Synthesis ofN-(3-azido-2-nitroxypropyl)-,N-(2,3-diazidopropyl)-, andN-(2-azido-3-methoxypropyl)-N-alkylnitramines

N-(3-Azido-2-nitroxypropyl)-N-alkylnitramines andN-(2,3-diazidopropyl)-N-alkylnitramines were prepared by nitration and azidation ofN-alkyl-N-(2-hydroxy-3-chloropropyl)sulfamates andN-(3-azido-2-hydroxypropyl)-N-alkylsulfamates. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 206–208, January, 1999.     

Syntheses based on anabasine. Preparation and transformations of N-oxides

The oxidation of N-acetyl-and N-benzoylanabasine with the tert-butyl hydroperoxide (TBHP)— MoCl₅ system or MCPBA proceeds selectively at the nitrogen atom of the pyridine ring. The oxidation of N-methylanabasine under similar conditions gives a mixture of stereo-isomeric N-oxides at the piperidine nitrogen atom, their ratio depending on the reagent used. The oxidation of anabasine by TBHP— MoCl₅ or MCPBA is accompanied by dehydrogenation and results in anabaseine N-oxide. The reactions of anabasine and anabaseine pyridine N-oxides with acetic anhydride were investigated. The substituted 1H-3-pyridin-2-ones were prepared. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 322—328, February, 2006.     

Synthesis and some transformation ofN-allyl-N′-methoxy-andN-allyl-N′-tosyloxydiazeneN-oxides

The first representatives ofN-2-alkenyl-N′-alkoxydiazeneN-oxides andN-2-alkenyl-N′-sulphonyloxydiazeneN-oxides have been synthesized. Some reactions of the double bond in these compounds have been studied. The possibility of isomerization ofN-2-alkenyl-N′-alkoxydiazeneN-oxides toN-alk-1-enyl derivatives has been discovered. See Ref. 1 and the references therein. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2262–2265, November, 1998.     

Interaction of cellulose with amine oxide solvents

Cellulose I, mainly as ramie or as Avicel microcrystalline cellulose, has been monitored by optical microscopy and by ¹³C CPMAS NMR, over the course of its dissolution in hot N-methylmorpholine N-oxide solvent. Its interaction with the near-solvent N-ethylmorpholine N-oxide and related non-solvents has also been investigated. NMR shows that N-methylmorpholine N-oxide partly converts crystalline cellulose I into amorphous solid cellulose. The changes in chemical shift imply increased flexibility at the glycosidic bonds. In contrast, N-ethylmorpholine N-oxide converts cellulose I to cellulose III_I, without dissolution. Microscopy shows that the ramie fibres swell laterally, and at least some also shorten longitudinally, during dissolution. Model studies using methyl--d-glucopyranose show no evidence from ¹³C chemical shifts for different modes of binding with different solvents. However, N-methylmorpholine N-oxide binds more strongly to methyl--d-glucopyranose in DMSO than does N-ethylmorpholine N-oxide, whereas N-ethylmorpholine N-oxide binds better to H₂O. Also, ¹³C T ₁ values for aqueous cellobioside show increasing rotational freedom of the –CH₂OH sidechains as N-methylmorpholine N-oxide is added. Together, these observations imply the initial penetration of solvents and near-solvents between the molecular cellulose sheets. Subsequently, N-methylmorpholine N-oxide breaks H-bonds, particularly to O-6, just sufficiently to loosen individual chains and then dissolve the sheets.     

(N-methyl-N-alkoxymethylaminomethyl)dialkoxysilanes and bis[N-methyl-N-(dialkoxysilylmethyl)amino]methanes

(N-methyl-N-alkoxymethylaminomethyl)-dialkoxysilanes and bis[N-methyl-N-(dialkoxymethyl)amino]methanes were first obtained by the interaction of (N-methylaminomethyl) dialkoxy-R-silanes with chloromethyl alkyl ethers in yields of 40–67% and 10–25 %, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 382–383, February, 1995.     

An Efficient Method for the Synthesis of N-Acylsulfonamides: One-pot Sulfonylation and Acylation of Primary Arylamines under Solvent-Free Conditions

Summary. The preparation of N-acylsulfonamides is described using primary amines, arylsulfonyl chlorides and acyl chlorides. Reaction of primary aryl amines with arylsulfonyl chlorides in the presence of NaHCO₃ produced N-arylsulfonamides, which reacted in situ with benzoyl chloride furnishing the corresponding N-benzoyl-N-arylsulfonamides in 72–96% yields. Accordingly, 4-nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as acylating agents. All the reactions were carried out under solvent-free conditions at room temperature and the products were isolated after simple work-up in high yields and purity.     

