Synthesis, structure, and antibacterial activity of aminobenzofuroxan and aminobenzofurazan

The amination of 4,6-dichloro-5,7-dinitrobenzofuroxan and 4,6-dichloro-5,7-dinitrobenzofurazan with dibenzylamine followed the aromatic nucleophilic substitution pattern (S_NAr) and gave products of replacement of both chlorine atoms in the six-membered ring with elimination of hydrogen chloride. Regardless of the reactant ratio, 4,6-dichloro-5,7-dinitrobenzofuroxan was converted into 4,6-bis(dibenzylamino)-5,7-dinitrobenzofuroxan, whereas 4,6-dichloro-5,7-dinitrobenzofurazan under analogous conditions gave rise to unusual bisammonium derivative which lost proton from the amino group on C⁴ and benzyl group from the amino group on C⁶; as a result, the corresponding diamine with secondary and tertiary nitrogen atoms was obtained. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and X-ray analysis; their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry.     

Efficient synthesis of 4-O- and C-substituted-7-azaindoles

6-Chloro-4-nitro- and 4,6-dichloro-1H-pyrrolo[2,3-b]pyridine are versatile building blocks that allow the synthesis of 4-substituted 7-azaindole derivatives by simple nucleophilic displacement of the 4-substituent. Herein, we report on their reaction with phenolates and activated methylene nucleophiles.     

Synthesis of 6-substituted 9-(dihydroxyalkyl) purines

5-Amino-6-chloro-4-dihydroxyalkylaminopyrimidines, which are cyclized to 6-chloro-9-(dihydroxyalkyl)purines, were obtained by the condensation of 5-amino-4,6-dichloropyrimidine with 2-amino-1,3-dihydroxypropane or with 2-amino-1,4-dihydroxybutane. The corresponding 6-hydroxy and 6-amino derivatives were obtained by replacement of the chlorine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 262–264, February, 1971.     

Nitro derivatives of cyclic sulfoximides of the 1,2-benzoisothiazole series

Nitro derivatives of 1-R-1,2-benzoisothiazol-3-one 1-oxide were synthesized by the reactions of 2-alkyl(phenyl)thio-4-nitro- and 4,6-dinitro-2-(phenylthio)benzamides with chlorine in 60% acetic acid. Analogous reactions of 2-(n-butylthio)-4-nitro- and 2-(tert-butylthio)-4-nitrobenzamides with chlorine afforded 2-butyl- and 2-H-1,2-benzoisothiazol-3-one 1-oxides, respectively. The proposed reaction mechanism includes the formation and subsequent transformations of S-alkyl-S-aryl- and S,S-diarylchlorosulfonium chlorides.     

Catalytic and Noncatalytic Ammonolysis of Chloropentafluorobenzene

Ammonolysis of chloropentafluorobenzene both in the presence and in the absence of copper(I) salt results mainly in replacement of the para- and ortho-fluorine atoms with respect to chlorine rather than replacement of the chlorine atom. Ammonolysis of 4-chloro-2,3,5,6-tetrafluoroaniline and 2-chloro-3,4,5,6-tetrafluoroaniline in the absence of copper(I) salt yields exclusively the corresponding fluorine substitution products, whereas in the presence of copper(I) salt the chlorine atom is replaced. Successive ammonolysis of chloropentafluorobenzene in the presence of copper catalyst along these two paths was put into the basis of a new method for preparation of 2,3,5,6-tetrafluoro-1,4-phenylenediamine.     

Synthesis of 3-substituted 1-aryl-4,6-dinitro-1H-indazoles based on picrylacetaldehyde and their behavior in nucleophilic substitution reactions

A method for the synthesis of 1-aryl-3-formyl-4,6-dinitro-1H-indazoles by the reaction of picrylacetaldehyde with aryldiazonium salts followed by intramolecular cyclization of the resulting picrylglyoxal monoarylhydrazones was developed. Various 4,6-dinitro-1-phenyl-1H-indazoles substituted in position 3 were prepared via transformations involving the formyl group of 3-formyl-4,6-dinitro-1-phenyl-1H-indazole. 3-R-4,6-Dinitro-1-phenyl-1H-indazoles (R = CHO, CN, 1,3-dioxolan-2-yl) react regiospecifically with anionic O-, S-, and N-nucleophiles, in particular, with replacement of only the 4-NO₂ group. Thus previously unknown 3-R-4-Nu-6-nitro-1-phenyl-1H-indazoles were synthesized (Nu is a nucleophile residue).     

Reactions of azoles with tetrachloro-1,2-difluoroethane and 1,2-dichlorodifluoroethylene

Tetrachloro-1,2-difluoroethane reacted with pyrazole and imidazole sodium salts to give mixtures of the corresponding N-(1,2,2-trichloro-1,2-difluoroethyl) derivatives and (E)-1,2-difluoro-1,2-dihetarylethenes. (E)-1,2-Difluoro-1,2-di(3,5-dimethyl-1H-pyrazol-1yl)ethene was also obtained as a result of replacement of chlorine atoms in 1,2-dichloro-1,2-difluoroethene. Analogous reaction with more nucleophilic imidazole involved replacement of not only chlorine but also fluorine atoms in 1,2-dichloro-1,2-difluoroethene, yielding tetraimidazolyl-substituted ethylene.     

