5-IBZM had 100-fold lower affinity than IBZM and migrated with similar retention time as the byproduct formed during electrophilic iodination of BZM.
|
Inhibition of 0.1 nM of [125I]- (S)-N-(1-Ethyl-pyrrolidin-2-ylmethyl)-5-iodo-2-methoxy-benzamide binding in striatal homogenates of rat brain
|
None
|
1.3
nM
|
|
Journal : J. Med. Chem.
Title : (S)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[125I]iodo- 2-methoxybenzamide hydrochloride, a new selective radioligand for dopamine D-2 receptors.
Year : 1988
Volume : 31
Issue : 10
First Page : 2027
Last Page : 2033
Authors : de Paulis T, Janowsky A, Kessler RM, Clanton JA, Smith HE.
Abstract : From salicyclic acid, the two enantiomers of N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-iodo-2-methoxybenzamide (6b) were prepared in a five-step synthesis. With use of Heindel's triazene method for introduction of the radionuclide, the iodine-125-labeled substituted benzamide was obtained with a calculated specific activity of 136 Ci/mmol and 14% radiochemical yield. For the preparation of the iodine-125-labeled benzamide with higher specific activity, this method was unsuccessful and utilization of the corresponding tri-n-butyltin derivative was required. Treatment of the latter in dilute hydrochloric acid with sodium iodide-125 and chloramine-T gave [125I](S)-6b in 56% radiochemical yield and at least 97% radiochemical purity. The displacement of [125I](S)-6b and [3H](S)-sulpiride from their respective binding sites in striatal rat brain homogenates using various neuroleptic agents showed that (S)-6b has the same binding profile but more potent binding for dopamine D-2 receptors than has sulpiride. These experiments also indicate that the S enantiomer of 6b is a specific ligand (KD = 1.2 nM) for the D-2 receptor. Further, the octanol-water partition coefficient of (S)-6b as determined by reverse-phase high-performance liquid chromatography was found to be 40 times greater than that for sulpiride. Thus (S)-6b has a lipophilicity that will allow a relatively higher uptake into the brain compared to sulpiride. In vivo experiments with rats show that [125I](S)-6b penetrates readily into the brain and is preferentially localized in the striatum as compared to the cerebellum, the ratio of uptake being 7.2 to 1, 60 min after injection. These observations of good brain penetration and high affinity and selectivity for D-2 receptors indicate that the corresponding iodine-123-labeled benzamide may be a useful ligand for the noninvasive visualization study of dopamine D-2 receptor sites in vivo by single photon emission computed tomography.
|
Inhibition of [3H](S)-sulpiride binding in striatal homogenates of rat brain
|
None
|
14.0
nM
|
|
Journal : J. Med. Chem.
Title : (S)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[125I]iodo- 2-methoxybenzamide hydrochloride, a new selective radioligand for dopamine D-2 receptors.
Year : 1988
Volume : 31
Issue : 10
First Page : 2027
Last Page : 2033
Authors : de Paulis T, Janowsky A, Kessler RM, Clanton JA, Smith HE.
Abstract : From salicyclic acid, the two enantiomers of N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-iodo-2-methoxybenzamide (6b) were prepared in a five-step synthesis. With use of Heindel's triazene method for introduction of the radionuclide, the iodine-125-labeled substituted benzamide was obtained with a calculated specific activity of 136 Ci/mmol and 14% radiochemical yield. For the preparation of the iodine-125-labeled benzamide with higher specific activity, this method was unsuccessful and utilization of the corresponding tri-n-butyltin derivative was required. Treatment of the latter in dilute hydrochloric acid with sodium iodide-125 and chloramine-T gave [125I](S)-6b in 56% radiochemical yield and at least 97% radiochemical purity. The displacement of [125I](S)-6b and [3H](S)-sulpiride from their respective binding sites in striatal rat brain homogenates using various neuroleptic agents showed that (S)-6b has the same binding profile but more potent binding for dopamine D-2 receptors than has sulpiride. These experiments also indicate that the S enantiomer of 6b is a specific ligand (KD = 1.2 nM) for the D-2 receptor. Further, the octanol-water partition coefficient of (S)-6b as determined by reverse-phase high-performance liquid chromatography was found to be 40 times greater than that for sulpiride. Thus (S)-6b has a lipophilicity that will allow a relatively higher uptake into the brain compared to sulpiride. In vivo experiments with rats show that [125I](S)-6b penetrates readily into the brain and is preferentially localized in the striatum as compared to the cerebellum, the ratio of uptake being 7.2 to 1, 60 min after injection. These observations of good brain penetration and high affinity and selectivity for D-2 receptors indicate that the corresponding iodine-123-labeled benzamide may be a useful ligand for the noninvasive visualization study of dopamine D-2 receptor sites in vivo by single photon emission computed tomography.
|
Inhibitory concentration required for displacing radioligand [3H]SPI from DA D-2 receptor
|
None
|
32.0
nM
|
|
Journal : J. Med. Chem.
Title : Conformational analysis of dopamine D-2 receptor antagonists of the benzamide series in relation to a recently proposed D-2 receptor-interaction model.
Year : 1992
Volume : 35
Issue : 13
First Page : 2355
Last Page : 2363
Authors : Pettersson I, Liljefors T.
Abstract : Conformational analysis using molecular mechanics calculations (MM2(87)) has been performed for four different types of benzamides which display high affinity for the dopamine D-2 receptor. In order to elucidate the conformation of the receptor-bound molecules, a previously described dopamine D-2 receptor-interaction model has been employed. We conclude that all four types of benzamides accommodated in the proposed receptor-interaction model are in low-energy conformations. An acyclic amide side chain is concluded to adopt an extended conformation in the receptor-bound benzamide. A phenylpyrrole analogue of the benzamides could similarly be fitted to the model. Using the receptor-interaction model, the enantioselectivity of benzamides with an N-ethyl-2-pyrrolidinylmethyl side chain could be rationalized in terms of different conformational energies of the receptor-bound enantiomers. Two different receptor sites for N-alkyl substituents are suggested.
|
The affinity for the Dopamine receptor D2 was assessed by the inhibition of [3H]-spiperone binding in rat striatal membranes in vitro.
|
None
|
32.0
nM
|
|
Journal : J. Med. Chem.
Title : Potential antipsychotic agents. 7. Synthesis and antidopaminergic properties of the atypical highly potent (S)-5-bromo-2,3-dimethoxy-N-[(1-ethyl-2-pyrrolidinyl)methyl]benzamide and related compounds. A comparative study.
Year : 1990
Volume : 33
Issue : 8
First Page : 2305
Last Page : 2309
Authors : Högberg T, de Paulis T, Johansson L, Kumar Y, Hall H, Ogren SO.
