Reaction of 2-Isopropyl-5,6-benzo-1,3,2-oxazaborepane with Acetonitrile

Russian Journal of General Chemistry -     

Fragmentation of RGD-peptidomimetics,derivatives of 7-amino-1,2,3,4-tetrahydroisoquinoline and isophthalic acid,by fast atom bombardment mass spectrometry in positive and negative ion modes

Fragmentation pathways of a series of RGD-peptidomimetics, derivatives of 7-amino-1,2,3,4-tetrahydroisoquinoline and isophthalic acid, were studied by fast atom bombardment mass spectrometry in positive and negative ion modes. Structural factors affecting the formation of fragment ions were determined.     

The properties and structure of N-chloro-N-methoxy-4-nitrobenzamide

The XRD study of N-chloro-N-methoxy-4-nitrobenzamide revealed the high pyramidality degree of its amide nitrogen atom in O–N–Cl moiety. N-Chloro-N-methoxy-4-nitrobenzamide reacts with AcONa in MeCN selectively forming N-acetoxy-N-methoxy-4-nitrobenzamide, whereas its methanolysis in the presence of AcONa yields N,N’-bis(4-nitrobenzoyl)-N,N’-dimethoxyhydrazine.     

1-Alkoxyamino-4-dimethylaminopyridinium derivatives as new representatives of O–N–N+ geminal systems and their structure2

N-Alkoxy-N-(4-dimethylaminopyridin-1-ium-1-yl)-substituted ureas, benzamides and N-tert-alkylamines were prepared by the reac tion of the corresponding (N-chloro-N-alkoxy)amino compounds with 4-dimethylaminopyridine. The XRD study of N-alkoxy-N-(4-dimethylaminopyridin-1-ium-1-yl)ureas has revealed the high pyramidality of the central nitrogen atom in O–N–N+ geminal system.     

The Young’s Modulus of a Zigzag CNT/Graphene Composite by Tension along the Graphene Direction

Physics of the Solid State - The Young’s modulus of a finite-sized zigzag carbon nanotube-based ribbon-like columnar graphene is theoretically studied. The dependence of elastic...     

Synthesis of derivatives of p-tert-butylcalix[4]arene containing on lower rim fragments of 2-aminoalkylbenzimidazoles

Reactions of calix[4]arene carboxymethoxy derivatives with 2-aminoalkylbenzimidazoles in the presence of dicyclohexylcarbodiimide and hydroxybenzotriazole afforded a series of p-tert-butylcalix[4]arene derivatives containing on the lower rim N-(2-benzimidazolylalkyl)carbamoylmethoxy fragments. The reaction carried out in the absence of hydroxybenzOtriazole resulted in macrocycles containing one N-(2-benzimidazolylalkyl)carbamoyl fragment and a fragment of N-(acyl)dicyclohexylisourea.     

Tin(IV) complexes with 2-hydroxybenz-(2-hydroxynaphth)aldehyde picolinoylhydrazones (H2Ps, H2Pnf). Crystal structure of [SnCl3(Ps · H)] · CH3OH and [SnCl3(Pnf · H)] · CH3OH

The reactions of SnCl₄ with picolinoylhydrazones of 2-hydroxybenz-(2-hydroxynaphth)aldehydes (H₂Ps, H₂Pnf) in CH₃OH gave non-electrolyte complexes [SnCl₃(Ps · H)] · CH₃OH (I) and [SnCl₃(Pnf · H)] · CH₃OH (II). The imide form of the ligand coordinated to Sn(IV) through the azomethine nitrogen atom and oxyazine and oxy oxygen atoms was proved by UV/Vis, IR, and ¹H NMR spectroscopy. The negative charge on the coordination unit thus arising is counterbalanced by the positive charge caused by the protonation of ligands at the pyridine nitrogen atom of the heterocycle. It was shown that dehydrochlorination of the complexes affords tin-containing species, which correlates with the presence of the corresponding peaks [SnCl₂(Ps)]⁺ and [SnCl₂(Pnf)]⁺ in their mass spectra. The molecular and crystal structures of complexes I and II were determined by X-ray diffraction.