PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Piperazines”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1992

[Studies on zwitter-ionization of drugs. I. Synthesis and pharmacological activities of N-alkylcarboxylic acid derivatives of 4-(2-chlorodibenz-[b,f][1,4]oxazepin-11-yl)piperazine, 4-(2-chlorodibenzo[b, f]-[1,4]thiazepin-11-yl)piperazine, and 4-(11H-dibenz-[b,e]azepin-6-yl)piperazine].

The piperazine N-alkylcarboxylic acids of 2-chlorodibenz[b,f][1,4] oxazepine (3a), 2-chlorodibenzo[b,f] [1,4] thiazepine (3b), and dipenz[b,e] azepine (3c) from the corresponding piperazines (1a-c, R1 = H) were synthesized via the piperazine N-alkylcarboxylates (2a-c). The pharmacological activities of the piperazine N-alkylcarboxylic acids (3a-c) were evaluated. Compared with the parent compounds (1a-c), 3a-c (n = 1-5) showed weak inhibitory activities on the uptake of noradrenaline and 5-hydroxytryptamine (5-HT) into hypothalamus vesicles and moderate antagonistic actions to 5-HT2 and H1 in several tissues.

Amoxapine↗
PubMed1989

Effect of 1-(m-chlorophenyl)piperazine and 1-(m-trifluoromethylphenyl)piperazine on locomotor activity.

The piperazine-type 5-hydroxytryptamine (5-HT) agonists 1-(m-trifluoromethylphenyl)piperazine (TFMPP), 1-(m-chlorophenyl)-piperazine (m-CPP), 1-(p-chlorophenyl)piperazine (p-CPP) and MK-212 [6-chloro-2-(1-piperazinyl)pyrazine], produced a dose-dependent suppression of spontaneous ambulatory behavior in rats. Pretreatment with the 5-HT antagonists metergoline, methysergide or mianserin, but not selective 5-HT2 or catecholamine antagonists, blocked the reduction of activity caused by TFMPP suggesting that the stimulation of 5-HT receptors was involved in causing this behavioral effect. Other behavioral signs of 5-HT receptor stimulation, such as the 5-HT behavioral syndrome or head-shaking behavior, were not observed in rats injected with TFMPP, m-CPP or MK-212 except at toxic doses. The ability of piperazine agonists to reduce locomotor activity in rats was altered by long-term changes in 5-HT neurotransmission. The destruction of 5-HT neurons by i.v.t. injection of the neurotoxin 5,7-dihydroxytryptamine potentiated the ability of m-CPP to inhibit ambulatory behavior. On the other hand, elevating 5-HT content by administering the monoamine oxidase inhibitors phenelzine or nialamide for 7 days reduced the ability of m-CPP to suppress locomotor activity. Acute administration of the monoamine oxidase inhibitors, or chronic administration of other antidepressants such as desmethylimipramine or iprindole, failed to alter m-CPPs activity-suppressant effects. These studies suggest that chronic changes in 5-HT neurotransmission produce compensatory changes which alter the behavioral response to these piperazine agonists. Taken together with other evidence that both TFMPP and m-CPP are agonists at 5-HT1B and 5-HT1C receptors, the effects of TFMPP and m-CPP on locomotor activity may be associated with the selective activation of 5-HT1C, or possibly 5-HT1B, receptors.

Animals↗
PubMed1989

Piperazine derivatives of benzimidazole as potential anthelmintics. Part 1: Synthesis and activity of methyl-5-(4-substituted piperazin-1-yl)benzimidazole-2-carbamates.

A series of 5-(4-substituted piperazin-1-yl)-2-nitroanilines (4) and 5-(4-substituted piperazin-1-yl)benzimidazole-2-carbamates (6) has been synthesized starting from 5-chloro-2-nitroaniline (3) and N-monosubstituted piperazines. Catalytic reduction of 4 with Pd/C followed by treatment with 1,3-dicarbomethoxy-S-methylisothiourea yielded the corresponding methyl-5-(4-substituted piperazin-1-yl)benzimidazole-2-carbamates (6) which were for anthelmintic activity against experimental infections of Trichinella spiralis.

