A new bicyclic aziridino lactone 1 was synthesized from methyl 2,3-dibromopropionate and 2-amino-2-methylpropane-1,3-diol (AMPD). The reaction of compound 1 with benzyl chloroformate and subsequent treatment of the intermediate compound with 1,8-diazabicyclo[5.4.0]undec-7-ene gave a bicyclic lactone, 4,8-dioxa-1-azabicyclo[4.3.0]nonane-3,9dione.

Reaction of 1,10-bis(methoxymethyl)-1,10-diaza-18-crown-6 ( 1 ) with trimethylsilyl azide resulted in hitherto unknown 1,10-bis(azidomethyl)-1,10-diaza-18-crown-6 ( 2 ) and novel ionic compound 1,10-bis(azide anion)-1,10-dihydro-1,10-diaza-18-crown-6 ( 3 ). Compound 2 rnneacted with dimethyl acetylenedicarboxylate to give 1,10-bis(4,5-dimethoxycarbonyltriazolomethyl)-1,10-diaza-18-crown-6 ( 4 ). Carbamoylation of 1,10-diaza-18-crown-6 ( 5 ) with optically active α-phenylethyl amine yielded optically active 1,10-bis(α-phenylethylcarbamoyl)-1,10-diaza-18-crown-6 ( 6 ).

Diastereoselective transformations of Leakadine were discovered: dimerization during melting or heating in CHCl 3 with the formation of one diastereomer. The obtained dimer reacts with methyl isocyanate under mild conditions with the formation of an N -methylcarbamoyl derivative – also in the form of one diastereomer. In the diastereoselective reaction of Leakadine with dimethyl formamide dimethyl acetal, 2-dimethylamino-1,3-diazabicyclo[3.1.0]hexan-4-one was obtained. The reaction of Leakadine with perfluoroisobutylene was studied.

Chiral dialkyl- and tetraalkylglycolurils have been obtained using chiral (S)-(+)- and (R)-(-)-1-sec-butyl-3-methylurea as starting materials. The diastereomer (S)-(+)-2,6-di-sec-butyl-4,8-dimethyl-2,4,6,8-tetraazabicyclo[3.3.0]-octane-3,7-dione was separated into stereoisomers, for the higher melting of which the absolute configuration was determined as (S,S,S,S) by X-ray structural analysis.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The conformations and anomeric effects for 1-3 in solution and for 3 in the solid state were investigated. The resolution of 1 by enantioselective gas chromatography was carried out and activation parameters of inversion in 1 were determined. The asymmetric transformation of the title compounds in an optically active solvent is discussed.

The enantiomers of asymmetric nitrogen compound 1 have been resolved; a chiral formal meso-form of diaziridine 2 has been obtained; a population of 1,2-cis-form 6a in solution has been found; and the crystal structures of 3–6 have been studied.

The spontaneous resolution of conglomerates of a dibenzo analogue of Troger's base 1 and aziridine 2, as well as the second-order asymmetric transformation of (+/-)-1 into a single enantiomer were carried out for the first time.

For the first time, spontaneous resolution of trans-dihydroxyimidazolidin-2-one 1a was performed and racemisation of (-)-1a was studied; regiospecific reaction of 1a-c with aminoguanidine resulted in derivatives 2a-c; compound 2b was also shown to undergo spontaneous resolution, and the absolute configuration (4R,5R) of (-)-2b crystals was established by X-ray diffraction analysis.

The resolution of enantiomers by chiral chromatography and the determination of nitrogen inversion activation parameters by dynamic chromatography have been carried out for aziridines 1–3; the structures of aziridines 4–7 have been studied; the complete diastereomeric transformation of (S,R)-(+)-8a into (R,R)-(–)-8b has been performed, and the conglomerate of high-melting diastereomer (±)-9 has been found.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The psychotropically active drug Albicar 1 has been prepared for the first time in both enantiomerically pure forms starting from the (+)-2 and (–)-2 precursors obtained by spontaneous resolution; the crystal structures of (–)-1 and (±)-1 have been solved by X-ray diffraction study.

The title salt crystallises as a conglomerate (space group P2(1)2(1)2(1), Z = 4) With one solvate CHCl3 molecule forming strong shortened contact with I-[Cl . . .I- 3.599(2) Angstrom]. Therefore, it undergoes spontaneous resolution by simple crystallisation with a deficiency of the conglomerator CHCl3 or by an internal entrainment procedure. It exhibits the (S)-(+) absolute configuration and racemises in solution (DeltaG(rac)(#): = 26.5 kcal mol(-1)). The salt was almost completely converted into one enantiomer by stirred crystallisation from solution (with full evaporation) or from a melt under conditions of enantiomerisation. The contribution of autocatalysis to this process is discussed.

The electronic spectrum of an aqueous solution of an equimolar mixture of nitrogen betaine (pK1 = 1.72, pK2 = 3.62) and hexacyanoferrate anions exhibited a charge-transfer band at 26100 cm–1, which is indicative of the outer-sphere association of these ions.

2,6-Dimethylglycoluril 1 crystallises to form a conglomerate (space group P21) and co-crystallises with isomeric 2,8-dimethylglycoluril 2; 2,6-diethylglycoluril A is the best precursor in the synthesis of chiral drugs.

For 1-methoxymethylaziridine 1 it is proved experimentally (GED) and theoretically that the equilibrium conformers are stabilised by the anomeric effects n(N) --> sigma*(C-O) and n(O) --> sigma*(C-N), whereas in the case of methoxymethyldimethylamine 2 the calculations predict the existence of a conformer appropriate to the n(N) --> sigma*(C-O) effect.

Racemic mixtures 1a–f, 2a–e crystallise as conglomerates at room temperature and lead to spontaneous resolution; tosylimines 1e and 2c give homochiral crystals (space group P1), whereas similar benzenesulfonyloximes 3a,b give heterochiral packings (space groups P21/n and P21/c, respectively).