Reactions of 3-[N-chloroacetylamino-N-(4-nitrophenyl)]-2-formylindole with alkylamines

The reactions of 3-[N-chloracetylamino-N-(4-nitrophenyl)]-2-formylindole (1a) with 2-(N, N-dialkylamino)ethylamines afford complex condensation products 7b,c consisting of two similar but not identical diazepinoindole fragments. For the reaction of compound 1a with 3-(N,N-diethylamino)propylamine, the process occurs in a different manner, and the predominant product is 4-ethylaminopropyl-1-(4-nitrophenyl)-2-oxo-1,2,3,4,5,6-hexahydro[1,4]diazepino[6,5-b]indole hydrocloride (14). Two routes of these unexpected transformations were proposed. The structures of the synthesized products were proved by the ¹sH and ¹³C NMR, HMBC, and HSQC (direct proton-carbon correlation) spectra. Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1536–1542, August, 2007.     

Synthesis of Some Novel α-Cyanoketene-N,S-acetals Derived from Secondary Aliphatic Amines and Their Use in Pyrazole Synthesis

New α-cyanoketene-N,S-acetals 2(a–g) and β-dialkylamine-α-cyanoacrylates 3(g–i) were synthesized in good to excellent yields by the reaction of ethyl 2-cyano-3,3-bis(methylthio)acrylate 1 with secondary aliphatic amines (i.e., N-methylalkyl- and N-ethylalkylamines), and pyrrolidine, in the presence of triethylamine, under reflux in ethanol, for 1–16 h, depending on the amine used. Five N-methylalkyl amines and pyrrolidine yielded exclusively mono-substituted N,S-acetals 2(a–f) in good yields. On the other hand, N-ethylbenzylamine gave a mixture of monosubstituted products including N,S-acetal 2g in 35% yield and the unexpected product ethyl 3-[benzyl(ethyl)amino]-2-cyanoacrylate 3g in 50% yield. N-Ethylcyclohexylamine and N-ethylbutylamine did not produce N,S-acetals and gave only the unexpected products ethyl 2-cyano-3-[cyclohexyl(ethyl)amino]acrylate 3h and ethyl 3-[butyl(ethyl)amino]-2-cyanoacrylate 3i in good yields. The α-cyanoketene-N,S-acetals 2(a–f), 2j, and 2k underwent cyclization with the binucleophile hydrazine in ethanol under reflux to afford substituted pyrazoles 4(a–f), 4j, and 4k in good yields.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.]     

Synthesis and bioactivity evaluation of some novel sulfonamide derivatives

A simple and convenient method for the synthesis of biologically active sulfonamide derivatives was achieved. All the title compounds were characterized by spectral and elemental analysis. They were further screened in vitro for their abilities towards antibacterial, antifungal and antioxidant activities. The compound N,N'-(3,3′-dimethoxybiphenyl-4,4′-diyl)bis(4-fluorobenzenesulfonamide) (5b) and N-(3-(9H-carbazol-4-yloxy)-2-hydroxypropyl)-4-fluoro-N-isopropylbenzenesulfonamide (5e) exhibited good activity when compared to the standard bactericide, Chloramphenicol and fungicide, Ketoconazole respectively. The compounds (2S)-N-((2S,4S)-5-(4-Chloro-phenylsulfonamido)-4-hydroxy-1, 6-diphenylhexan-2-yl)-3-methyl-2-(2-oxotetrahydropyrim-idin-1(2H)-yl)butan-amide (4f) and (2S)-N-((2S,4S)-5-(4-fluorophenylsulfonamido)-4-hydroxy-1,6-diphenyl-hexan-2-yl)-3-methyl-2-(2-oxotetrahydropyrimidin-1(2H)-yl)bu-tana-mide (5f) exhibited good antioxidant activity when compared with standard antioxidant, Ascorbic acid.     

