Synthesis and Crystal Structure of a N,N,N′-tri(2-hydroxy-5-methylbenzyl)-1,2-ethanediamine

An aminophenol ligand, N,N,N′-tri(2-hydroxy-5-methylbenzyl)-1,2-ethanediamine, was prepared through the Mannich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound (C26H32N2O3, Mr = 420.54) belongs to the monoclinic system, space group P21/n with a = 8.6233(14), b = 10.2655(16), c = 26.017(4) ′, β = 95.797(2)o, V = 2291.3(6) ′3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections (Rint = 0.028) with 11691 observed ones (I > 2σ(I)).     

Synthesis of 3-chloro-N′-(2-hydroxy-6-pentadecylbenzylidene)benzothiophene-2-carbohydrazide

3-Chloro-N′-(2-hydroxy-6-pentadecylbenzylidene)benzothiophene-2-carbohydrazide has been synthesized by the reaction of 2-hydroxy-6-pentadecylbenzaldehyde with 3-chloro-1-benzothiophene-2-carboxylicacidhydrazide in the presence of glacial acetic acid in ethanol. The structure of this new compound was confirmed by elemental analysis, IR, ¹H NMR, ¹³C NMR and mass spectral analysis.     

Synthesis,spectroscopic characterization,thermal, and photostability studies of 2-(2′-hydroxy-5′-phenyl)-5-aminobenzotriazole complexes

Three Mn(II), Co(II), and Cu(II) new transition metal complexes of the fluorescence dye: 2-(2′-hydroxy-5′-phenyl)-5-aminobenzotriazole/PBT derived from o-aminophenol and m-phenylenediamine have been synthesized. The structural interpretations were confirmed from elemental analyses, magnetic susceptibility and molar conductivity, as well as from mass, IR, UV–Vis spectral studies. From the analytical, spectroscopic, and thermal data, the stoichiometry of the mentioned complexes was found to be 1:2 (metal:ligand). The molar conductance data revealed that all the metal chelates are non-electrolytes and the chloride ions exist inside the coordination sphere. The thermal stabilities of these complexes were studied by thermogravimetric (TG/DTG) and the decomposition steps of these three complexes are investigated. The kinetic parameters such as the energy of activation (E*), pre-exponential factor (A), activation entropy (ΔS*), activation enthalpy (ΔH*), and free energy of activation (ΔG*) have been reported. Photostability of phenyl benzotriazole as fluorescence dye and their metal complexes doped in polymethyl methacrylate/PMMA were exposed to UV–Vis radiation and the change in the absorption spectra was achieved at different times during irradiation period.     

Synthesis, spectral studies and complexation properties of N,N′-bis(5-bromo-salicylidene)-2-hydroxy-1,3-propanediamine (BSHP) and iron extraction with BSHP from oils

A Schiff base was synthesized by reaction of 1,3-diamino-2-propanol and 5-bromo-2-hydroxy benzaldehyde. The Schiff base N,N′-bis(5-bromo-salicylidene)-2-hydroxy-1,3-propanediamine (BSHP) was characterized by elemental analysis, ¹H NMR, ¹³C NMR, IR, UV-Vis spectral studies. The complexation of iron with BSHP was investigated spectrophotometrically. The extraction of iron from oil phase to aqueous phase was carried out with BSHP. Extraction conditions were optimized using central composite design. Optimum extraction conditions were found to be 32°C, 2 mL/g for the ratio of the volume of the Schiff base solution to the amount of oil, and 11 min for the stirring time. The method has been validated by using oil based metal standard, obtaining satisfactory results. The limit of detection (LOD) of the improved method is 0.04 μg/g. It has been applied to analysis of different oil samples. The concentrations of iron in olive, sunflower and corn oils were found to be 0.65 ± 0.02, 0.41 ± 0.01, 0.36 ± 0.03 μg/g, respectively. A simple, cheap, rapid, efficient, sensitive and accurate alternative analytical method for the iron determination in oils has been presented in this paper.     

Synthesis of 2′-deoxy-2′-fluororibo- and 2′-deoxy-2′,2′-difluororibonucleosides derived from 6-(het)aryl-7-deazapurines

A series of novel sugar-modified derivatives of cytostatic 6-hetaryl-7-deazapurine ribonucleosides (2′-deoxy-2′-fluororibo- and 2′-deoxy-2′,2-difluororibonucleosides) bearing an aryl or hetaryl group in position 6, was prepared and screened for biological activity. The fluororibo derivatives were prepared by aqueous palladium catalyzed cross-coupling reactions of the corresponding 6-chloro-7-deazapurine 2′-deoxy-2′-fluororibonucleoside 11 with (het)arylboronic acids. The key intermediate 11 was prepared by a six-step sequence from the corresponding arabinonucleoside by selective protection of 3′- and 5′-hydroxyls by acid-labile groups followed by stereoselective S_N2 fluorination and deprotection. The difluororibo-series was prepared by non-stereoselective glycosidation of 6-chloro-7-deazapurine with benzoyl-protected 2-deoxy-2,2-difluoro-d-erythro-pentofuranosyl-1-mesylate followed by cross-couplings, separation of anomers and deprotection. The title nucleosides did not show considerable cytostatic or antiviral activity.     