Abstract : (S)-5-Bromo-2,3-dimethoxy-N-[(1-ethyl-2-pyrrolidinyl)methyl]benzamide (6) and some related compounds, i.e. the R isomer 7, the 3-hydroxy analogue 8, the desbromo derivative 9, the monomethoxy compound 10, and the 2,4-dimethoxy analogue 11, have been synthesized from the corresponding benzoic acids. The benzamides, lacking o-hydroxy groups, were evaluated for their affinity for the [3H]spiperone binding site and for their inhibition of apomorphine-induced behavioral responses in relation to the effect of the corresponding salicylamides. Besides the 2-hydroxy-3-methoxybenzamide 12 and the related 1,4-benzodioxane (13) and 2,3-dihydrobenzofuran (14), carboxamides were investigated in order to evaluate the stereoelectronic requirements on the 2-methoxy group for the receptor interaction. The study supports the view that the o-methoxy group may adopt coplanar, as well as perpendicular orientations, and maintain the intramolecular hydrogen bonding required in the bioactive conformation. The benzamide 6 was found to be equipotent with the analogous highly active salicylamide 3 (FLB 463) both in vitro and in vivo. In addition, 6 displayed a preferential inhibition of the hyperactivity component of the behavioral syndrome, which is regarded to indicate a low tendency to induce extrapyramidal side effects in man at antipsychotically effective doses. The benzamide class of compounds (6-10) were found to be somewhat more sensitive to the structural modifications than the salicylamide class, i.e. the o-hydroxy-substituted benzamides (2-5). The potent and selective benzamide 6 (FLB 457) is highly suitable for investigations of dopamine D-2 mediated responses and, in radiolabeled form, for receptor binding studies in vitro and in vivo.
|
Affinity constant of compound was evaluated in rat striatum tissue preparation.
|
None
|
1.1
nM
|
|
Journal : J. Med. Chem.
Title : Dopamine D-2 receptor imaging radiopharmaceuticals: synthesis, radiolabeling, and in vitro binding of (R)-(+)- and (S)-(-)-3-iodo-2-hydroxy-6-methoxy-N- [(1-ethyl-2-pyrrolidinyl)methyl]benzamide.
Year : 1988
Volume : 31
Issue : 5
First Page : 1039
Last Page : 1043
Authors : Kung HF, Kasliwal R, Pan SG, Kung MP, Mach RH, Guo YZ.
Abstract : In developing central nervous system (CNS) dopamine D-2 receptor imaging agents, enantiomers, R-(+) and S-(-) isomers, of 3-[125I]iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2- pyrrolidinyl)methyl]benzamide, [125I]IBZM, were synthesized, and their in vitro binding characteristics were evaluated in rat striatum tissue preparation. The (S)-(-)-[125I]IBZM showed high specific dopamine D-2 receptor binding (Kd = 0.43 nM, Bmax = 0.48 pmol/mg of protein). Competition data of various ligands for IBZM binding displayed the following rank order of potency: spiperone greater than (S)-(-)-IBZM greater than (+)-butaclamol much greater than (R)-(+)-IBZM greater than (S)-(-)-BZM greater than dopamine greater than ketanserin greater than SCH23390 much greater than propanolol. The results indicate that [125I]IBZM binds specifically to the dopamine D-2-receptor with stereospecificity. The [123I]IBZM is potentially useful as an imaging agent for the investigation of dopamine D-2 receptors in humans.
|
Compound was measured for its ability to compete with [3H]spiperone binding to the human Dopamine receptor D3 transfected in CHO cells
|
None
|
3.7
nM
|
|
Journal : J. Med. Chem.
Title : Molecular modeling of the three-dimensional structure of dopamine 3 (D3) subtype receptor: discovery of novel and potent D3 ligands through a hybrid pharmacophore- and structure-based database searching approach.
Year : 2003
Volume : 46
Issue : 21
First Page : 4377
Last Page : 4392
Authors : Varady J, Wu X, Fang X, Min J, Hu Z, Levant B, Wang S.
Abstract : The dopamine 3 (D3) subtype receptor has been implicated in several neurological conditions, and potent and selective D3 ligands may have therapeutic potential for the treatment of drug addiction, Parkinson's disease, and schizophrenia. In this paper, we report computational homology modeling of the D3 receptor based upon the high-resolution X-ray structure of rhodopsin, extensive structural refinement in the presence of explicit lipid bilayer and water environment, and validation of the refined D3 structural models using experimental data. We further describe the development, validation, and application of a hybrid computational screening approach for the discovery of several classes of novel and potent D3 ligands. This computational approach employs stepwise pharmacophore and structure-based searching of a large three-dimensional chemical database for the identification of potential D3 ligands. The obtained hits are then subjected to structural novelty screening, and the most promising compounds are tested in a D3 binding assay. Using this approach we identified four compounds with K(i) values better than 100 nM and eight compounds with K(i) values better than 1 microM out of 20 compounds selected for testing in the D3 receptor binding assay. Our results suggest that the D3 structural models obtained from this study may be useful for the discovery and design of novel and potent D3 ligands. Furthermore, the employed hybrid approach may be more effective for lead discovery from a large chemical database than either pharmacophore-based or structure-based database screening alone.
|
Compound was evaluated for binding affinity towards DA D-2 receptor using radioligand [3H]SPI
|
None
|
9.5
nM
|
|
Journal : J. Med. Chem.
Title : Conformational analysis of dopamine D-2 receptor antagonists of the benzamide series in relation to a recently proposed D-2 receptor-interaction model.
Year : 1992
Volume : 35
Issue : 13
First Page : 2355
Last Page : 2363
Authors : Pettersson I, Liljefors T.
Abstract : Conformational analysis using molecular mechanics calculations (MM2(87)) has been performed for four different types of benzamides which display high affinity for the dopamine D-2 receptor. In order to elucidate the conformation of the receptor-bound molecules, a previously described dopamine D-2 receptor-interaction model has been employed. We conclude that all four types of benzamides accommodated in the proposed receptor-interaction model are in low-energy conformations. An acyclic amide side chain is concluded to adopt an extended conformation in the receptor-bound benzamide. A phenylpyrrole analogue of the benzamides could similarly be fitted to the model. Using the receptor-interaction model, the enantioselectivity of benzamides with an N-ethyl-2-pyrrolidinylmethyl side chain could be rationalized in terms of different conformational energies of the receptor-bound enantiomers. Two different receptor sites for N-alkyl substituents are suggested.
|
Displacement of [3H]- spiperone from dopamine receptor D2 of striatal membranes without sodium chloride
|
Rattus norvegicus
|
32.8
nM
|
|
Journal : J. Med. Chem.
Title : Synthesis and in vitro evaluation of 2,3-dimethoxy-5-(fluoroalkyl)-substituted benzamides: high-affinity ligands for CNS dopamine D2 receptors.
Year : 1991
Volume : 34
Issue : 5
First Page : 1612
Last Page : 1624
Authors : Bishop JE, Mathis CA, Gerdes JM, Whitney JM, Eaton AM, Mailman RB.