Ab initio Computational Modeling of Glyphosate Analogs: Conformational Perspective

A historical perspective on the application of conformational analysis to structure-based ligand design approach is presented. The application of isodensity molecular electrostatic potential surfaces with the conformational energy surfaces (CES) have allowed us to reach pertinent conclusions for aiding synthetic and biochemical studies. Here we illustrate such an application on the modeling of the potent analogs of an important, environmentally stringent herbicidal compound glyphosate by constructing conformational energy surfaces. The systems were modeled by substituting F, Cl, and NH— OH moiety to the position of pharmacophoric nitrogen center in glyphosate structure. All the calculations were thoroughly performed with ab initio MO theory at Hartree–Fock method using 3-21G(d) basis functions. On the basis of the results, we identified the bioactive conformations for N-fluoro-glyphosate, N-chloro-glyphosate, and N-hydroxyamino-glyphosate as (−38^∘, 77^∘), (−61^∘, 111^∘), and (−167^∘, −169^∘), respectively. Geometry optimization of certain selected conformations of these compounds using hybrid DFT method with 6–31+G(d) basis functions provides nearly equal values of φ and ψ. Moreover, the results indicate that the global minimum structures of N-fluoro and N-chloro analogs of glyphosate show cyclic conformation whereas the N-hydroxyamino-glyphosate global minimum structure shows spyrocyclic and zig-zag conformation. Also, the predicted bioactive conformation of N-hydroxyamino analog optimally overlaps with glyphosate backbone in EPSPS complex with 0.1 Å RMSD value. However, the other two compounds slightly deviate from the backbone of glyphosate with RMSD of 0.92 Å for N-fluoro-glyphosate and 0.83 Å for N-chloro-glyphosate. The linear N-hydroxyamino-glyphosate exhibits relatively more number of intermolecular hydrogen bond interactions as compared to the other two analogs. Further, comparison of CES of previously studied glyphosate analogs such as N-hydroxy-glyphosate (2.2 μM) and N-amino-glyphosate (0.61 μM) with the present systems reveals the order of activity as: N-hydroxyamino-glyphosate > N-fluoro-glyphosate > N-chloro-glyphosate based on CES flexibility. Also, the calculated heats of formation of N-fluoro-glyphosate, N-chloro-glyphosate, and N-hydroxyamino-glyphosate are −288, −209, and −288 kcal/mol, respectively, which clearly indicate that the N-hydroxyamino and N-fluoro analogs of glyphosate are thermodynamically more stable than N-amino-glyphosate (−278 kcal/mol).     

Preparation ofN-nitrohydroxylamines by the substituting nitration method

N-Nitro-N-methyl-O-substituted hydroxylamines were synthesized in high yields by nitration of appropriateN-acetylhydroxylamines with nitrogen pentoxide.Translated fromIzvestiya Akademioi Nauk. Seriya Khimicheskaya, No. 3, pp767–769, March, 1996.     

The reaction of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with dihalomethanes

Methylene-bis[N′-oxydiazene-N-(β-hydroxyalkyl)N-oxides] were synthesized by the reaction of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with diahalomethanes. The effect of the nature of the starting reagents and the reaction condtions on the yields of the target compounds was studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2266–2269, November, 1998.     

N-Phosphorylated lactams

The phosphorylation ofN-trimethylsilyllactams by phosphorus(III) acid chlorides results in correspondingN-phosphinolactams in high yields. The derivatives thus obtained have been used in the synthesis ofN-phosphoryl- andN-thiophosphoryllactams. The reversibility of the reaction of phosphinolactams has been established.For communication 1 see Ref. 1.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2250–2255, November, 1995.     

Synthesis ofN-3-chloroalkoxy-2-nitroxypropyl-N-alkylnitramines and their subsequent azidation

Nitration ofN-3-chloroalkoxy-2-hydroxypropyl-N-alkylsulfamates gave the correspondingN-3-chloroalkoxy-2-nitroxypropyl-N-alkylnitramines. Azidation of the latter resulted inN-azido-3-azidoalkoxypropyl-N-alkylnitramines. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 673–676, April, 1998.     

