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In this work we investigated the structural behaviour of a CaMn0.5Zr1.5(PO4)3. Due to the presence of divalent Mn2+ cations this compound can possess interesting luminescence properties. It was recently understood that this phosphate undergoes a temperature induced irreversible phase transition in the range of 800–875 °C. It has also been shown that the 3d–3d luminescence of Mn2+ increases 10 fold for the high temperature polymorph. To determine the Mn environment structural investigations of both phases have been performed by the X-ray powder diffraction and Raman spectroscopy methods. The low temperature modification adopts the trigonal NZP structure type with a slightly lower symmetry (space group R32, a=8.7850(2) A, c=22.6496(7) A, V=1514.8(1) A3). The high temperature form in turn has orthorhombic symmetry (space group Pnma, a=6.2350(3) A, b=6.6281(3) A, c=14.4731(6) A, V=598.13(5) A3). Both structures were solved ab-initio from powder data and structural analysis was performed. In-situ and RT Raman spectra are consistent with the XRD derived structural model. Mn2+ cations occupy different types of positions in these structures and a change in Mn coordination number (6 for LT phase, 7 for HT phase) results in different Mn–O bond lengths. These differences may explain the change in the optical properties between the polymorphs.

Since the discovery of piracetam its structural analogs based on the pyrrolidin-2-one pharmacophore have aroused great interest as a source of effective pharmacological central nervous system agents capable to facilitate memory processes and to attenuate the impairment of cognitive functions associated with head traumas, stroke, age, and age-related pathologies. The present review summarizes the data published during the last decade concerning the design, synthesis, and biological activity exploration of enantiomerically pure (4R)-2-oxo-4-phenylpyrrolidine-1-carboxamide ((R)-phenylpiracetam) and (4R,5S)-5-methyl-2-oxo-4-phenylpyrrolidine-1-carboxamide (E1R) and providing evidence for the direct relationship between the configuration of the stereocenters and biological properties of the respective enantiomers. The methodological approaches leading to the preparation of the single stereoisomers of molecules with one or two chiral centers are reviewed. The results of comparative pharmacological testing of individual enantiomers provides the evidence of their pharmacological advantages, justifying the choice of the most effective stereoisomer and the necessity for drug substance purification from the less active one(s).

Interaction of polyfluorinated chalcones (pentafluorobenzalacetophenone, benzalpentafluoroacetophenone and decafluorochalcone) with 1,2-diaminobenzene in alcohols in the presence of triethylamine or quaternary ammonium salt (TEBAC) has been investigated. In the presence of TEBAC in 2-propanol polyfluorinated 2,4-diaryl-2,3-dihydro-1H-1,5-benzodiazepines are formed. Some of them undergo intramolecular fluorine substitution and unusual rearrangement into a previously unknown polyfluoro-containing tetracyclic compounds—(6aR)-1,2,3,4-tetrafluoro-6a-aryl-6a,7-dihydrobenzimidazo[1,2-a]quinolines, under the reaction conditions as well as in absence of TEBAC. The structures are established on NMR spectra and confirmed by X-ray.

The method is based on the condensation of preformed or in situ generated α-furyl substituted azaheterocycles with acryloyl chloride or maleic anhydride via N-acylation and intramolecular Diels—Alder reaction of the furan moiety.

An effective method for the conversion of 1-acetyl-4-phenyl-2-pyrrolidone into 1-acetyl-4-phenyl-3-pyrrolin-2-one by bromination–dehydrobromination with N-bromosuccinimide, catalyzed by azo-bisisobutyronitrile or by UV irradiation is developed. The method was extended to the 1-acetyl-4-phenyl-3-pyrrolin-2-one structural analogs. An employment of an excess of N-bromosuccinimide under given reaction conditions leads to the bromination of 1-acetyl-4-phenyl-3-pyrrolin-2-one and its structural analogs at position 5.

X-ray diffraction shows that compounds isostructural with the oxygen ion conductor La2Mo2O9 exist in the ternary systems La2Mo2O9—Nd2W2 O9—Nd2Mo2O9 and La2Mo2O9—Pr2W2 O9—Pr2Mo2O9 over wide single-phase regions.

Dehydration of 2-(3,3-dimethyl-1-oxo-2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]-diazepin-11-yl)benzoic acid (3a) and 2-(3,3-dimethyl-1-oxo-2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e] [1,4]diazepin-11-yl)-5,6-dimethoxybenzoic acid (3b) in boiling acetic or propionic anhydride gave 7,7-dimethyl-4b,7,8,9-tetrahydro-6H-dibenzo[2,3:5,6][1,4]diazepino[7,1-a]-isoindole-5,15-dione (5a) and 1,2-dimethoxy-7,7-dimethyl-4b,7,8,9-tetrahydro-6H-dibenzo-[2,3:5,6][1,4]diazepino[7,1-a]isoindole-5,15-dione (5b), respectively. The products obtained are representatives of a novel fused pentacyclic system. The structures of compounds 3b and 5a were unambiguously proved by X-ray diffraction.

New aminophthalides (III) are synthesized by reaction of o-formylbenzoic acid with substituted 2-aminothiophenes.

Polyfluorinated di-and triarylpyrazolines were synthesized by the reactions of polyfluorinated chalcones with hydrazine hydrate and phenylhydrazine, respectively. Reactions of benzyl-idenepolyfluoroacetophenones with phenylhydrazine resulted in the mixtures of isomeric 1,5-diphenyl-3-polyfluoroaryl-and 1,3-diphenyl-5-polyfluoroarylpyrazolines. Fluorescence properties of the synthesized triarylpyrazolines were studied.

Reactions of α-perfluorophenylpyrylium salts with hydrazine hydrate in ethanol afforded derivatives of 1,2-diazepine, dihydro-1H-pyrazole, and/or 1-aminopyridinium salts, depending on the steric characteristics of the substituent in the second α-position. 1-Amino-2-methyl-6-perfluorophenyl-4-phenylpyridinium perchlorate was used to obtain various pyridocyanines.

Summarized are reactivity studies of binuclear ladder complexes in the metallation reaction that has been applied to prepare novel homo- and heteropolynuclear transition metal complexes. The electron transfer through π-ligand-metal-σ,π-ligand-metal chain has been studied by IR spectroscopy and cyclic voltammetry techniques.

A new synthesis of phthalimidines is described. 3-Acyloxy-2-aryl- and 2-acylamino-3-acyloxyphthalimidines were prepared by the reaction of 3-arylaminophthalides or o-formylbenzoic acid acylhydrazones with acetic or propionic anhydrides. Their reactions with O-, N-, S-, and C-nucleophiles were studied. The structure of 2-acetyl(cyanoacetyl)amino-3-acetoxyindolin-1-one was confirmed by X-ray diffraction analysis.

The disodium salt of (4R,5R)-(TADDOL),3, can be used as a mediator in the asymmetric Michael reactione.g. 1,4-addition of a glycine synthon 1 to methyl methacrylate 2, mediated by 3 (10-100 mol%), gives a diastereoisomeric excess of the corresponding product 4 up to 65% and an enantiomeric purity ca. 28%; (2S,4R)-4-methylglutamic acid (ee ≥ 85%), 6, was obtained starting from (2S,4R)-4 (ee 28%) through the recrystallization and decomposition of the latter.