The mol-ecule of the title compound, C(4)H(2)N(2)O(4), is located around an inversion center and the four O atoms are in the 2,3,5,6-positions of the piperazine ring. In the crystal, bifurcated N-H⋯O hydrogen bonds link the mol-ecules into a corrugated layer parallel to (101).

Flunarizine, a calcium channel antagonist of the piperazine class, has been labeled with the positron-emitter 18F.4-[18F]Fluoro-4-fluorobenzhydryl chloride was prepared in three steps from no-carrier-added [18F]fluoride ion, and used in the alkylation of N-cinnamylpiperazine to give [18F]flunarizine in 13% radiochemical yield (from [18F]fluoride).

In the title salt, C(16)H(21)N(4) (+)·ClO(4) (-)·0.5C(4)H(4)O(4), fumaric acid mol-ecules, situated across crystallographic inversion centres, are O-H⋯N hydrogen bonded to two protonated 1,4-bis-(4-pyridylmeth-yl)piperazine cations, forming trimolecular units. These construct one-dimensional supra-molecular ribbons by N-H⋯N hydrogen bonding, and further aggregate via π-π inter-actions [shortest...

The title compound, [Zn(C72H44N4O8)(C4H10N2)] or [Zn(TPBP)(pipz] (where TPBP and pipz are 5,10,15,20-tetra-kis-[4-(benzo-yloxy)phen-yl]porphyrinato and piperazine ligands respectively), features a distorted square-pyramidal coordin-ation geometry about the central Zn(II) atom. This central atom is chelated by the four N atoms of the porphyrinate anion and further coordinated by a nitro-gen atom...

In vitro affinity for vascular 5HT2 and alpha receptors was determined for several compounds (spiperone, ketanserin, mianserin, trazodone, mepiprazole, benzoctamine, m-trifluoro-methylphenylpiperazine, m-chlorophenylpiperazine, and 1-(1-naphthyl)piperazine) known to interact with serotonin receptors. All compounds competitively inhibited 5HT2 and alpha receptors with differing degrees of select...

The crystal and molecular structure of the title compound,C24H36CoN10O(4).2(NO3).3(H2O).Cl, have been determined by X-ray analysis: Cc (No: 9), a = 17.6920(4) A, b = 11.8163(2) A, c = 16.4752(4) A, Beta = 91.679(1) degrees , Z = 4. The Co(III)ion is six-coordinated with octahedral geometry, the pyridine rings are planar and the piperazine rings assume chair conformations.

The asymmetric unit of the title compound, C(18)H(18)N(2)O(2), consists of two independent mol-ecules, each of which is located about a center of inversion. The mol-ecules are not planar, showing dihedral angles of 55.84 (9) and 54.10 (8)° between the piperazinedione and the aromatic rings. The piperazine N atoms exhibit a planar configuration. The crystal packing is stabilized by inter-molecul...

A group of benzimidazole analogs of sildenafil, 3-benzimidazolyl-4-methoxy-phenylsulfonylpiperazines 2-4 and 3-benzimidazolyl-4-methoxy-N,N-dimethyl- benzenesulfonamide (5), were efficiently synthesized. Compounds 2-5 were characterized by NMR and MS and contrary to the reported mass spectra of sildenafil, the spectra of the piperazine-containing compounds 2-4 showed a novel fragmentation patte...