Chemoselective cyclocondensation of α-acylacetamidines with 2-methylsulfanyl-4,6-dichloropyrimidine-5-carbaldehyde

Cyclocondensation of α-acylacetamidine with 2-methylsulfanyl-4,6-dichloropyrimidine-5-carbaldehyde proceeds chemo- and regioselectively involving replacement by the α-carbon of the amidine of the chlorine in the aromatic ring and a reaction of the amino group with the formyl group.     

Kinetics of the Reactions of 4-Nitrochlorobenzene with Substituted Phenolates in an Aprotic Polar Solvent

The kinetics of 4-nitrochlorobenzene reactions with substituted phenolates in the medium of N,N-dimethylacetamide was studied. The BrØnsted relation is fulfilled by substituted potassium phenolates: the nucleophilicity of phenolates increases with an increase in their basicity. The rate-limiting step in the reactions of 4-nitrochlorobenzene with substituted phenolates and potassium resorcinate is changed from the phenoxide anion to the phenoxide dianion. In the latter case, electron transfer from the resorcinate dianion with the generation of radical species can be responsible for the reaction rate.     

Novel animation reactions of dihydrofurano[2,3-d] pyrimidines

Although alkoxypyrimidines can be aminated to yield aminopyrimidines, monoamination of 2,4- or 4,6-chloroalkoxypyrimidines results in chlorine displacement. Preferential alkoxy displacement in such systems is unusual. We now have evidence of such a displacement in the dihydrofurano[2,3-d] pyrimidines (V). In some cases two types of products, formed by displacement of either the chlorine or alkoxy substituent, were obtained.     

Reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with cyclic amines (piperidine,morpholine, and pyrrolidine)

It was shown that the reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with piperidine in the absence of a solvent gives not only a product of replacement of the chlorine atom by a piperidino group, 3-(4-N,N-dimethylaminoanilino)-2-piperidino-1,4-naphthoquinone, but also 2-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone and 2-(4-N,N-dimethylaminoanilino-2-piperidino)-1,4-naphthoquinone. The latter compounds are the only reaction products formed in dimethyl sulfoxide. The reaction with morpholine occurs in a similar way, whereas that with pyrrolidine gives only a product of replacement of the chlorine atom by hydrogen.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1995.     

Synthesis and transformations of substituted 4,6-dimethylpyrazolo[3,4-b]pyridyl-3-azides and -sulfonyl chlorides

Diazotization of the amino group of 3-amino-4,6-dimethylpyrazolo[3,4-b]pyrimidines and subsequent replacement of the diazo group in the formed diazonium chlorides by an azide group gave the corresponding 3-azido derivatives. Their reactions with active methylene compounds have been studied. Substitution of the diazo group by a sulfo group gave the related 4,6-dimethylpyrazolo-[3,4-b]pyridyl-3-sulfonyl chlorides and sulfonylamides. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1556–1565, October, 2008.     

Synthesis of 2-aryl-6-nitro-4-(<Emphasis Type="Italic">vic</Emphasis>-triazol-1-yl)-1<Emphasis Type="Italic">H</Emphasis>-indoles from <Emphasis Type="Italic">E</Emphasis>-2,4,6-trinitrostilbenes

A method is developed for the preparation of 4-(vic-triazol-1-yl)indoles that involves replacement of the ortho-NO₂ group in E-2,4,6-trinitrostilbenes by an azido group, condensation of E-2-azido-4,6-dinitrostilbenes with acetylacetone, replacement of the second ortho-NO₂ group in the resulting stilbenes by N₃, and subsequent thermolysis of the azide into the target indole. The reactions of E-2-azido-4,6-dinitrostilbenes with cyclohexane-1,3-dione gave E-2-amino-4,6-dinitrostilbenes, which can be used for selective transformation of the ortho-NO₂ group into an amino group in E-2,4,6-trinitrostilbenes. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1293–1296, May, 2005.     

Reaction of dichloronitrobenzofuroxanes with amines and their derivatives

Reactions of 4,6-dichloro-5,7-dinitrobenzofuroxane and 4,6-dichloro-5-nitrobenzofuroxane with some aliphatic amines were studied. In the reaction of 4,6-dichloro-5,7-dinitrobenzofuroxane with 2,2-dimetoxyethylmethylamine the monosubstituted product was formed for the first time. In the reactions of 4,6-dichloro-5-nitrobenzofuroxane with amines substitution only of one chlorine atom takes place.     