正辛烷为稀释剂不对称N-甲基-N-辛基烷基酰胺萃取铀(Ⅵ)的研究(英)

The extraction of uranyl nitrate was studied with newly synthesized unsymmetrical alkylamides, Nmethyl-N-octyloctylamide (MOOA), N-methyl-N-octyldecanamide (MODA), and N-methyl-N-octyldodecanamide (MODOA), employing n-octane as diluent. The effect of the concentrations of nitric acid, sodium nitrate and extractants on the extraction was investigated and the extraction mechanism was suggested. The effect of temperature on the extraction was also studied and the related thermodynamic functions were calculated. The extracted species were characterized by FTIR spectrometry。     

Preparation ofN-nitrohydroxylamines by substitutive nitration

Interaction of Na- or K-salts ofN-acetyl-N-methylhydroxylamines with aryl or aryl halides results in correspondingO-substitutedN-acetyl-N-methylhydroxylamines. Nitration of these compounds by nitronium salts or dinitrogen pentoxide results inO-substitutedN-methyl-N-nitrohydroxylamines.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 239–241, January, 1996.     

Geminal systems. 50. Synthesis and alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas,carbamates, and benzamides

Procedures were developed for the synthesis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and benzamides by the reactions of the corresponding N-alkoxy-N-chloro derivatives with sodium carboxylates in MeCN. N-Chloro-N-ethoxy-p-toluenesulfonamide was inert in this reaction. Alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and tert-alkylamines afforded the corresponding N,N-dialkoxy derivatives, whereas alcoholysis of N-acetoxy-N-ethoxybenzamide gave rise to alkyl benzoates.     

Synthesis and structure of di(NON-azoxy)formals and some relatedN-alkyl-N′-alkoxydiazeneN-oxides

A series of di(NON-azoxy)formals and some relatedN-alkyl-N′-alkoxydiazeneN-oxides were prepared by the reaction ofN-nitrosohydroxylamine salts with dihaloalkanes. The dependence of the yield of di(methyl-NON-azoxy)formal on the reaction conditions and the nature of the cation was studied. The structure of di(methyl-NON-azoxy)formal and di(phenyl-NON-azoxy) formal as well as of the coppertert-butylnitrosohydroxylaminate was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1486–1493, August, 1997.     

Reactions of functionalized alkyl halides withN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxide salts

Some characteristic features of reactions ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxide salts with various α- and β-functionalized alkyl halides were established. Some α-and β-functionalizedN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides and e ethylenebis[N-(β-hydroxyalkyl)-N′-oxydiazeneN-oxides] were synthesized for the first time. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 123–129, January, 1999.     

Natural monocrystalline chalcopyrite and galena as electrochemical sensors in non-aqueous solvents. Part II: potentiometric titrations of weak acids in N,N-dimethyformamide and N-methylpyrrolidone

Natural monocrystalline chalcopyrite and galena as new indicator electrodes for the potentiometric titration of weak acids in N,N-dimethylformamide and N-methylpyrrolidone were used. The investigated electrodes showed a linear dynamic response for p-toluenesulfonic acid concentrations in the range from 0.1 to 0.001 M, with a Nernstian slope of 59.0 mV for chalcopyrite and 33 mV per decade for galena in N,N-dimethylformamide, 56.1 mV for chalcopyrite, and 32.0 mV per decade for galena in N-methylpyrrolidone. The potential in the course of the titration and at the titration end point was rapidly established. Sodium methylate, potassium hydroxide, and tetrabutylammonium hydroxide proved to be very suitable titrating agents for these titrations. The response time was less than 10–11 s, and the lifetime of the electrodes is limitless. The advantages of the electrodes are log-term stability, fast response, reproducibility, easy preparation, and low cost. The results obtained in the determination of the investigated weak acids deviated on average by ±0.04–0.34% from those obtained with a glass electrode.     

Synthesis of 3-alkoxy-2-nitroxypropyl-N-alkylnitramines

It was shown that 3-alkoxy-2-nitroxypropyl-N-alkylnitramines can be prepared by nitration of the corresponding 3-alkoxy-2-hydroxypropyl-N-alkylsulfamates. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1987–1989, November, 1997.     

Synthesis of new functionally substituted fullerenopyrrolidines

New fullerenopyrrolidines were synthesized by the three-component reactions of fullerene C₆₀, N-methylglycine, and aromatic aldehydes, viz., N,N-bis(2-chloroethyl)-4-aminobenzaldehyde, N-(2-chloroethyl)-N-methyl-4-aminobenzaldehyde, indole-3-carbaldehyde, 4-phenylbenzaldehyde, and anthracene-9-carbaldehyde. The structures of the resulting compounds were established by spectroscopic methods.     

Nitropyrazoles

A number of substitutedN-nitropyrazoles were prepared by direct nitration of substituted pyrazoles. The dependence of the direction of nitration on the reaction conditions was studied. For Part 9, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1198–1201, June, 1997.