Functionalization of highly electrophilic <Emphasis Type="Italic">N</Emphasis>-(2,2,2-trichloroethylidene)- and <Emphasis Type="Italic">N</Emphasis>-(2,2-dichloro-2-phenylethylidene) arenesulfonamides with dithiooxamide

Depending on the reactant ratio, dithiooxamide (ethanedithioamide) reacted as N-nucleophile or N,N′-binucleophile with highly electrophilic aldimines, N-(2,2,2-trichloroethylidene)- and N-(2,2-dichloro-2-phenylethylidene)arenesulfonamides, to give the corresponding mono- or bis-adducts, N-[2-polychloro-1-(arylsulfonylamino) ethyl]ethanedithioamides or N,N′-bis[2-polychloro-1-(arylsulfonylamino)ethyl]ethanedithioamides, in good yield.     

Reduction of <Emphasis Type="Italic">N</Emphasis>-(polychloroethylidene)- and <Emphasis Type="Italic">N</Emphasis>-(1-hydroxypolychloroethyl) arenesulfonamides with adamantane in the presence of superacids

N-(2,2,2-Trichloroethylidene)-, N-(2,2-dichloro-2-phenylethylidene)-, and N-(1-hydroxy-2-polychloroethyl) arenesulfonamides reacted with adamantane in carbon tetrachloride in the presence of oleum or concd. H₂SO₄-P₄O₁₀ mixture to give the corresponding N-(2-polychloroethyl)arenesulfonamides as a result of reduc-tion of the azomethine and OH group, respectively.     

C-amidoalkylation of pyrroles with <Emphasis Type="Italic">N</Emphasis>-trifluoromethylsulfonyl and <Emphasis Type="Italic">N</Emphasis>-arylsulfonyl polychloroaldehyde imines

N-(Trifluoromethylsulfonyl) and N-arylsulfonyl polychloroacetaldehyde imines reacted with pyrrole, 1-alkyl-, 1-benzyl-, and 1-(4-nitrophenyl)-substituted pyrroles, and bis-pyrroles to give the corresponding 2-[1-(sulfonylamino)polychloroethyl]-1H-pyrroles or mixtures of 2- and 3-[1-(sulfonylamino)polychloroethyl]-1H-pyrroles, depending on the nature of the Schiff base and substituent on the pyrrole nitrogen atom and reaction conditions. The first synthesis of 2,5-disubstituted NH-pyrrole by reaction of pyrrole with Schiff bases was described.     

Molecular structure of <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">o</Emphasis>-and <Emphasis Type="Italic">p</Emphasis>-hydroxybenzyl)cytisine

The molecular structures of N-(o-and p-hydroxybenzyl)cytisine were investigated by NMR spectroscopy, x-ray structure analysis, and molecular modeling. It was found that NMR resonances of the OH and aromatic protons in N-(o-hydroxybenzyl)cytisine were doubled because of the presence of two conformers in solution. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 165–168, March–April, 2008.     

Reactions of <Emphasis Type="Italic">N</Emphasis>-acetyl- and <Emphasis Type="Italic">N</Emphasis>-ethoxycarbonyl-2-(1-cycloalken-1-yl)anilines with <Emphasis Type="Italic">meta</Emphasis>-cloroperbenzoic acid

Reaction of N-ethoxycarbonyl-2-(1-cycloalken-1-yl)anilines with meta-cloroperbenzoic acid leads to the corresponding 2-[1-o-(3-chlorobenzoyl)-2-hydroxycyclopent-1-yl]anilines. 5-(2-Acetylaminophenyl)-5-oxopentanic or 6-oxohexanic acids are formed as main products in the reaction of N-acetyl-2-(1-cycloalken-1-yl)anilines with m-chloroperbenzoic acid in CH₂Cl₂. N-Acetyl-2-(1-cyclopenten-1-yl)-3,6-dimethylaniline is an exception in this series since its reaction stops at the stage of epoxide formation.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-(2-aminoethyl)- and <Emphasis Type="Italic">N</Emphasis>-(3-aminopropyl)cytisine