Abstract : A number of 2,3-dimethoxy-5-(fluoroalkyl)-N-[(1-ethyl-2- pyrrolidinyl)methyl]benzamides (with or without a 6-hydroxy group) were synthesized and evaluated as dopamine D2 receptor ligands. The parent acids were synthesized via the Claisen rearrangement of the appropriate O-allyl ethers, which were derived from o-vanillic acid or 2,3-dimethoxysalicylic acid. A decrease in reactivity was found to be characteristic of pentasubstituted benzoates, and difficulties were encountered with the introduction of fluorine onto the ethyl side chains. The (fluoroethyl)- and (fluoropropyl)salicylamides were 5 times more potent than the corresponding benzamides in inhibiting [3H]spiperone binding to the D2 receptor. These (fluoroalkyl)salicylamides are of potential value for in vivo positron emission tomography (PET) studies upon the basis of their relatively selective, high potency binding affinity for the D2 receptor.
|
Compound was evaluated for binding affinity towards dopamine receptor D2 in striatal membranes, using [3H]- spiperone as radioligand in the presence of sodium chloride
|
None
|
8.29
nM
|
|
Journal : J. Med. Chem.
Title : Synthesis and in vitro evaluation of 2,3-dimethoxy-5-(fluoroalkyl)-substituted benzamides: high-affinity ligands for CNS dopamine D2 receptors.
Year : 1991
Volume : 34
Issue : 5
First Page : 1612
Last Page : 1624
Authors : Bishop JE, Mathis CA, Gerdes JM, Whitney JM, Eaton AM, Mailman RB.
Abstract : A number of 2,3-dimethoxy-5-(fluoroalkyl)-N-[(1-ethyl-2- pyrrolidinyl)methyl]benzamides (with or without a 6-hydroxy group) were synthesized and evaluated as dopamine D2 receptor ligands. The parent acids were synthesized via the Claisen rearrangement of the appropriate O-allyl ethers, which were derived from o-vanillic acid or 2,3-dimethoxysalicylic acid. A decrease in reactivity was found to be characteristic of pentasubstituted benzoates, and difficulties were encountered with the introduction of fluorine onto the ethyl side chains. The (fluoroethyl)- and (fluoropropyl)salicylamides were 5 times more potent than the corresponding benzamides in inhibiting [3H]spiperone binding to the D2 receptor. These (fluoroalkyl)salicylamides are of potential value for in vivo positron emission tomography (PET) studies upon the basis of their relatively selective, high potency binding affinity for the D2 receptor.
|
Inhibition constant against dopamine receptor D2 in rat
|
Rattus norvegicus
|
1.1
nM
|
|
Journal : J. Med. Chem.
Title : Fluorinated and iodinated dopamine agents: D2 imaging agents for PET and SPECT.
Year : 1993
Volume : 36
Issue : 2
First Page : 221
Last Page : 228
Authors : Chumpradit S, Kung MP, Billings J, Mach R, Kung HF.
Abstract : A novel series of dual-labeling D2 dopamine agents (labeled with either 18F or 123I for PET or SPECT imaging, respectively) was investigated. Two desired fluorinated and iodinated dopamine agents, FIDA1, (S)-(-)-2-(2-fluoroethoxy)-5-iodo-3-methoxy-N-[(1-ethyl-2- pyrrolidinyl)methyl]-benzamide, and FIDA2, (R)-(+)-2,3-dimethoxy-5-iodo-N-[(1-(4'-fluorobenzyl)-2- pyrrolidinyl)-methyl]benzamide, were synthesized. Both compounds displayed high affinity to the D2 receptor of rat striatal membrane preparations (Kd = 0.13 and 0.02 nM for FIDA1 and FIDA2, respectively). The biodistribution study in rats exhibited high localization in the striata of the brain with the striatum/cerebellum ratio reaching 29.3 and 13.1 at 1 h post iv injection for FIDA1 and FIDA2, respectively. Imaging studies with [18F]- and [123I]FIDA2 in monkeys, with PET and SPECT, respectively, showed comparable high selective striatal uptake. These results suggest that they are potentially useful D2 dopamine receptor imaging agents for PET and SPECT.
|
Inhibition of [3H]spiperone binding to rat striatal membrane Dopamine receptor D2
|
Rattus norvegicus
|
1.3
nM
|
|
Journal : J. Med. Chem.
Title : Potential antipsychotic agents 5. Synthesis and antidopaminergic properties of substituted 5,6-dimethoxysalicylamides and related compounds.
Year : 1990
Volume : 33
Issue : 4
First Page : 1155
Last Page : 1163
Authors : Högberg T, Bengtsson S, de Paulis T, Johansson L, Ström P, Hall H, Ogren SO.
Abstract : A series of 3-substituted 5,6-dimethoxysalicylamides III (9-13 and 15) has been synthesized from the corresponding 2,5,6-trimethoxybenzoic acids. Relaxation times T1 and carbon chemical shifts of the methoxy groups in III showed that the 6-methoxy group adopts a nearly perpendicular orientation and the 5-methoxy group takes on a more coplanar orientation with respect to the ring plane in solution. The salicylamides III display a very high and stereoselective affinity for the [3H]spiperone and [3H]raclopride binding sites in vitro. Regioisomeric salicylamides IV also exhibit pronounced, but lower than III, affinity for the [3H]spiperone binding site. The structural requirements were further assessed by studies of the related amino analogues 23 and 24 and hydroxy analogue 27. The 3-bromo compound 11 (FLB 463) was studied in various in vivo models and compared with the dopamine-D2 antagonists sulpiride, raclopride, eticlopride, and haloperidol. The high potency of 11 to selectively block dopamine-D2 receptors in vitro and in vivo combined with indications on a low potential for motor side effects makes it a very interesting new member of the class of substituted salicylamides.
|
Tested for binding affinity against dopamine receptor D3 expressed in Sf9 cells.
|
None
|
9.25
nM
|
|
Journal : J. Med. Chem.
Title : Synthesis of (R,S)-2'-trans-7-hydroxy-2-[N-n-propyl-N-(3'-iodo-2'- propenyl)-amino]tetralin (trans-7-OH-PIPAT): a new D3 dopamine receptor ligand.
Year : 1993
Volume : 36
Issue : 10
First Page : 1499
Last Page : 1500
Authors : Foulon C, Kung MP, Kung HF.
|
In vitro binding affinity against dopamine receptor D2 in rat striata; value ranges from 1.8-3.0 nM
|
None
|
1.8
nM
|
|
Journal : J. Med. Chem.
Title : N-fluoroalkylated and N-alkylated analogues of the dopaminergic D-2 receptor antagonist raclopride.
Year : 1990
Volume : 33
Issue : 9
First Page : 2430
Last Page : 2437
Authors : Lannoye GS, Moerlein SM, Parkinson D, Welch MJ.