Animals↗
PubMed1991

Endogenous formation of N-nitrosamines from piperazine and their urinary excretion following antihelmintic treatment with piperazine citrate.

Antihelmintic treatment with piperazine (1,4-diazacyclohexane) for microfilarie parasitism results in the endogenous formation of piperazine-derived N-nitrosamines. The urinary excretion of these N-nitrosamines was determined by biochemical monitoring of 14 patients receiving 2 g piperazine citrate. The urinary excretion (mean +/- SD) of N-mononitrosopiperazine (MNPz) was 27.0 +/- 26.7 micrograms/day (range 0.6-96.0 micrograms/day). Trace levels of 0.73 +/- 0.92 micrograms/day N,N'-dinitrosopiperazine (DNPz) (range ND-2.8 micrograms/day) were also found in 7 of 14 urine samples. N-Nitroso-3-hydroxypyrrolidine (NHPYR), a metabolite of both MNPz and DNPz, was detected in 11 of 14 urine samples at a mean concentration of 1.74 +/- 1.72 micrograms/day (range ND-5.7 micrograms/day) and traces of N-nitrosodiethanolamine in two samples at levels of 0.3 and less than 0.1 micrograms/day. The results show that biochemical monitoring of urinary NHPYR may be a good indicator of endogenous MNPz formation. While DNPz was also detected in urine, conclusive validation for its endogenous formation could not be provided because no evidence was found for the presence of its major metabolite, N-nitroso-(2-hydroxyethyl)glycine in urine.

Adult↗
PubMed1976

Quantitative determination of piperazine citrate in piperazine citrate syrup USP.

An assay for piperazine citrate in Piperazine Citrate Syrup USP is described. The assay method is based on the formation of a complex of piperazine with an acid dye, bromothymol blue. The complex can be extracted with chloroform and measured spectrophotometrically. The method is accurate and requires only 15 minutes for analysis, compared to four to five hours by the USP method.

Hydrogen-Ion Concentration↗
PubMedDate not supplied

Anticonvulsant activity of the NMDA antagonists, D(-)4-(3-phosphonopropyl) piperazine-2-carboxylic acid (D-CPP) and D(-)(E)-4-(3-phosphonoprop-2-enyl) piperazine-2-carboxylic acid (D-CPPene) in a rodent and a primate model of reflex epilepsy.

D-(-)4-(3-phosphonopropyl)piperazine-2-carboxylic acid (D-CPP) and its unsaturated analogue (D(-)(E)-4-(3-phosphonoprop-2-enyl) piperazine-2-carboxylic acid (D-CPPene) have been administered to DBA/2 mice (intracerebroventricularly, i.c.v., intraperitoneally, i.p., and orally, p.o.) and to photosensitive baboons, Papio papio (intravenously, i.v., and orally), and their effects on reflexly induced epileptic responses assessed. In DBA/2 mice the clonic phase of the seizure response to sound is suppressed by D-CPP with an ED50 of 5.5 micrograms/mouse, i.c.v.; 0.69 mg (2.75 mumol)/kg i.p. and 16.6 mg (65.8 mumol)/kg p.o. compared with, for D-CPPene, 2.2 micrograms/mouse i.c.v., 0.41 mg (1.54 mumol)/kg i.p. and 10.8 mg (40.2 mumol)/kg, p.o. In Papio papio myoclonic responses to stroboscopic stimulation are suppressed 24 and 48 h after D-CPP 32 mg (127 mumol)/kg p.o. Administration of D-CPPene 8-16 mg (30-60 mumol)/kg i.v. produces protection against myoclonic responses after 1-2 h, lasting for 48 h. Oral administration of D-CPPene 32-64 mg (119-239 mumol)/kg produces protection beginning after 4 h and sustained for 48 h. Measurements of plasma D-CPPene concentration show rapid clearance after i.v. injection and a low plasma concentration 1.5-5 h after oral administration. The prolonged anticonvulsant action of D-CPP and D-CPPene following oral administration suggests that these compounds merit evaluation as antiepileptic therapy in man.

