1-(Indolylalkyl)-4-Arylpiperazines: A New Class of Tranquilizers

The structures of eleven (4-phen-yl)piperazinium salts containing organic anions

Eleven (4-phen-yl)piperazinium salts containing organic anions have been prepared and structurally characterized, namely, 4-phenyl-piperazin-1-ium 4-fluoro-benzoate monohydrate, C₁₀H₁₅N₂ ⁺·C₇H₄FO₂ ^-·H₂O, 1; 4-phenyl-piperazin-1-ium 4-bromo-benzoate monohydrate, C₁₀H₁₅N₂ ⁺·C₇H₄BrO₂ ^-·H₂O, 3; 4-phenyl-piperazin-1-ium 4-iodo-benzoate, C₁₀H₁₅N₂ ⁺·C₇H₄IO₂ ^-, 4; 4-phenyl-piperazin-1-ium 4-nitro-benzoate, C₁₀H₁₅N₂ ⁺·C₇H₄NO₄ ^-, 5; 4-phenyl-piperazin-1-ium 3,5-di-nitro-salicylate, C₁₀H₁₅N₂ ⁺·C₇H₃N₂O₇ ^-, 6; 4-phenyl-piperazin-1-ium 3,5-di-nitro-benzoate, C₁₀H₁₅N₂ ⁺·C₇H₃N₂O₆ ^-, 7; 4-phenyl-piperazin-1-ium picrate, C₁₀H₁₅N₂ ⁺·C₆H₂N₃O₇ ^-, 8; 4-phenyl-piperazin-1-ium benzoate monohydrate, C₁₀H₁₅N₂ ⁺·C₇H₅O₂ ^-·H₂O, 9; 4-phenyl-piperazin-1-ium p-toluene-sulfonate, C₁₀H₁₅N₂ ⁺·C₇H₇O₃S^-, 10; 4-phenyl-piperazin-1-ium tartarate monohydrate, C₁₀H₁₅N₂ ⁺·C₄H₅O₆ ^-·H₂O, 11; and 4-phenyl-piperazin-1-ium fumarate, C₁₀H₁₅N₂ ⁺·C₄H₃O₄ ^-, 12. Compounds 1 and 3-12 are all 1:1 salts with the acid proton transferred to the phenyl-piperaizine basic N atom (the secondary amine) with the exception of 3 where there is disorder in the proton position with it being 68% attached to the base and 32% attached to the acid. Of the structures with similar stoichiometries only 3 and 9 are isomorphous. The 4-phenyl substituent in all cases occupies an equatorial position except for 12 where it is in an axial position. The crystal chosen for structure 7 was refined as a non-merohedral twin. There is disorder in 5, 6, 10 and 11. For both 5 and 6, a nitro group is disordered and was modeled with two equivalent orientations with occupancies of 0.62 (3)/0.38 (3) and 0.690 (11)/0.310 (11), respectively. For 6, 10 and 11, this disorder is associated with the phenyl ring of the phenyl-piperazinium cation with occupancies of 0.687 (10)/0.313 (10), 0.51 (7)/0.49 (7) and 0.611 (13)/389 (13), respectively. For all salts, the packing is dominated by the N-H⋯O hydrogen bonds formed by the cation and anion. In addition, several structures contain C-H⋯π (1, 3, 4, 8, 9, 10, and 12) and aromatic π-π stacking inter-actions (6 and 8) and one structure (5) contains a -NO₂⋯π inter-action. For all structures, the Hirshfeld surface fingerprint plots show the expected prominent spikes as a result of the N-H⋯O and O-H⋯O hydrogen bonds.

Palladium/norbornene chemistry: an unexpected route to methanocarbazole derivatives via three Csp3–Csp2/Csp3–N/Csp2–N bond formations in a single synthetic sequence

A simple route to obtain fused indolinesviaa palladium-catalyzed norbornene-mediated Heck reaction/C–H activation/double amination cascade is described.