Abstract : A series of raclopride [(S)-2-[(3,5-dichloro-6-methoxy-2- hydroxybenzamido)methyl]-1-ethylpyrrolidine] derivatives bearing pyrrolidino N-fluoroalkyl or -alkyl substituents were synthesized and evaluated as potential dopaminergic receptor-based positron tomography radiopharmaceuticals. Radiosynthetic procedures for producing the corresponding N-[18F]fluoroalkylated analogues of raclopride from 18F- (beta+, t1/2 = 110 min) in high specific activity were also developed. In vitro binding assays using competitive displacement of [3H]spiperone from primate caudate tissue indicated that the N-alkylated analogues of raclopride had Ki values of 5-40 nM, whereas the corresponding values for analogous N-fluoroalkylated derivatives ranged from 90-160 nM. The relatively low D-2 binding affinity of these fluorinated salicylamides was corroborated by in vivo tissue biodistribution results in rodents. On the basis of structure-binding correlations, the impact of intramolecular hydrogen bonding, ligand basicity, and steric bulk on the affinity of the benzamides for D-2 receptor binding are discussed. Strategies are presented for the development of alternative fluorinated salicylamides that are both receptor active and metabolically stable.
|
Inhibition of [3H]raclopride binding to rat striatal dopamine receptor D2
|
Rattus norvegicus
|
1.3
nM
|
|
Journal : J. Med. Chem.
Title : Potential antipsychotic agents. 9. Synthesis and stereoselective dopamine D-2 receptor blockade of a potent class of substituted (R)-N-[(1-benzyl-2-pyrrolidinyl)methyl]benzamides. Relations to other side chain congeners.
Year : 1991
Volume : 34
Issue : 3
First Page : 948
Last Page : 955
Authors : Högberg T, Ström P, de Paulis T, Stensland B, Csöregh I, Lundin K, Hall H, Ogren SO.
Abstract : A number of substituted N-[(1-benzyl-2-pyrrolidinyl)methyl]benzamides and -salicylamides have been prepared and investigated as dopamine D-2 receptor antagonists in vitro and in vivo. The affinity was found to be confined to the R enantiomer, in contrast to the corresponding N-ethyl or N-allyl derivatives. The X-ray structure of one of the compounds (15) confirmed the R stereochemistry. This compound (15) was found to adopt a solid-state conformation in which the 4-fluorobenzyl group is folded over the salicylamide moiety. Benzamides having a 2,3-dimethoxy substitution pattern (24 and 26) or salicylamides with a 5,6-dimethoxy grouping (21 and 22) were especially potent, in that they inhibited [3H]spiperone binding to rat striatal dopamine D-2 receptors in vitro with IC50 values of about 1 nM. The new compounds' ability to block apomorphine-induced stereotypies correlated with the affinity for the [3H]spiperone binding site. Higher dose levels were necessary to induce catalepsy than to block the apomorphine-induced responses. The influence of the aromatic substituents on the potency of substituted benzamides with three types of side chains, i.e. (R)-(1-benzyl-2-pyrrolidinyl)methyl, (S)-(1-ethyl-2-pyrrolidinyl)methyl and 1-benzyl-4-piperidinyl, was compared. The 3-bromo-5,6-dimethoxysalicylamide substitution pattern was found to be the most general since it gave very potent compounds in all series. The substituted (R)-N-[(1-(4-fluoro-benzyl)-2-pyrrolidinyl)methyl]benzamides (26) and -salicylamides (22) are suitable for development into 18F radioligands without altering the parent structure.
|
Competitive binding assay against Dopamine receptor D2 in rat striatal membranes and [125I]-IBF radioligand
|
Rattus norvegicus
|
1.1
nM
|
|
Journal : J. Med. Chem.
Title : Synthesis and characterization of iodobenzamide analogues: potential D-2 dopamine receptor imaging agents.
Year : 1990
Volume : 33
Issue : 1
First Page : 171
Last Page : 178
Authors : Murphy RA, Kung HF, Kung MP, Billings J.
Abstract : (S)-N-[(1-Ethyl-2-pyrrolidinyl)methyl]-2-hydroxy-3-iodo-6- methoxybenzamide ([123I]IBZM) is a central nervous system (CNS) D-2 dopamine receptor imaging agent. In order to investigate the versatility of this parent structure in specific dopamine receptor localization and the potential for developing new dopamine receptor imaging agents, a series of new iodinated benzamides with fused ring systems, naphthalene (INAP) and benzofuran (IBF), was synthesized and radiolabeled, and the in vivo and in vitro biological properties were characterized. The best analogue of IBZM is IBF (21). The specific binding of [125I]IBF (21) with rat striatal tissue preparation was found to be saturable and displayed a Kd of 0.106 +/- 0.015 nM. Competition data of various receptor ligands for [125I]IBF (21) binding show the following rank order of potency: spiperone greater than IBF (21) greater than IBZM greater than (+)-butaclamol greater than (+/-)-ADTN,6,7 greater than ketanserin greater than SCH-23390 much greater than propranolol. The in vivo biodistribution results confirm that [125I]IBF (21) concentrated in the striatal area after iv injection into rats. The study demonstrates that [123I]IBF (21) is a potential agent for imaging CNS D-2 dopamine receptors.
|
Inhibition constant on radiolabeled [125I]FIDA1 binding to rat striatal membranes
|
Rattus norvegicus
|
2.31
nM
|
|
Journal : J. Med. Chem.
Title : Fluorinated and iodinated dopamine agents: D2 imaging agents for PET and SPECT.
Year : 1993
Volume : 36
Issue : 2
First Page : 221
Last Page : 228
Authors : Chumpradit S, Kung MP, Billings J, Mach R, Kung HF.
Abstract : A novel series of dual-labeling D2 dopamine agents (labeled with either 18F or 123I for PET or SPECT imaging, respectively) was investigated. Two desired fluorinated and iodinated dopamine agents, FIDA1, (S)-(-)-2-(2-fluoroethoxy)-5-iodo-3-methoxy-N-[(1-ethyl-2- pyrrolidinyl)methyl]-benzamide, and FIDA2, (R)-(+)-2,3-dimethoxy-5-iodo-N-[(1-(4'-fluorobenzyl)-2- pyrrolidinyl)-methyl]benzamide, were synthesized. Both compounds displayed high affinity to the D2 receptor of rat striatal membrane preparations (Kd = 0.13 and 0.02 nM for FIDA1 and FIDA2, respectively). The biodistribution study in rats exhibited high localization in the striata of the brain with the striatum/cerebellum ratio reaching 29.3 and 13.1 at 1 h post iv injection for FIDA1 and FIDA2, respectively. Imaging studies with [18F]- and [123I]FIDA2 in monkeys, with PET and SPECT, respectively, showed comparable high selective striatal uptake. These results suggest that they are potentially useful D2 dopamine receptor imaging agents for PET and SPECT.
|
Inhibition constant on radiolabeled [125I]FIDA2 binding to rat striatal membranes
|
Rattus norvegicus
|
5.0
nM
|
|
Journal : J. Med. Chem.
Title : Fluorinated and iodinated dopamine agents: D2 imaging agents for PET and SPECT.
Year : 1993
Volume : 36
Issue : 2
First Page : 221
Last Page : 228
Authors : Chumpradit S, Kung MP, Billings J, Mach R, Kung HF.