Acoustic Stimulation↗
PubMed1990

Synthesis, biological evaluation, and quantitative structure-activity relationship analysis of [beta-(Aroylamino)ethyl]piperazines and -piperidines and [2-[(Arylamino)carbonyl]ethyl]piperazines, -pyrazinopyridoindoles, and -pyrazinoisoquinolines. A new class of potent H1 antagonists.

Some [beta-(Aroylamino)ethyl]piperazines and -piperidines and [2-[(Arylamino)carbonyl]ethyl]piperazines, -piperidines, -pyrazinopyridoindoles, and -pyrazinoisoquinolines have been synthesized and their H1-antagonistic activity studied in isolated guinea pig ileum. Quantitative structure-activity relationship analysis indicates that the hydrophobicity of the side chain of these compounds plays a major role in their activity while steric and electronic factors are of secondary importance. All these compounds act on a common receptor and appear to interact similarly with the receptor.

Amines↗
PubMed1978

Studies on 1-substituted 4-(1,2-diphenylethyl)piperazine derivatives and their analgesic activities. 2. Structure-activity relationships of 1-cycloalkyl-4-(1,2-diphenylethyl)piperazines.

Forty-six 1-cycloalkyl-4-(1,2-diphenylethyl)piperazines were synthesized. The influence of substituents on phenyl groups of 1-cycloalkyl-4-(1,2-diphenylethyl)piperazines 4a-c on the analgesic activity was investigated in experimental animals. The most active compounds, 5a-c, in this series had a m-hydroxyl group on the 2-phenyl group of 4a-c, while morphine has a phenolic hydroxyl group para to th- aminoethyl moiety. Their activities were 23-56 and 23-38 times those of their original compounds 4a-c and morphine, respectively, tested by the D'Amour-Smith method after subcutaneous administration.

Analgesics↗
PubMed1989

Preparation and biodistribution of 1-[2-(3-[125I]iodo-4-aminophenyl)ethyl]-4-[3-(trifluoromethyl) phenyl]piperazine and 1-[2-(3-[125I]iodo-4-azidophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl] piperazine.

The iodinated analogue of 1-[2-(4-aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (PAPP), IPAPP (4), and the corresponding azido compound azido-IPAPP (5) were synthesized. The corresponding no-carrier-added 125I (T1/2 = 60 days, 35-60 keV) labeled compounds were also prepared. High specific binding was observed from in vitro binding studies using rat brain tissue preparation; Ki = 20 and 17.5 nM against [3H]-5-HT. In vivo biodistribution studies in rats showed that azido-[125I]IPAPP passed through intact blood-brain barrier and localized in the brain. Ex vivo autoradiography of rat brain sections exhibited a diffuse uptake pattern, which may be due to specific and nonspecific binding. The results indicate that IPAPP and azido-IPAPP may not be suitable to image the serotonin receptor in the brain.

Animals↗
PubMedDate not supplied

Piperazine derivatives of dimethylxanthines. IV. Reaction of beta,gamma-epoxypropyldimethylxanthines with piperazines.

In the reaction of 7-resp. 1-beta,gamma-epoxyproplderivatives of theophylline (Th) or theobromine (Tb) with piperazine and N-monoalkyl or monoarylpiperazines the corresponding 7-resp. 1-beta-hydroxy-gamma-piperazinopropyl-Th (1-8) resp. Tb (9-16) were formed. In preliminary screening some of the new compounds showed strong antagonism with histamine H1 receptor and with endogenous histamine.

Animals↗
PubMed1990

Sex differences in the effects of 1-(m-trifluoromethylphenyl) piperazine and 1-(m-chlorophenyl) piperazine on copulatory behavior in the rat.

Peripheral administrations of TFMPP (0.2- 1 mg/kg) or MCPP (1 mg/kg) facilitated lordosis behavior in female rats treated with estradiol benzoate, and had no effects in females primed with estradiol benzoate and progesterone. In contrast, TFMPP (1 mg/kg) and MCPP (1 mg/kg) inhibited copulatory behavior in male rats. It is concluded that there are sex differences in the effects of TFMPP and MCPP on copulatory behavior in the rat. Moreover, it is suggested that the effects of these drugs on copulatory behavior may be mediated by activation of 5-HT1B and/or 5-HT1C receptors, or by blockade of activity at 5-HT3 receptors.

Animals↗