2-(N-cytisinyl)acetamide or 3-(N-cytisinyl)propanamide were prepared by treatment of the methyl esters of N-cytisinylacetic or 3-(N-cytisinyl)propanoic acids with aqueous NH₄OH. N-(2-Aminoethyl)-or N-(3-aminopropyl)cytisine was synthesized by reduction of the amide with (i-Bu)₂AlH.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-1-(Indanyloxymethyl) and <Emphasis Type="Italic">N</Emphasis>-1-(4-Hydroxybut-2-enyloxymethyl) Analogues of the HIV Drugs Emivirine and GCA-186

Summary. A series of Emivirine and GCA-186 analogues substituted at N-1 with indan-1-yloxymethyl (6a–6c) and indan-2-yloxymethyl (6d–6f) were synthesized by reaction of the corresponding bis(indanyloxy)methans with uracils having 5-ethyl or 5-isopropyl and 6-benzyl or 6-(3,5-dimethylbenzyl) substituents. A route to the corresponding N-1 substituted 4-hydroxybut-2-enyloxymethyl analogue was also devised. All newly synthesized compounds showed potent activity against wild-type HIV-1, the most active compound being 5-ethyl-1-(indan-1-yloxymethyl)-6-(3,5-dimethylbenzyl)uracil (6b), which was 50-fold more active than Emivirine.Present address: Chemistry Department, Faculty of Science, Tanta University, Tanta, EgyptA research center funded by The Danish National Research Foundation for studies on nucleic acid chemical biology     

Hydrogenation and conformational analysis of (1<Emphasis Type="Italic">R</Emphasis>,2<Emphasis Type="Italic">R</Emphasis>,6<Emphasis Type="Italic">S</Emphasis>)-3-methyl-6-(1-methylethenyl)cyclohex-3-ene-1,2-diol

Hydrogenation of (1R,2R,6S)-3-methyl-6-(1-methylethenyl)cyclohex-3-ene-1,2-diol was studied. Nickel chloride-sodium tetrahydridoborate system turned out to selectively reduce the double bond in the isopropenyl group. The results of conformational analysis of (1R,2R,6S)-3-methyl-6-(1-methylethenyl)cyclohex-3-ene-1,2-diol and its partly and completely hydrogenated derivatives were in a good agreement with the NMR data.     

A new group of potential antituberculotics: <Emphasis Type="Italic">N</Emphasis>-(2-pyridylmethyl)salicylamides and <Emphasis Type="Italic">N</Emphasis>-(3-pyridylmethyl)salicylamides

As a part of our systematic study of antimycobacterially active derivatives of salicylamides, a series of nineteen derivatives of N-(2-pyridylmethyl)salicylamides and N-(3-pyridylmethyl)salicylamides was synthesised. The compounds exhibited in vitro activity against Mycobacterium tuberculosis and M. avium. Their lipophilicity, R _M, was measured by thin layer chromatography on silica gel impregnated with trioctadecylsilane and the logarithm of the partition coefficient (octanol-water), logP, was calculated. Both the parameters of lipophilicity correlated. The quantitative relationship between the structure and antimycobacterial activity was calculated. Antimycobacterial activity increased with an increase in lipophilicity. The N-(2-pyridylmethyl)salicylamide derivatives were more active than the derivatives of isomeric N-(3-pyridylmethyl)salicylamides. The geometry of compounds was calculated and the calculation was verified by measuring the length of the hydrogen bond between hydroxyl and carbonyl groups on the salicylic moiety.     

Reactions of <Emphasis Type="Italic">N</Emphasis>-(2,2,2-trichloroethylidene)- and <Emphasis Type="Italic">N</Emphasis>-(2,2-dichloro-2-phenylethylidene)arenesulfonamides with biuret

N-(2,2,2-Trichloroethylidene)- and N-(2,2-dichloro-2-phenylethylidene)arenesulfonamides react with an equimolar amount of biuret to give 1-(1-arylsulfonylamino-2,2,2-trichloroethyl)- or 1-(1-arylsulfonylamino-2,2-dichloro-2-phenylethyl)biurets. The reactions with 2 equiv of N-(polychloroethylidene)arenesulfonamides involve both amino groups in the biuret molecule, yielding the corresponding 1,5-bis(1-arylsulfonylamino-2,2,2-trichloroethyl)- and 1,5-bis(1-arylsulfonylamino-2,2-dichloro-2-phenylethyl)biurets.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-(2-vinyloxyethyl)pyrazoles

Alkylation of pyrazoles with 2,2-dichloroethyl ether under conditions of phase-transfer catalysis was studied. The monoalkylation products of 3(5)-methylpyrazoles at 190–200°C undergo intramolecular cyclization to form bicyclic salts. Conditions for dehydrochlorination of N-[2-(2- chloroethoxy)ethyl]pyrazoles into N-(2-vinyloxyethyl)pyrazoles were found.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 8, 2004, pp. 1365–1367.Original Russian Text Copyright © 2004 by Attaryan, Martirosyan, Panosyan, Matsoyan.This revised version was published online in April 2005 with a corrected cover date.     