Abstract : A novel series of dual-labeling D2 dopamine agents (labeled with either 18F or 123I for PET or SPECT imaging, respectively) was investigated. Two desired fluorinated and iodinated dopamine agents, FIDA1, (S)-(-)-2-(2-fluoroethoxy)-5-iodo-3-methoxy-N-[(1-ethyl-2- pyrrolidinyl)methyl]-benzamide, and FIDA2, (R)-(+)-2,3-dimethoxy-5-iodo-N-[(1-(4'-fluorobenzyl)-2- pyrrolidinyl)-methyl]benzamide, were synthesized. Both compounds displayed high affinity to the D2 receptor of rat striatal membrane preparations (Kd = 0.13 and 0.02 nM for FIDA1 and FIDA2, respectively). The biodistribution study in rats exhibited high localization in the striata of the brain with the striatum/cerebellum ratio reaching 29.3 and 13.1 at 1 h post iv injection for FIDA1 and FIDA2, respectively. Imaging studies with [18F]- and [123I]FIDA2 in monkeys, with PET and SPECT, respectively, showed comparable high selective striatal uptake. These results suggest that they are potentially useful D2 dopamine receptor imaging agents for PET and SPECT.
|
Displacement of [3H]spiperone from dopamine D2short receptor in CHO cells
|
None
|
31.0
nM
|
|
Journal : Bioorg. Med. Chem.
Title : In vitro affinities of various halogenated benzamide derivatives as potential radioligands for non-invasive quantification of D(2)-like dopamine receptors.
Year : 2007
Volume : 15
Issue : 21
First Page : 6819
Last Page : 6829
Authors : Stark D, Piel M, Hübner H, Gmeiner P, Gründer G, Rösch F.
Abstract : Benzamide derivatives as radiotracers have played an important role in diagnosing malfunction in dopaminergic neurotransmission. A variety of halogenated and two unsubstituted benzamide derivatives were synthesised and their in vitro affinities to dopaminergic, serotonergic and adrenergic receptors and their lipophilicities were determined. As references IBZM (3), raclopride (4) and FLB457 (5) were tested as well. The two iodinated compounds NAE (27) and NADE (28) displayed K(i) values of 0.68 and 14 nM for the D(2) receptor. The well-established radiotracers FP (1) and DMFP (2) showed affinities in the same range as did the brominated compounds NABrE (29) and NABrDE (30). The log D(7.4) values of 2.91 for NAE (27) and of 2.81 for NADE (28) are in the range of those found for IBZM (3), FP (1) and DMFP (2). These facts allow to expect good properties for the two iodinated compounds NAE (27) and NADE (28) regarding in vivo imaging with SPECT.
|
Displacement of [3H]spiperone from dopamine D2long receptor in CHO cells
|
None
|
17.0
nM
|
|
Journal : Bioorg. Med. Chem.
Title : In vitro affinities of various halogenated benzamide derivatives as potential radioligands for non-invasive quantification of D(2)-like dopamine receptors.
Year : 2007
Volume : 15
Issue : 21
First Page : 6819
Last Page : 6829
Authors : Stark D, Piel M, Hübner H, Gmeiner P, Gründer G, Rösch F.
Abstract : Benzamide derivatives as radiotracers have played an important role in diagnosing malfunction in dopaminergic neurotransmission. A variety of halogenated and two unsubstituted benzamide derivatives were synthesised and their in vitro affinities to dopaminergic, serotonergic and adrenergic receptors and their lipophilicities were determined. As references IBZM (3), raclopride (4) and FLB457 (5) were tested as well. The two iodinated compounds NAE (27) and NADE (28) displayed K(i) values of 0.68 and 14 nM for the D(2) receptor. The well-established radiotracers FP (1) and DMFP (2) showed affinities in the same range as did the brominated compounds NABrE (29) and NABrDE (30). The log D(7.4) values of 2.91 for NAE (27) and of 2.81 for NADE (28) are in the range of those found for IBZM (3), FP (1) and DMFP (2). These facts allow to expect good properties for the two iodinated compounds NAE (27) and NADE (28) regarding in vivo imaging with SPECT.
|
Displacement of [3H]spiperone from dopamine D3 receptor in CHO cells
|
None
|
15.0
nM
|
|
Journal : Bioorg. Med. Chem.
Title : In vitro affinities of various halogenated benzamide derivatives as potential radioligands for non-invasive quantification of D(2)-like dopamine receptors.
Year : 2007
Volume : 15
Issue : 21
First Page : 6819
Last Page : 6829
Authors : Stark D, Piel M, Hübner H, Gmeiner P, Gründer G, Rösch F.
Abstract : Benzamide derivatives as radiotracers have played an important role in diagnosing malfunction in dopaminergic neurotransmission. A variety of halogenated and two unsubstituted benzamide derivatives were synthesised and their in vitro affinities to dopaminergic, serotonergic and adrenergic receptors and their lipophilicities were determined. As references IBZM (3), raclopride (4) and FLB457 (5) were tested as well. The two iodinated compounds NAE (27) and NADE (28) displayed K(i) values of 0.68 and 14 nM for the D(2) receptor. The well-established radiotracers FP (1) and DMFP (2) showed affinities in the same range as did the brominated compounds NABrE (29) and NABrDE (30). The log D(7.4) values of 2.91 for NAE (27) and of 2.81 for NADE (28) are in the range of those found for IBZM (3), FP (1) and DMFP (2). These facts allow to expect good properties for the two iodinated compounds NAE (27) and NADE (28) regarding in vivo imaging with SPECT.
|
Displacement of [3H]N-methylspiperone from human dopamine D3 receptor expressed in HEK293 cells after 1 hr by liquid scintillation counting analysis
|
Homo sapiens
|
13.4
nM
|
|
Journal : J. Med. Chem.
Title : Tranylcypromine substituted cis-hydroxycyclobutylnaphthamides as potent and selective dopamine D₃ receptor antagonists.
Year : 2014
Volume : 57
Issue : 11
First Page : 4962
Last Page : 4968
Authors : Chen J, Levant B, Jiang C, Keck TM, Newman AH, Wang S.
Abstract : We report a class of potent and selective dopamine D3 receptor antagonists based upon tranylcypromine. Although tranylcypromine has a low affinity for the rat D3 receptor (K(i) = 12.8 μM), our efforts have yielded (1R,2S)-11 (CJ-1882), which has K(i) values of 2.7 and 2.8 nM at the rat and human dopamine D3 receptors, respectively, and displays respective selectivities of >10000-fold and 223-fold over the rat and human D2 receptors. Evaluation in a β-arrestin functional assay showed that (1R,2S)-11 is a potent and competitive antagonist at the human D3 receptor.
|
Displacement of [3H]N-methylspiperone from human dopamine D2 receptor expressed in HEK293 cells after 1 hr by liquid scintillation counting analysis
|
Homo sapiens
|
12.7
nM
|
|
Journal : J. Med. Chem.
Title : Tranylcypromine substituted cis-hydroxycyclobutylnaphthamides as potent and selective dopamine D₃ receptor antagonists.
Year : 2014
Volume : 57
Issue : 11
First Page : 4962
Last Page : 4968
Authors : Chen J, Levant B, Jiang C, Keck TM, Newman AH, Wang S.