Catalytic and Noncatalytic Ammonolysis of Polyfluorinated 1,3-Dichlorobenzenes

Reactions of 1,3-dichlorotetrafluorobenzene and 1,3-dichloro-2,4,6-trifluorobenzene with aqueous ammonia in the presence and in the absence of copper(I) salt lead to fluorine replacement by amino group in the para and ortho positions with respect to the chlorine atom. Ammonolysis of the resulting chloropolyfluoroanilines in the absence of a catalyst involves replacement of fluorine atom in the meta position with respect to the amino group. In the presence of copper(I) salt, catalytic aminodechlorination occurs at the para and ortho positions with respect to the amino group introduced in the first stage.     

Antimicrobial polymers containing melamine derivatives. II. Biocidal polymers derived from 2‐vinyl‐4,6‐diamino‐1,3,5‐triazine

Poly(2‐vinyl‐4,6‐diamino‐1,3,5‐triazine) (PVDAT) and a series of poly(styrene‐co‐2‐vinyl‐4,6‐diamino‐1,3,5‐triazine) (PS‐co‐VDAT) copolymers were synthesized via conventional free‐radical polymerizations. The polymer structures were confirmed by Fourier transform infrared, NMR, and elemental analysis. The molecular weights were determined by gel permeation chromatography studies, and the thermal properties were characterized by differential scanning calorimetry and thermogravimetric analysis. After treatment with chlorine bleach, PVDAT and PS‐co‐VDAT provided potent antimicrobial functions against multidrug‐resistant Gram‐negative and Gram‐positive bacteria. The antimicrobial functions were durable for longer than 3 months and rechargeable for more than 50 times. The structure–property relationship of the polymers was further discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4089–4098, 2005     

Synthesis and properties of some aryl-s-triazines

The synthesis and reactions of several substituted s-triazines were studied in attempts to prepare 4,6-bis(4-chlorophenyl)-s-lriazine-2-carboxylie acid ( 2 ) and 2-aldehyde ( 8 ). The 4,6-bis-(4-chlorophenyl)-s-triazine derivatives were surprisingly inert to a variety of reagents. 4,6-Bis-(4-chlorophenyl)-2-methyl-s-triazine ( 1 ) could not be oxidized with any of a variety of oxidants. On bromination 1 gave 4,6-bis(4-chlorophenyl)-2-dibromomethyl-s-triazine ( 4 ) which was resistant to hydrolysis but on oxidation with selenium dioxide gave 2 . Compound 2 was also prepared by the oxidation of 4,6-bis(4-chlorophenyl)-2-hydroxymethyl-s-triazme ( 7 ) with potassium permanganate. Other reagents did not oxidize 7 to 8 . 4,6-Bis(4-chloroanilino)-2-mcthyl-s-triazine ( 3 ) was also resistant to oxidizing agents. 2-Diazomethy1-4,6-dichloro-s-triazine ( 11 ) on reaction with 4-chloroaniline gave 4,6-bis(4-chloroanilino)-2-chloromethyl-s-triazine ( 12 ). All efforts to prepare 8 were unsuccessful.     

Synthesis,structure, and biologic activity of products of reactions between dinitrodichlorobenzofuroxane and aminopyrimidines in aqueous dimethyl sulfoxide

Reactions of 4,6-dinitro-5,7-dichlorobenzofuroxane with substituted pyrimidines in aqueous DMSO proceed through an intermediate formation of 5-hydroxy-4,6-dinitro-7-chlorobenzofuroxane owing to the hydrolysis of one of the chlorine atoms with the subsequent formation of pyrimidine salts exhibiting a high biologic action.     

Synthesis,crystal structures,and superoxide dismutase activity of two isostructural copper(II)–zinc(II) complexes derived from N,N′-bis(4-methoxysalicylidene)cyclohexane-1,2-diamine

Two new isostructural copper(II)–zinc(II) complexes, [CuZnLBr₂] (1) and [CuZnLCl₂] (2) (H₂L = N,N′-bis(4-methoxysalicylidene)cyclohexane-1,2-diamine), have been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Both complexes crystallize in the P-1 space group. The Cu in each complex is four-coordinate square planar with two imines and two phenolates of L. The Zn in each complex is four-coordinate tetrahedral with two phenolates of L and two halides (Br for 1 and Cl for 2). The superoxide dismutase (SOD) activity of the complexes indicates that both complexes are rudimentary models for SOD.     

Reactions of 5,7-Dichloro-4,6-dinitrobenzofuroxane and -furazane with Triphenylphosphine

Reactions of 5,7-dichloro-4,6-dinitrobenzofuroxane and 5,7-dichloro-4,6-dinitrobenzofurazane with triphenylphosphine proceed through a nucleophilic aromatic substitution of chlorine and nitro groups in the sixmembered ring of the heterocycles. The structure of the phosphorylation products was established from the IR, ³¹P NMR, and mass spectra and from XRD and elemental analysis. Schemes of the routes of the phosphorylation are discussed.