N-arylpiperazinyl-N'-propylamino derivatives of heteroaryl amides as functional uroselective alpha 1-adrenoceptor antagonists

Novel arylpiperazines were identified as alpha 1-adrenoceptor (AR) subtype-selective antagonists by functional in vitro screening. 3-[4-(ortho-Substituted phenyl)piperazin-1-yl]propylamines were derivatized with N,N-dimethyl anthranilamides, nicotinamides, as well as carboxamides of quinoline, 1,8-naphthyridine, pyrazolo[3,4-b]pyridine, isoxazolo[3,4-b]pyridine, imidazo[4,5-b]pyridine, and pyrazolo[1,5-a]pyrimidines. Strips of rabbit bladder neck were employed as a predictive assay for antagonism in the human lower tract. Rings of rat aorta were used as a "negative screen" for the test antagonists. Binding to alpha 1-ARs was relatively sensitive to size and electronic features of the arylpiperazine portion of the antagonists and permissive to these features on the heteroaryl carboxamide side. These structure-affinity findings were exploited to produce nicotinamides (e.g. 13ii and 25x) and pyrazolo[3,4-b]pyridines (e.g. 37f and 37y) ligands with nanomolar affinity at the alpha 1-AR subtype prevalent in the human lower urinary tract(pA2 values: 8.8, 10.7, 9.3, and 9.9, respectively) and displaying 2-3 orders of magnitude selectivity over the alpha 1D-AR.

Identification and quantitation of 1-arylpiperazines, metabolites resulting from side-chain cleavage of (4-substituted aryl-1-piperazinyl)alkyl heterocyclic derivatives in rat plasma and brain

Many drugs contain the arylpiperazine moiety in the side-chain of their molecules. A common metabolic pathway of such drugs is cleavage of the side-chain with the formation of 1-arylpiperazines. This has been verified by combined gas chromatography-mass spectrometry of biological samples from rats given orally a series of heterocyclic derivatives bearing a 4-aryl(phenyl, pyrimidinyl, pyridyl or thiazolyl)-1-piperazinylalkyl moiety (oxypertine, zolertine, millipertine, empiprazole, dapiprazole, antrafenine, piribedil, azaperone). A sensitive and selective electron-capture gas-liquid chromatographic procedure for 1-arylpiperazines in rat plasma and brain is described. The overall recovery from plasma and brain was 70-90%. The limit of detection for substituted (halogenated) phenylpiperazines was 10-25 ng/ml or ng/g and 25-100 ng/ml or ng/g for other derivatives. Preliminary data are reported on the time course of the production and elimination of 1-arylpiperazines after oral administration of representative compounds with the arylpiperazine moiety (oxypertine, azaperone and S-3608).

A comparison of the effects of oxypertine and trifluoperazine in withdrawn schizophrenics

There is a growing body of evidence that oxypertine (Win. 18,501), a recently developed indolylalkyl-phenyl-piperazine (1, 9), is of value in the treatment of schizophrenia (6). Oxypertine has been described as superior to trifluoperazine in its effect on certain aspects of schizophrenic behaviour (2, 5).

A comparison of the effects of varying dose levels of oxypertine on mood and physical performance of trained athletes

Oxypertine (also known as Win. 18,501–2) is a member of a series of alkyl indolyl-4-phenyl piperazines (Archer et al., 1962), and is 1-[2-(5,6 -Dimethoxy-2-methyl-3-indolyl) ethyl]-4-phenylpiperazine.

Oxypertine. A review of clinical experience

Oxypertine (also known as WIN 18,501–2) is a member of a new series of indolylalkylphenyl-piperazines synthesized by Archer et al (1). It resembles serotonin in respect of its indole nucleus, and the piperazine side-chain indicates a structural relationship with some of the major phenothiazines. Pharmacological studies by Wylie and Archer (17) showed oxypertine to have tranquillizing properties, and following preliminary human tolerance investigations (15) the psychotherapeutic nature of the agent was investigated by various workers in the United States and Europe.

A COMPARATIVE STUDY OF OXYPERTINE AND TRIFLUOPERAZINE IN CHRONIC SCHIZOPHRENIA--A NEW APPLICATION OF THE WING RATING SCALE

A new series of compounds thought to have some of the properties of major tranquillizers has recently been synthesized (Archer et al., 1962). One of these, oxypertine (Fig. 1) has been made available to us under its code name, WIN.18, 501. Pharmacological studies have shown oxypertine to have tranquillizing, anti-adrenergic and hypotensive properties (Wylie and Archer, 1962).