Abstract : We report a class of potent and selective dopamine D3 receptor antagonists based upon tranylcypromine. Although tranylcypromine has a low affinity for the rat D3 receptor (K(i) = 12.8 μM), our efforts have yielded (1R,2S)-11 (CJ-1882), which has K(i) values of 2.7 and 2.8 nM at the rat and human dopamine D3 receptors, respectively, and displays respective selectivities of >10000-fold and 223-fold over the rat and human D2 receptors. Evaluation in a β-arrestin functional assay showed that (1R,2S)-11 is a potent and competitive antagonist at the human D3 receptor.
|
Displacement of [3H]spiperone from human D2 receptor transfected in HEK cells
|
Homo sapiens
|
1.21
nM
|
|
Journal : J. Med. Chem.
Title : Shuttle-cargo fusion molecules of transport peptides and the hD2/3 receptor antagonist fallypride: a feasible approach to preserve ligand-receptor binding?
Year : 2014
Volume : 57
Issue : 10
First Page : 4368
Last Page : 4381
Authors : Wängler C, Chowdhury S, Höfner G, Djurova P, Purisima EO, Bartenstein P, Wängler B, Fricker G, Wanner KT, Schirrmacher R.
Abstract : To determine if the conjugation of a small receptor ligand to a peptidic carrier to potentially facilitate transport across the blood-brain barrier (BBB) by "molecular Trojan horse" transcytosis is feasible, we synthesized several transport peptide-fallypride fusion molecules as model systems and determined their binding affinities to the hD2 receptor. Although they were affected by conjugation, the binding affinities were found to be still in the nanomolar range (between 1.5 and 64.2 nM). In addition, homology modeling of the receptor and docking studies for the most potent compounds were performed, elucidating the binding modes of the fusion molecules and the structure elements contributing to the observed high receptor binding. Furthermore, no interaction between the hybrid compounds and P-gp, the main excretory transporter of the BBB, was found. From these results, it can be inferred that the approach to deliver small neuroreceptor ligands across the BBB by transport peptide carriers is feasible.
|
Displacement of [3H]raclopride from dopamine D2 receptor in Sprague-Dawley rat striatal membranes after 30 mins
|
Rattus norvegicus
|
2.6
nM
|
|
Journal : Eur. J. Med. Chem.
Title : Bifunctional compounds targeting both D2 and non-α7 nACh receptors: design, synthesis and pharmacological characterization.
Year : 2015
Volume : 101
First Page : 367
Last Page : 383
Authors : Matera C, Pucci L, Fiorentini C, Fucile S, Missale C, Grazioso G, Clementi F, Zoli M, De Amici M, Gotti C, Dallanoce C.
Abstract : We designed, prepared and tested a set of structural analogs 1-4 as new hybrid compounds by incorporating, through a common alkyl chain of variable length, the pharmacophoric elements of N-n-alkyl nicotinium salts (non-α7 nicotinic acetylcholine receptors antagonists) and of 7-hydroxy-2-(aminomethyl)chromanes (dopaminergic D2 receptor agonists). The target compounds, which were assayed in binding experiments and electrophysiological, functional and Erk1/2 activation tests, essentially combined the pharmacological profiles of their individual receptor ligands. Among the studied derivatives, hybrid 2, one of the shortest homologs, in addition to the antagonist nicotinic profile similar to the other three congeners, behaved as a high affinity ligand at the investigated heteromeric nAChRs and as a low efficacy agonist at D2Rs. These bifunctional derivatives represent novel pharmacological tools in the study of nicotine addiction.
|
Antibacterial activity against Staphylococcus aureus MRSA ATCC 43300 (CO-ADD:GP_020); MIC in CAMBH media, using NBS plates, by OD(600)
|
Staphylococcus aureus subsp. aureus
|
2.11
%
|
|
|
Antibacterial activity against Escherichia coli ATCC 25922 (CO-ADD:GN_001); MIC in CAMBH media using NBS plates, by OD(600)
|
Escherichia coli
|
10.63
%
|
|
|
Antibacterial activity against Klebsiella pneumoniae MDR ATCC 70063 (CO-ADD:GN_003); MIC in CAMBH media using NBS plates, by OD(600)
|
Klebsiella pneumoniae
|
6.89
%
|
|
|
Antibacterial activity against Pseudomonas aeruginosa ATCC 27853 (CO-ADD:GN_042); MIC in CAMBH media using NBS plates, by OD(600)
|
Pseudomonas aeruginosa
|
11.03
%
|
|
|
Antibacterial activity against Acinetobacter baumannii ATCC 19606 (CO-ADD:GN_034); MIC in CAMBH media using NBS plates, by OD600
|
Acinetobacter baumannii
|
10.65
%
|
|
|
Antifungal activity against Candida albicans ATCC 90028 (CO-ADD:FG_001); MIC in YNB media using NBS plates, by OD630
|
Candida albicans
|
2.44
%
|
|
|
Antifungal activity against Cryptococcus neoformans H99 ATCC 208821 (CO-ADD:FG_002); MIC in YNB media using NBS plates, by Resazurin OD(600-570)
|
Cryptococcus neoformans
|
1.03
%
|
|
|
Antiviral activity determined as inhibition of SARS-CoV-2 induced cytotoxicity of Caco-2 cells at 10 uM after 48 hours by high content imaging
|
Homo sapiens
|
17.88
%
|
|
Title : Identification of inhibitors of SARS-CoV-2 in-vitro cellular toxicity in human (Caco-2) cells using a large scale drug repurposing collection
Year : 2020
Authors : Bernhard Ellinger, Denisa Bojkova, Andrea Zaliani, Jindrich Cinatl, Carsten Claussen, Sandra Westhaus, Jeanette Reinshagen, Maria Kuzikov, Markus Wolf, Gerd Geisslinger, Philip Gribbon, Sandra Ciesek
Abstract : To identify possible candidates for progression towards clinical studies against SARS-CoV-2, we screened a well-defined collection of 5632 compounds including 3488 compounds which have undergone clinical investigations (marketed drugs, phases 1 -3, and withdrawn) across 600 indications. Compounds were screened for their inhibition of viral induced cytotoxicity using the human epithelial colorectal adenocarcinoma cell line Caco-2 and a SARS-CoV-2 isolate. The primary screen of 5632 compounds gave 271 hits. A total of 64 compounds with IC50 <20 µM were identified, including 19 compounds with IC50 < 1 µM. Of this confirmed hit population, 90% have not yet been previously reported as active against SARS-CoV-2 in-vitro cell assays. Some 37 of the actives are launched drugs, 19 are in phases 1-3 and 10 pre-clinical. Several inhibitors were associated with modulation of host pathways including kinase signaling P53 activation, ubiquitin pathways and PDE activity modulation, with long chain acyl transferases were effective viral inhibitors.
|
Antagonist activity at C-terminal RLuc8-fused D2 long receptor (unknown origin) transfected in human HEK293T cells co-expressing N-terminal Venus-tagged beta-arrestin2 assessed as increase in beta-arrestin2 recruitment measured after 5 mins in presence of coelenterazine H by BRET assay
|
Homo sapiens
|
1.82
nM
|
|
Antagonist activity at C-terminal RLuc8-fused D2 long receptor (unknown origin) transfected in human HEK293T cells co-expressing N-terminal Venus-tagged beta-arrestin2 assessed as increase in beta-arrestin2 recruitment measured after 5 mins in presence of coelenterazine H by BRET assay
|
Homo sapiens
|
1.83
nM
|
|
Journal : ACS Med Chem Lett
Title : Structure-Functional-Selectivity Relationship Studies of Novel Apomorphine Analogs to Develop D1R/D2R Biased Ligands.
