The application of 1,3-dioxolane in synthesis of disubstituted 3,4-dihydroquinazolines, diarylmethane or methylenediamine

The interaction between 1,3-dioxolane with primary aromatic amine- sulfanilamide (streptocide), secondary aromatic amine-N-benzylaniline and also with amine of heterocyclic series – 4-aminopyridine. It is found that, sulfanilamide (streptocide), which has an electron withdrawing sulfonamide group in para position, reacts with 1,3-dioxolane in an atmosphere of benzol and trifluoroacetic acid producing 3-(4-sulfamoylphenyl)-3,4-dihydroquinazoline-6-sulphonamide, that is corresponding to the previous result obtained when 1,3-dioxolane reacts with para-nitroaniline (which also contains electron-withdrawing nitrogroup) resulting in 3-(p-nitrophenyl)-6-nitro-3,4-dihydroquinazoline. Under the same conditions the interaction between 1,3-dioxolane and N-benzylaniline results in producing 4,4'-bis(phenylmethyleneamino)diphenylmethane, which refers to a different class of compounds – diphenylmethane derivative. A primary amine of heterocyclic series 4-aminopyridine reacts with 1,3-dioxolane in the presence of concentrated hydrochloric acid producing N,Nʹ-di-(4-pyridinyl)methylenediamine. Antimicrobic properties of received compounds were studied on museum potentially pathogenic microorganism strains: Staphylococcusaureus (strain 906), Candid aalbicans (АТСС 24433), in FSBI «Scientific Centre for Expert Evaluation of Medicinal Products» of the Ministry of Health of the Russian Federation. Only N,Nʹ-di-(4-pyridyl)methylenediamine out of three investigated compounds showed microbiological activity. This compound inhibits growth of Staphylococcus aureus at concentration 62.5 µg/ml, culture death comes from the effect of concentration 125.0 µg/ml. The morphology of compounds was established according to mass spectrometry data, 1Н NMR spectroscopy, the structure of N,Nʹ-di-(4-pyridyl)methylenediamine in the form of chloride was proved using X-ray structural analysis.

First insights into the synthesis of carbo-phospholane and carbo-phospholene oxides

Fifteen-membered ring carbo-mers of five-membered rings are considered in the heterocyclic series of the phosphole oxide and less unsaturated parents. The synthesis of the first carbo-phospholane oxides is achieved by a [14+1] two-step/one-pot macrocyclization route with 86 % yield. Reduction of the latter phosphora-[5]pericyclyne with SnCl­2 allowed consistent 1H and 31P NMR characterization of the corresponding carbo-phospholene, produced with 11 % yield. The ultimate carbo-phosphole oxide could not be isolated, but preliminary results on alternative strategies towards this 14 pz-electron Hückel carbo-aromatic are reported.