Synthesis,characterization, thermogravimetry,and structural study of uranium complexes derived from dibasic S-alkylated thiosemicarbazone ligands

Two pentagonal bipyramidal complexes, ethanol-(S-ethyl-N¹,N⁴-bis(3-methoxy-2-hydroxybenzaldehyde)-isothiosemicarbazide-N,N′,O,O′)-dioxidouranium(VI) (1) and ethanol-(S-ethyl-N¹-(2-hydroxyacetophenone)-N⁴-(5-bromo-2-hydroxybenzaldehyde)-isothiosemicarbazide-N,N′,O,O′)-dioxidouranium(VI) (2), have been prepared and characterized. Their structures have been determined by X-ray crystallography, and the structural parameters are discussed with those observed in related complexes. Electronic absorption, proton magnetic resonance, and FT-IR spectra have been recorded and analyzed. In both complexes, the U(VI) centers are surrounded by N₂O₂ donor ligands, two oxido groups, and one ethanol in a distorted pentagonal bipyramid. The thermal stability of the new complexes has also been determined.     

Zinc(II) complexes of 2-pyridine-derived N (4)- p -tolyl thiosemicarbazones: study of in vitro antibacterial activity

Reaction of N(4)-p-tolyl-2-formylpyridine thiosemicarbazone (H2Fo4pT), N(4)-p-tolyl-2-acetylpyridine thiosemicarbazone (H2Ac4pT), and N(4)-p-tolyl-2-benzoylpyridine thiosemicarbazone (H2Bz4pT) with ZnCl₂ gave [Zn(H2Fo4pT)Cl₂] (1), [Zn(H2Ac4pT)Cl₂] (2), and [Zn(H2Bz4pT)Cl₂] (3). In the first two complexes a tridentate N_py–N–S thiosemicarbazone binds to the zinc while in the latter N–S coordination occurs. Upon coordination the antibacterial activity against Salmonella typhimurium increases in 1 and 3.     

Nickel(II) complexes of N-(dialkylcarbamothioyl)-4-nitrobenzamide as single-source precursors for the deposition of nanostructured nickel sulfide thin films by chemical vapor deposition

Nickel(II) complexes of N-(di-alkyl-carbamothioyl)-4-nitrobenzamide (alkyl?=?ethyl or n-propyl) have been synthesized and characterized by infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, and mass spectrometry. The structures of bis[N-(diethylcarbamothioyl)-4-nitrobenzamide]nickel(II) (2a) and bis[N-(dipropylcarbamothioyl)-4-nitrobenzamide]nickel(II) (2b) have been determined by X-ray crystallography. FTIR and NMR of the nickel complexes showed the absence of the N–H proton resonance and the N–H stretch and shift of ν _C=O and ν _C=S as expected. Both complexes have been used as single-source precursors for the deposition of nickel sulfide nanostructured thin films by aerosol-assisted chemical vapor deposition. The nanostructured thin films were characterized by X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray analysis, and atomic force microscopy.     

Preparation and Properties of Novel Aromatic Polyamides from Diamines Containing 4,5-Imidazolediyl Structure

Novel aromatic polyamides were prepared from aromatic diamine containing 4,5-imidazolediyl unit, either by low temperature solution polycondensation or by direct polycondensation. Used diamines were 4,5-bis(4-aminophenyl)-2-phenylimidazole 1, 4,5-bis[4-(4-aminophenyl)]-2-(4-methylphenyl)imidazole 2 and 4,5-bis[4-(4-aminophenoxy)phenyl]-2-phenylimidazole 3. The obtained aromatic polyamides were produced with moderate to high inherent viscosity and soluble in polar aprotic solvents such as N,N-dimethylacetamide (DMAc), 1-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Thermogravimetric analysis showed those polymers were stable up to 422°C in nitrogen atmosphere. The glass transition temperature (T _g)s of the polymers derived from diamine 3 were in the range between 243 and 275°C, and these values were approximately 120–160°C lower than those analogue polyamide I series containing no phenoxy units. The properties of polyamide I series are also compared with those of analogue polymers that order of aromatic nuclei and amide linkage is reversible.     

Studies on the Fast Atom Bombardment Mass Spectrometry Fragmentation of Amino Sugars Using Synthetic Derivatives of the Trisaccharide Unit β-D-Glucopyranosyl-(1-3)-O-2-deoxy-2-amino-β-d-glucopyranosyl-(1-4)-O-d-glucopyranose

Abstract

N-Phthaloyl, N-acetyl, N-benzyl, N-acetyl-N-methyl, N,N-dimethyl, N-benzoyl, and N,N-dibenzoyl derivatives of the trisaccharide β-D-glucopyranosyl-(1-3)-O-(2-deoxy-2-amino-β-D-glucopyranosyl)-(1-4)-O-β-D-glucopyranose were synthesized and analyzed by FAB MS. The intensity ratios of the peaks resulting from cleavage of the anomeric bond of the glucosamine residue and the respective molecular ion peaks turned out to be high for the N-acyl derivatives and up to two orders of magnitude lower for the N-alkyl compounds. These results show that fragmentation at the anomeric carbon of the amino sugar may be assisted by the carbonyl group and the resulting cation is stabilized by delocalization of the positive charge.     