Year : 2020
Volume : 11
Issue : 3
First Page : 385
Last Page : 392
Authors : Park H, Urs AN, Zimmerman J, Liu C, Wang Q, Urs NM.
Abstract : Loss of dopamine neurons is central to the manifestation of Parkinson's disease motor symptoms. The dopamine precursor L-DOPA, the most commonly used therapeutic agent for Parkinson's disease, can restore normal movement yet cause side-effects such as dyskinesias upon prolonged administration. Dopamine D1 and D2 receptors activate G-protein- and arrestin-dependent signaling pathways that regulate various dopamine-dependent functions including locomotion. Studies have shown that shifting the balance of dopamine receptor signaling toward the arrestin pathway can be beneficial for inducing normal movement, while reducing dyskinesias. However, simultaneous activation of both D1 and D2Rs is required for robust locomotor activity. Thus, it is desirable to develop ligands targeting both D1 and D2Rs and their functional selectivity. Here, we report structure-functional-selectivity relationship (SFSR) studies of novel apomorphine analogs to identify structural motifs responsible for biased activity at both D1 and D2Rs.
|
Antagonist activity at C-terminal RLuc8-fused D2 long receptor (unknown origin) transfected in human HEK293T cells co-expressing N-terminal Venus-tagged beta-arrestin2 assessed as increase in beta-arrestin2 recruitment measured after 5 mins in presence of coelenterazine H by BRET assay relative to control
|
Homo sapiens
|
95.0
%
|
|
Journal : ACS Med Chem Lett
Title : Structure-Functional-Selectivity Relationship Studies of Novel Apomorphine Analogs to Develop D1R/D2R Biased Ligands.
Year : 2020
Volume : 11
Issue : 3
First Page : 385
Last Page : 392
Authors : Park H, Urs AN, Zimmerman J, Liu C, Wang Q, Urs NM.
Abstract : Loss of dopamine neurons is central to the manifestation of Parkinson's disease motor symptoms. The dopamine precursor L-DOPA, the most commonly used therapeutic agent for Parkinson's disease, can restore normal movement yet cause side-effects such as dyskinesias upon prolonged administration. Dopamine D1 and D2 receptors activate G-protein- and arrestin-dependent signaling pathways that regulate various dopamine-dependent functions including locomotion. Studies have shown that shifting the balance of dopamine receptor signaling toward the arrestin pathway can be beneficial for inducing normal movement, while reducing dyskinesias. However, simultaneous activation of both D1 and D2Rs is required for robust locomotor activity. Thus, it is desirable to develop ligands targeting both D1 and D2Rs and their functional selectivity. Here, we report structure-functional-selectivity relationship (SFSR) studies of novel apomorphine analogs to identify structural motifs responsible for biased activity at both D1 and D2Rs.
|
Antagonist activity at D2 long receptor (unknown origin) transfected in human HEK293T cells assessed as increase in cAMP accumulation incubated for 2 hrs by cAMP Glo-sensor assay
|
Homo sapiens
|
100.0
nM
|
|
Antagonist activity at D2 long receptor (unknown origin) transfected in human HEK293T cells assessed as increase in cAMP accumulation incubated for 2 hrs by cAMP Glo-sensor assay
|
Homo sapiens
|
104.2
nM
|
|
Journal : ACS Med Chem Lett
Title : Structure-Functional-Selectivity Relationship Studies of Novel Apomorphine Analogs to Develop D1R/D2R Biased Ligands.
Year : 2020
Volume : 11
Issue : 3
First Page : 385
Last Page : 392
Authors : Park H, Urs AN, Zimmerman J, Liu C, Wang Q, Urs NM.
Abstract : Loss of dopamine neurons is central to the manifestation of Parkinson's disease motor symptoms. The dopamine precursor L-DOPA, the most commonly used therapeutic agent for Parkinson's disease, can restore normal movement yet cause side-effects such as dyskinesias upon prolonged administration. Dopamine D1 and D2 receptors activate G-protein- and arrestin-dependent signaling pathways that regulate various dopamine-dependent functions including locomotion. Studies have shown that shifting the balance of dopamine receptor signaling toward the arrestin pathway can be beneficial for inducing normal movement, while reducing dyskinesias. However, simultaneous activation of both D1 and D2Rs is required for robust locomotor activity. Thus, it is desirable to develop ligands targeting both D1 and D2Rs and their functional selectivity. Here, we report structure-functional-selectivity relationship (SFSR) studies of novel apomorphine analogs to identify structural motifs responsible for biased activity at both D1 and D2Rs.
|
Antagonist activity at D2 long receptor (unknown origin) transfected in human HEK293T cells assessed as increase in cAMP accumulation incubated for 2 hrs by cAMP Glo-sensor assay relative to control
|
Homo sapiens
|
89.28
%
|
|
Journal : ACS Med Chem Lett
Title : Structure-Functional-Selectivity Relationship Studies of Novel Apomorphine Analogs to Develop D1R/D2R Biased Ligands.
Year : 2020
Volume : 11
Issue : 3
First Page : 385
Last Page : 392
Authors : Park H, Urs AN, Zimmerman J, Liu C, Wang Q, Urs NM.
Abstract : Loss of dopamine neurons is central to the manifestation of Parkinson's disease motor symptoms. The dopamine precursor L-DOPA, the most commonly used therapeutic agent for Parkinson's disease, can restore normal movement yet cause side-effects such as dyskinesias upon prolonged administration. Dopamine D1 and D2 receptors activate G-protein- and arrestin-dependent signaling pathways that regulate various dopamine-dependent functions including locomotion. Studies have shown that shifting the balance of dopamine receptor signaling toward the arrestin pathway can be beneficial for inducing normal movement, while reducing dyskinesias. However, simultaneous activation of both D1 and D2Rs is required for robust locomotor activity. Thus, it is desirable to develop ligands targeting both D1 and D2Rs and their functional selectivity. Here, we report structure-functional-selectivity relationship (SFSR) studies of novel apomorphine analogs to identify structural motifs responsible for biased activity at both D1 and D2Rs.
|
Binding affinity to dopamine D3 receptor (unknown origin)
|
Homo sapiens
|
13.4
nM
|
|
Journal : J Med Chem
Title : Highly Selective Dopamine D3 Receptor (D3R) Antagonists and Partial Agonists Based on Eticlopride and the D3R Crystal Structure: New Leads for Opioid Dependence Treatment.
