Zinc-Containing Polymers and Their Latexes: Structure and Properties

This work deals with the polymer latexes synthesized using zinc-containing monomers. The effect of the ligand environment of the zinc-containing monomers on the colloidal and rheological properties of the latexes, as well as on mechanical properties of their films is studied. Mixed zinc salts containing the residues of saturated and unsaturated carboxylic acids are shown to be more efficient cross-linking agents than the symmetric salts of this metal.     

4-(Isoindolin-5-yl)amino-4-oxobutyryl-β-alkoxyphenyl-β-alanines, new RGDF mimetics. Synthesis, affinity to fibrinogen receptors, antiaggregatory properties, and their correlation with the hydrophobicity

A new series of RGDF mimetics, derivatives of 4-(isoindolin-5-yl)amino-4-oxobutanoic acid, was synthesized. The compounds obtained inhibit efficiently the thrombocytes aggregation in experiments in vitro; their biological targets are fibrinogen receptors. The antiaggregatory activity and the affinity correlate with the hydrophobicity of the compounds.     

Dipyrrolo[1,2-a;2':,1'-c]pyrazines. 7. Electrophilic Substitution of Dipyrrolo[1,2-a;2',1'-c]pyrazines and 5,6-Dihydrodipyrrolo[1,2-a;2',1'-c]pyrazines via Formylation of Dipyrrolo[1,2-a;2':,1'-c]pyrazines

A series of previously unreported aldehydes has been prepared by the formylation reaction of dipyrrolo[1,2-a;2':,1'-c]pyrazines and their 5,6-dihydro analogs by DMF and phosphorus oxychloride.     

Conversion of pyrrolo[1,2-α]pyrazinium salts to 8-aminoindolizines

The recyclization of pyrrolo[1,2-a]pyrazinium salts under the influence of a base leads to 8-aminoindolizine derivatives and is a new method for the synthesis of indolizines, as well as the first example of the Kost—Sagitullin rearrangement in the pyrazine series.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 763–766, June, 1991.     

Dipyrrolo[1,2-a;2',1'-c]pyrazines. 6. Electrophilic Substitution in a Series of Dipyrrolo[1,2-a;2',1'-c]pyrazine and 5,6-Dihydrodipyrrolo[1,2-a;2',1'-c]pyrazine Derivatives. Phosphorylation of Dipyrrolo[1,2-a;2',1'-c]pyrazines

We have studied the behavior of asymmetrically substituted dipyrrolo[1,2-a;2',1'-c]pyrazines and their 5,6-dihydro analogs under phosphorylation reaction conditions.     

Trifluoroacetylation of pyrrolo[1,2-<Emphasis Type="Italic">a</Emphasis>]pyrazines

A study was carried out on the reaction of pyrrolo[1,2-a]pyrazines containing an alkyl, aryl, or aralkyl substituent at C-1 with trifluoroacetic anhydride. Trifluoroacetylation products may be formed either by reaction in the pyrrole ring or at the aryl or aralkyl groups at C-1. Products of electrophilic substitution at C-6 are formed in the trifluoroacetylation of pyrrolo[1,2-a]pyrazines containing at C-1 a substituent bulkier than a methyl group but lacking substituents at C-6 (the α-position of the pyrrole ring). __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1226–1233, August, 2007.     

Chlorination of 2-substituted 1-hydroxyindoles

Russian Chemical Bulletin - Chlorination of 1-hydroxyindole-5,6-dicarbonitriles and 1-hydroxypyrrolo[3,4-f]indole-5,7(1H,6H)-diones with N-chlorosuccinimide afforded previously unknown...     

On differential-geometric structures on a manifold of nonholonomic (<Emphasis Type="Italic">n</Emphasis> + 1)-web

We consider a nonholonomic (n + 1)-web NW on an n-dimensional manifold M, i.e., n + 1 distributions of codimension 1. We prove that there exists an invariant pencil of projective connections on M. To an ordered nonholonomic (n + 1)-web on M, there corresponds a unique curvilinear (n + 1)-web on M and vice versa. This correspondence is defined by the polarity with respect to a certain invariant multilinear n-form or the barycentric subdivision of some (n - 1)- dimensional simplex. In conclusion, we consider, as a special case, a nonholonomic (n + 1)-web ANW of hyperplanes in the affine space. A web ANW generates an invariant pencil of affine connections. We also study the case when these connections are projective.     

Completion of the group topology of a countable group

Kishinev. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 31, No. 1, pp. 3–13, January–February, 1990.