Synthesis and structure of <Emphasis Type="Italic">N</Emphasis>-(diaminomethylidene)- and <Emphasis Type="Italic">N</Emphasis>-[bis(cyclohexylamino)methylidene]trifluoromethanesulfonamides

N-Trifluoromethylsulfonyl-substituted guanidines CF₃SO₂N=C(NHR)₂ (R = H, cyclohexyl) were synthesized in nearly quantitative yield by reactions of N-sulfinyltrifluoromethanesulfonamide CF₃SO₂N=S=O with urea and of trifluoromethanesulfonamide with N,N′-dicyclohexylcarbodiimide. N-[Bis(cyclohexylamino)-methylidene]trifluoromethanesulfonamide was subjected to protonation with trifluoromethanesulfonic acid and bis(trifluoromethanesulfonyl)imide, and the structure of the resulting salts and initial N-trifluoromethylsulfonylguanidines was studied by NMR and IR spectroscopy and DFT quantum-chemical calculations.     

Regioselective Reaction of <Emphasis Type="Italic">N</Emphasis><Superscript>1</Superscript>-Benzyl-<Emphasis Type="Italic">N</Emphasis><Superscript>2</Superscript>-(4-nitrophenyl)ethanediamide and Acetylenic Esters

Summary. The regioselective reaction of N¹-benzyl-N²-(4-nitrophenyl)ethanediamide with dialkyl acetylenedicarboxylates or alkyl propiolates in the presence of triphenylphosphine leads to dialkyl 4-benzylamino-1-(4-nitrophenyl)-5-oxo-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates or alkyl 4-benzylamino-1-(4-nitrophenyl)-2-oxo-5-pyrrolidinecarboxylates in good yields.     

Cyclization of trifluoro-<Emphasis Type="Italic">N</Emphasis>-(prop-2-yn-1-yl)methanesulfonamides to <Emphasis Type="Italic">N</Emphasis>-(hydroxymethyl)-1,2,3-triazoles

Three-component heterocyclizations of trifluoro-N-(prop-2-yn-1-yl)methanesulfonamide, trifluoro-N-pheny-N-(prop-2-yn-1-yl)methanesulfonamide, and trifluoro-N,N-di(prop-2-yn-1-yl)methanesulfonamide with formaldehyde and sodium azide afforded N-{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}-, N-{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}-N-phenyl-, and N,N-bis{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}trifluoromethanesulfonamides as the major products together with minor 1-(hydroxymethyl)-1H-1,2,3-triazole isomers.     

Molecular properties of the copolymers of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-diallyl-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimethylammonium chloride and maleic acid

The hydrodynamic and conformational properties of molecules of poly(N,N-diallyl-N,N-dimethylammonium chloride) and N,N-diallyl-N,N-dimethylammonium chloride-maleic acid copolymers of different compositions in solutions with various ionic-strength and pH values, as well as of the polyelectrolyte complex based on the copolymer with dodecyl sulfate anions in chloroform, are studied. For poly(N,N-diallyl-N,N-dimethylammonium chloride) molecules in a 1 M NaCl solution, the Kuhn segment length and the hydrodynamic diameter of the chain are estimated as A = 3.9 nm and d = 0.48 nm, respectively. In acidic solutions with pH 3.5, the copolymers demonstrate behavior typical for polyelectrolytes. In an alkaline solution with pH 13, when 1 M NaCl is added to the solution of the copolymer containing 29 mol % maleic acid units, there is an antipolyelectrolyte effect that manifests itself as an increase in the intrinsic viscosity of the copolymer and in the hydrodynamic radius of its molecules. It is found that an increase in the fraction of maleic acid units in the copolymer from 12 to 42 mol % brings about a reduction in the equilibrium rigidity of its macromolecules from 4.1 to 2.2 nm. The equilibrium rigidity of polyelectrolyte-complex molecules is higher than that of initial copolymer molecules owing to steric interactions arising between the aliphatic chains of dodecyl sulfate anions. In an electric field, the molecules of the complex are oriented owing to the induced dipole moment resulting from the displacement of dodecyl sulfate anions along the chain contour.     