Nanoparticles and nanocrystals of a new bidentate nickel(II) complex of N-[ethyl(propan-2-yl)carbamothioyl]-4-nitrobenzamide: synthesis,characterization, and crystal structures

The nickel(II) complex of N-[ethyl(propan-2-yl)carbamothioyl]-4-nitrobenzamide has been synthesized and characterized by Fourier transform-infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, and mass spectrometry (atmospheric pressure chemical ionization mass spectrometry). The single-crystal X-ray structures of N-[ethyl(propan-2-yl)carbamothioyl]-4-nitrobenzamide (1) and bis[N-[ethyl(propan-2-yl)carbamothioyl]-4-nitrobenzamide]nickel(II) (2) have been determined from single-crystal X-ray diffraction data. Loss of the N–H proton resonance and the N–H stretching vibration and the shift of the ν_C=O and ν_C=S stretching vibrations confirm formation of the metal complex. These studies show that the metal complex is neutral in cis-configuration. The complex has been used as a single-source precursor for the deposition of nickel sulfide nanocrystals by thermolysis. The nickel sulfide nanocrystals were characterized by X-ray powder diffraction and transmission electron microscopy.     

OH−-induced β-elimination reactions with 1-(2-Xethyl)-4-nitrobenzene substrates in solvent mixture H2O/CH3CN and H2O/DMSO: Reactivity and mechanism

The behaviour of 1-(2-bromoethyl) 4-nitrobenzene (1), N,N,N-triethyl-2-(4-nitrophenyl)ethanaminium bromide (2) and N,N-diethyl-N-[2-(4-nitrophenyl)ethyl]octan-1-aminium bromide (3) in the OH⁻-induced elimination reactions with formation of 1-nitro-4-vinylbenzene in mixtures of DMSO/H₂O or CH₃CN/H₂O has been investigated. With all three substrates an increase in dipolar aprotic solvent content implies a limited increase of the second-order rate constant k _OH up to ≅605, and then an exponential increase is observed. The variation of activation parameters ΔH ^# and dGS ^#, measured in DMSO/H₂O mixtures, is parallel for 1 and 2. This similar behaviour of 1 and 2 with respect to variation in solvent composition is evidence that it is not possible to use this technique of solvent effect for the mechanistic diagnosis of elimination reactions.     

Polymerization of N,N-Dialkylacrylamides with Anionic Initiators Modified by Diethylzinc

Abstract

N,N-Dimethyl-, diethyl-, and dipropylacrylamides were polymerized with 1,1-bis(4′-trimethylsilylphenyl)-3-methylpentyllithium (I) in the presence and absence of diethylzinc in THF. Although the polymers produced with I in the absence of diethylzinc have rather broad molecular weight distributions, the addition of diethylzinc to the polymerization systems causes narrow molecular weight distributions of the polymers. The addition of diethylzinc also affect the stereospecificities of the polymers obtained. The poly(N,N-diethylacrylamide) produced with I/diethylzinc (molar ratio of 1/3-15) is highly syndiotactic, while the one obtained with I is isotactic. The configuration of the poly(N,N-dimethylacrylamide) is changed from isotactic to syndio and heterotactic rich by the addition of diethylzinc to the polymerization mixture. Little effect of diethylzinc is observed on the stereospecificity of the polymerization of N,N-dipropylacrylamide. The stoichiometric additive effect of Et₂Zn toward the initiator in the polymerization of DEAA suggests that the coordination of Et₂Zn aggregates with the propagating carbanionic species narrows the molecular weight distribution and controls the tacticity of the polymer.     