Year : 2016
Volume : 59
Issue : 16
First Page : 7634
Last Page : 7650
Authors : Kumar V, Bonifazi A, Ellenberger MP, Keck TM, Pommier E, Rais R, Slusher BS, Gardner E, You ZB, Xi ZX, Newman AH.
Abstract : The recent and precipitous increase in opioid analgesic abuse and overdose has inspired investigation of the dopamine D3 receptor (D3R) as a target for therapeutic intervention. Metabolic instability or predicted toxicity has precluded successful translation of previously reported D3R-selective antagonists to clinical use for cocaine abuse. Herein, we report a series of novel and D3R crystal structure-guided 4-phenylpiperazines with exceptionally high D3R affinities and/or selectivities with varying efficacies. Lead compound 19 was selected based on its in vitro profile: D3R Ki = 6.84 nM, 1700-fold D3R versus D2R binding selectivity, and its metabolic stability in mouse microsomes. Compound 19 inhibited oxycodone-induced hyperlocomotion in mice and reduced oxycodone-induced locomotor sensitization. In addition, pretreatment with 19 also dose-dependently inhibited the acquisition of oxycodone-induced conditioned place preference (CPP) in rats. These findings support the D3R as a target for opioid dependence treatment and compound 19 as a new lead molecule for development.
|
Binding affinity to dopamine D2 receptor (unknown origin)
|
Homo sapiens
|
12.7
nM
|
|
Journal : J Med Chem
Title : Highly Selective Dopamine D3 Receptor (D3R) Antagonists and Partial Agonists Based on Eticlopride and the D3R Crystal Structure: New Leads for Opioid Dependence Treatment.
Year : 2016
Volume : 59
Issue : 16
First Page : 7634
Last Page : 7650
Authors : Kumar V, Bonifazi A, Ellenberger MP, Keck TM, Pommier E, Rais R, Slusher BS, Gardner E, You ZB, Xi ZX, Newman AH.
Abstract : The recent and precipitous increase in opioid analgesic abuse and overdose has inspired investigation of the dopamine D3 receptor (D3R) as a target for therapeutic intervention. Metabolic instability or predicted toxicity has precluded successful translation of previously reported D3R-selective antagonists to clinical use for cocaine abuse. Herein, we report a series of novel and D3R crystal structure-guided 4-phenylpiperazines with exceptionally high D3R affinities and/or selectivities with varying efficacies. Lead compound 19 was selected based on its in vitro profile: D3R Ki = 6.84 nM, 1700-fold D3R versus D2R binding selectivity, and its metabolic stability in mouse microsomes. Compound 19 inhibited oxycodone-induced hyperlocomotion in mice and reduced oxycodone-induced locomotor sensitization. In addition, pretreatment with 19 also dose-dependently inhibited the acquisition of oxycodone-induced conditioned place preference (CPP) in rats. These findings support the D3R as a target for opioid dependence treatment and compound 19 as a new lead molecule for development.
|
SARS-CoV-2 3CL-Pro protease inhibition percentage at 20µM by FRET kind of response from peptide substrate
|
Severe acute respiratory syndrome coronavirus 2
|
16.39
%
|
|
Title : Identification of inhibitors of SARS-Cov2 M-Pro enzymatic activity using a small molecule repurposing screen
Year : 2020
Authors : Maria Kuzikov, Elisa Costanzi, Jeanette Reinshagen, Francesca Esposito, Laura Vangeel, Markus Wolf, Bernhard Ellinger, Carsten Claussen, Gerd Geisslinger, Angela Corona, Daniela Iaconis, Carmine Talarico, Candida Manelfi, Rolando Cannalire, Giulia Rossetti, Jonas Gossen, Simone Albani, Francesco Musiani, Katja Herzog, Yang Ye, Barbara Giabbai, Nicola Demitri, Dirk Jochmans, Steven De Jonghe, Jasper Rymenants, Vincenzo Summa, Enzo Tramontano, Andrea R. Beccari, Pieter Leyssen, Paola Storici, Johan Neyts, Philip Gribbon, and Andrea Zaliani
Abstract : Compound repurposing is an important strategy being pursued in the identification of effective treatment against the SARS-CoV-2 infection and COVID-19 disease. In this regard, SARS-CoV-2 main protease (M-Pro), also termed 3CL-Pro, is an attractive drug target as it plays a central role in viral replication by processing the viral polyprotein into 11 non-structural proteins. We report the results of a screening campaign involving ca 8.7 K compounds containing marketed drugs, clinical and preclinical candidates, and chemicals regarded as safe in humans. We confirmed previously reported inhibitors of 3CL-Pro, but we have also identified 68 compounds with IC50 lower than 1 uM and 127 compounds with IC50 lower than 5 uM. Profiling showed 67% of confirmed hits were selective (> 5 fold) against other Cys- and Ser- proteases (Chymotrypsin and Cathepsin-L) and MERS 3CL-Pro. Selected compounds were also analysed in their binding characteristics.
|
Antiviral activity determined as inhibition of SARS-CoV-2 induced cytotoxicity of VERO-6 cells at 10 uM after 48 hours exposure to 0.01 MOI SARS CoV-2 virus by high content imaging
|
Chlorocebus sabaeus
|
0.18
%
|
|
Antiviral activity determined as inhibition of SARS-CoV-2 induced cytotoxicity of VERO-6 cells at 10 uM after 48 hours exposure to 0.01 MOI SARS CoV-2 virus by high content imaging
|
Chlorocebus sabaeus
|
0.18
%
|
|
Title : Cytopathic SARS-Cov2 screening on VERO-E6 cells in a large repurposing effort
Year : 2020
Authors : Andrea Zaliani, Laura Vangeel, Jeanette Reinshagen, Daniela Iaconis, Maria Kuzikov, Oliver Keminer, Markus Wolf, Bernhard Ellinger, Francesca Esposito, Angela Corona, Enzo Tramontano, Candida Manelfi, Katja Herzog, Dirk Jochmans, Steven De Jonghe, Winston Chiu, Thibault Francken, Joost Schepers, Caroline Collard, Kayvan Abbasi, Carsten Claussen , Vincenzo Summa, Andrea R. Beccari, Johan Neyts, Philip Gribbon and Pieter Leyssen
Abstract : Worldwide, there are intensive efforts to identify repurposed drugs as potential therapies against SARS-CoV-2 infection and the associated COVID-19 disease. To date, the anti-inflammatory drug dexamethasone and (to a lesser extent) the RNA-polymerase inhibitor remdesivir have been shown to be effective in reducing mortality and patient time to recovery, respectively, in patients. Here, we report the results of a phenotypic screening campaign within an EU-funded project (H2020-EXSCALATE4COV) aimed at extending the repertoire of anti-COVID therapeutics through repurposing of available compounds and highlighting compounds with new mechanisms of action against viral infection. We screened 8702 molecules from different repurposing libraries, to reveal 110 compounds with an anti-cytopathic IC50 < 20 µM. From this group, 18 with a safety index greater than 2 are also marketed drugs, making them suitable for further study as potential therapies against COVID-19. Our result supports the idea that a systematic approach to repurposing is a valid strategy to accelerate the necessary drug discovery process.