Chemosensors based on <Emphasis Type="Italic">N</Emphasis>-(2-aminophenyl)-<Emphasis Type="Italic">N</Emphasis>-(9-anthrylmethyl)amine: II

A series of N-(9-anthrylmethyl)arylimines was prepared by condensation of N-(2-aminophenyl)-N-(9-anthrylmethyl)amine with aromatic aldehydes. The study of the luminescent and complexing properties of compounds obtained showed that 2-{[2-(9-anthrylmethylamino)phenylimino]methyl}-1-naphthol and 1-{[2-(9- anthrylmethylamino)phenylimino]methyl}-6-bromo-2-naphthol were efficient highly selective chemosensors of cations Hg²⁺.     

Halocyclization of 2-(2-{4-[allylamino(thioxo)methyl]piperazin-1-yl}ethyl)-1<Emphasis Type="Italic">H</Emphasis>-benzo[<Emphasis Type="Italic">de</Emphasis>]isoquinoline-1,3(2<Emphasis Type="Italic">H</Emphasis>)-dione

Cyclization of 2-(2-{4-[allylamino(thioxo)methyl]piperazin-1-yl}ethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione by the action of iodine, bromine, or sulfuryl chloride gave 2-(2-{4-[4,5-dihydro-5-(halomethyl)-thiazol-2-yl]piperazin-1-yl}ethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione hydrohalides which were converted into 2-{2-[4-(5-methylthiazol-2-yl)piperazin-1-yl]ethyl}-1H-benzo[de]isoquinoline-1,3(2H)-dione.     

<Emphasis Type="Italic">Z</Emphasis>-and <Emphasis Type="Italic">E</Emphasis>-conformers of <Emphasis Type="Italic">N</Emphasis>-chloroacetylcytisine

N-Chloroacetylcytisine was synthesized by acylation of (–)-cytisine. Stable Z- and E-conformers with respect to rotational isomerism around the N-12–CO bond were found in PMR spectra at room temperature. The point at which PMR resonances of the Z- and E-conformers coalesced upon heating was measured. The transition barrier between the conformers was estimated.     

Conformational isomerization of <Emphasis Type="Italic">N</Emphasis>-(naphthalen-1-yl)-<Emphasis Type="Italic">N</Emphasis>-(phenyl(quinolin-3-yl)methyl)amide derivatives

A series of N-(naphthalen-1-yl)-N-(phenyl(quinolin-3-yl)methyl)amide derivatives were designed and synthesized as anti-Mycobacterium tuberculosis drugs. NMR spectra showed that two conformational isomers of these compounds exist in solution, which is not due to cis-trans isomerization of amide bond. We proposed that the spatial interactions between three large aromatic groups caused the conformational isomerization, which was supported by molecular modeling and X-ray diffraction.     

Synthesis and properties of <Emphasis Type="Italic">N</Emphasis>-nitro-<Emphasis Type="Italic">O</Emphasis>-(4-nitrophenyl)hydroxylamine

Salts of N-nitro-O-(4-nitrophenyl)hydroxylamine were synthesized by a new method of oxidative nitration, involving the reaction of O-(4-nitrophenyl)hydroxylamine with KNO₂ or NaNO₂ in the presence of PhI(OAc)₂ or PhIO as oxidants. When using Na¹⁵NO₂, the samples containing the nitro group labeled with the ¹⁵N isotope were obtained. Acidification of the appropriate salt gave N-nitro-O-(4-nitrophenyl)hydroxylamine. It is the first N-nitrohydroxylamine isolated in the H-form. Its thermal stability was investigated and the probable mechanism of decomposition was suggested. From a comparison of the ¹⁴N and ¹⁵N NMR spectra of N-nitro-O-(4-nitrophenyl)hydroxylamine with those of its O- and N-methylated derivatives, its equilibrium with the aci-form (N=NOOH) was inferred.