New Synthetic Approach to 4-N-Arylaminoazuleno[2,1-d]pyrimides

1-Cyano-2-N,N-dimethylformamidinylazulenes as new synthons directed to heterocycle-fused azulenes were obtained by the condensation of 2-amino-1-cyanoazulenes and N,N-dimethylformamide dimethyl acetal (DMFDMA). 1-Cyano-2-N,N-dimethylformamidinylazulene (2a) and 1-bromo-3-cyano-2-N,N-dimethylformamidinylazulene (2b) reacted with anilines (3a–h) to give 4-N-arylaminoazuleno-[2,1-d]pyrimidines in moderate yields. This reaction provides a new procedure for synthesis of pyrimidine-fused azulenes.     

Design and synthesis of novel organosoluble chiral poly(amide-ether-imide-urea) containing l-leucine moieties in the main chain

N,N′-(pyromellitoyl)-bis{N-[4(4-aminophenoxy)phenyl]-2-(4-methyl)p-entanamide} (5), as a novel chiral diamine, is synthesized through dehydration of l-leucine and pyromellitic dianhydride followed by the treating with thionyl chloride and subsequent reaction with 4,4′-diamino diphenylether in dry tetrahydrofuran. Several novel optically active poly(amide-ether-imide-urea)s (PAEIUs) with inherent viscosities of 0.37–0.46 dL g⁻¹ are synthesized via the polymerization of compound 5 with various diisocyanates under different catalytic conditions. The obtained PAEIUs are characterized by means of FT-IR, ¹H-NMR, elemental analysis, and specific rotation measurement techniques. The new polymers are readily soluble in polar organic solvents such as N,N-dimethyacetamide, N,N-dimethyformamide, and dimethyl sulfoxide, while the evaluation of their thermal stability by thermogravimetric analysis and differential scanning calorimetry confirmed their moderate to good thermal stability. Compared with our previous work, here, we have different functional groups in the main chain which provide novel polymers with much better solubility while maintaining reasonable thermal properties.     

Expeditious Synthesis of a Trisubstrate Analogue for α(1→3)Fucosyltransferase

Abstract

The synthesis of cyclohexyl 2-acetamido-2-deoxy-3-O-{2-O-[2-(guanosine 5′-O-phosphate)ethyl]-α-L-fucopyranosyl}-β-D-glucopyranoside (1), a potential inhibitor of α(1→3)fucosyltransferases, is described. Target compound 1 was assembled via fucosylation of cyclohexyl 2-acetamido-2-deoxy-4,6-O-isopropylidene-β-D-glucopyranoside (6) with ethyl 2-O-[2-(benzoylhydroxy)ethyl]-3,4-O-isopropylidene-1-thio-β-L-fucopyranoside (5) followed by debenzoylation, subsequent condensation of the resulting compound with 3′,4′ -di-O-benzoyl-5′ -O-(2-cyanoethyl-N,N-diisopropylphosphoramidite)-2-N-diphenylacetylguanosine (10) and deprotection.     

Reactions of 2-(4,5-dihydro-3-furyl)-1,3-diphenyl-1,3-diaza-2λ<Superscript>3</Superscript>-phospholidine and 4,5-dihydro-3-furylphosphonous diamides with nitrile imines

Reactions of 2-(4,5-dihydro-3-furyl)-1,3-diphenyl-1,3-diaza-2λ³-phospholidine (1) with nitrile imines are multistep processes involving cleavage of one P-N bond of the diazaphospholidine ring to form substituted 5-(2-chloroethyl)-4-(N,N′-diphenylethylenediamino)-1,4-dihydro-1,2,4λ⁵-diazaphosphorines 4 as final products. Analogs of phospholidine 1, namely, 4,5-dihydro-3-furylphosphonous dipiperidide and dimorpholide, react with C,N-diphenylnitrile imine with retention of both P-N bonds to give 5-(2-hydroxyethyl)-1,2,4-diazaphosphorinium chlorides. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1590–1593, July, 2005.     

Microwave-Assisted Synthesis of N,N-Dialkyl-P-Alkylphosphonamidic Anhydrides

A new rapid, efficient, solvent-free, microwave-assisted, and high-yielding method for the synthesis of N,N-dialkyl-P-alkylphosphonamidic anhydrides has been developed. The method involves the use of 4-dimethylaminopyridine and water under microwave irradiation. The reaction of N,N-dialkylaminoalkyl/phenyl phosphonochloridates 2a–h with 4-dimethylaminopyridine (DMAP) gave pyridinium salts, which were converted into N,N-dialkyl-P-alkylphosphonamidic anhydrides 4a–h.     

Vinamidinium salts of N-substituted aminoacetic acids

Formylation of N-phthaloylglycine with the POCl3-DMF system afforded N,N,N′, N′-tetramethyl-2-(N-phthaloyl)vinamidinium perchlorate (2). X-ray diffraction study showed that molecule 2 is planar and contains two equivalent nitrogen atoms in the three-carbon vinamidinium fragment. Salt 2 undergoes transamination with primary aromatic amines to give the corresponding bis-azomethines. The reactions with hydrazines produce substituted 4-aminopyrazoles. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 832–835, May, 2006.     

Synthesis, Spectral and Structural Study of N-[1-(N,N,N′,N′-Tetramethylphosphoramidoyl)- 1H-Benzimidazol-2-yl]-Propionimidic Ethyl Ether

The preparation of N-[1-(N,N,N,N-tetramethylphosphoramidoyl)-1H-benzimidazol-2-yl]-proponimidic ethyl ester 2 has been achieved by the reaction of N-(1H-benzimidazol-2-yl)-proponimidic acid ethyl ester 1 with N,N,N,N-tetramethylchlorophosphoramide. The structure of compound 2 has been determined by X-ray diffraction. The results of (¹H, ¹³C, ³¹P) NMR, IR, EI-MS spectral data are consistent with those obtained from the X-ray diffraction. The compound crystallizes in the triclinic system, following the EsZ conformation. In the crystal, there are two weak C3–H3s1 and C15–H15sO1 intermolecular hydrogen bonds.     

Synthesis,characterization, and structures of copper(I) complexes with N,N′-bis[1-(4-chlorophenyl)ethylidene]ethane-1,2-diamine and N,N′-bis[1-(4-nitrophenyl)ethylidene]ethane-1,2-diamine

Two ligands, N,N′-bis[1-(4-chlorophenyl)ethylidene]ethane-1,2-diamine (L¹ ) and N,N′-bis- [1-(4-nitrophenyl)ethylidene]ethane-1,2-diamine (L² ) and their corresponding copper(I) complexes, [Cu(L ¹)₂]ClO₄ (1) and [Cu(L ²)₂]ClO₄ (2), have been synthesized and characterized by CHN analyses, ¹H-NMR, IR, and UV–Vis spectroscopy. The crystal structures of L¹ and [Cu(L ¹)₂]ClO₄ (1) were determined from single crystal X-ray diffraction. L¹ lies across a crystallographic inversion center and the C=N is approximately coplanar with the benzene ring and adopts E configuration. The coordination polyhedron about copper(I) in 1 is best described as a distorted tetrahedron. Quasireversible redox behavior is observed for the complexes.     

Electrospray mass spectrometric studies of a potential antitumor drug and its analogous platinum(II) and platinum(IV) complexes with the ethylenediamine-N,N′-di-3-propanoato ligand and its dibutyl ester

Abstract  The electrospray mass spectrometric (ESI–MS) behavior of the complexes trans-dichloro(ethylenediamine-N,N′-di-3-propionato)platinum(IV), trans-dibromo(ethylenediamine-N,N′-di-3-propionato)platinum(IV), dichloro(ethylenediamine-N,N′-di-3-propionic acid)platinum(II), tetrachloro(O,O′-di-n-butyl-ethylenediamine-N,N′-di-3-propanoate)platinum(IV), chlorotribromo(O,O′-di-n-butyl-ethylenediamine-N,N′-di-3-propanoate)platinum(IV), and dichloro(O,O′-di-n-butyl-ethylenediamine-N,N′-di-3-propanoate)platinum(II), with the formulae trans-[PtCl₂(eddp)] (1), trans-[PtBr₂(eddp)] (2), [PtCl₂(H₂eddp)] (3), [PtCl₄(Bu₂eddp)] (4), [PtBr₃Cl(Bu₂eddp)] (5), and [PtCl₂(Bu₂eddp)]·H₂O (6), is reported. The deprotonated molecular ions or halide adducts are usually observed. ESI–MS data demonstrate the usefulness of the method for efficient characterization of metal complexes in solution. Graphical Abstract