A linear trinuclear complex of copper(II) with N,N′-bis(2-hydroxy-5-methoxybenzelidene)-1,3-diiminopropane

The synthesis and X-ray crystal structure of a linear phenolate-bridged Cu(II) complex 1 with a Cu–Cu bond distance of 2.9260(5)?Å is reported. The complex consists of three Cu(II) ions with two molecules of the N,N′-bis(2-hydroxy-5-methoxybenzelidene)-l,3-diiminopropane ligand and two nitrate ions in such a manner that one ligand is connected with two Cu(II) ions. The complex is monoclinic, space group P2₁/n, with a?=?10.6305(5), b?=?13.0719(7), c?=?14.6336(8)?Å and β?=?102.549(1)° at 293?K, Z?=?2. The structure shows deprotonation of the phenolate oxygen to form a μ₂ bridge. The magnetic moment (1.627 BM per Cu₃ unit) at 300?K reveals that the spin doublet state is the ground state.     

Synthesis,spectroscopy and X-ray studies of [N′-(2-hydroxy-3-methoxybenzylidene)-4-methylbenzenesulfonohydrazide]uranyl(IV)

The C₃₀H₃₀N₄O₁₀S₂U complex (I) has been investigated and characterized by single crystal X-ray diffraction (CIF file CCDC no. 970349), IR and UV-Vis spectroscopic techniques. X-ray results show that the title compound crystallizes in the monoclinic system, space group P2₁/c with a = 14.8219(14), b = 11.6177(11), c = 20.0854(15) Å, β = 104.268(9)°, V = 3351.9(5) ų and Z = 4. In the title structure, the U atom has a distorted pentagonal-bipyramidal geometry with a tetradentate Schiff base ligand in the equatorial plane and oxo atoms in the axial positions. The C-S-N(H)-N linkage is non-planar, the torsion angle being ?98.7(15)° and the S atom showing a tetrahedral environment. The crystal packing occurs intra-inter molecular N-H?O and C-H?O hydrogen bonds.     

Thermal decomposition of several N,N′-bis(2-hydroxyiminoalkyl)-α,α′-dinitrones

Journal of Thermal Analysis and Calorimetry - N,N′-Bis(2-hydroxyiminoalkyl)-α,α′-dinitrones are of interest for the synthesis of 1,1′-dihydroxy-2,2′-biimidazoles....     

New Synthesis of 1-Aryl-4-(4-hydroxy-3,5-diiodo-α-methylbenzylidene)-2-phenylimidazol-5-ones

Some new 1-aryl-4-(4-hydroxy-3,5-diiodo--methylbenzylidene)-2-phenylimidazol-5-ones were prepared by treating the mixture of an analogous 5-oxazolone derivative with aromatic and substituted aromatic amines in the presence of Zeolite (Y-H) catalyst.     

Synthesis and X-ray crystal structures of N′-(2-hydroxy-5-methoxybenzylidene)-4-dimethylaminobenzohydra zide and its oxovanadium(V) complex with catalytic property

A new benzohydrazone compound N′-(2-hydroxy-5-methoxybenzylidene)-4-dimethylaminobenzohydrazide (H₂L) and its oxovanadium(V) complex [VOL(BHA)] · H₂O, where HBHA is benzohydroxamic acid, were prepared and structurally characterized by physic-chemical methods and single crystal X-ray diffraction. The benzohydrazone compound crystallizes in the monoclinic space group C2/c with a = 35.5873(12), b = 10.4628(4), c = 18.6059(6) Å, β = 109.499(1)°, V = 6530.4(4) ų, Z = 16, R ₁ = 0.0603, and wR ₂ = 0.1575. The oxovanadium(V) complex crystallizes in the triclinic space group $P\bar 1$ with a = 7.4775(4), b = 9.7837(5), c = 17.7076(8) Å, α = 99.457(2)°, β = 98.699(2)°, γ = 101.429(2)°, V = 1229.7(1) ų, Z = 2, R ₁ = 0.0431, and wR ₂ = 0.0937. X-ray structural analysis indicates that the benzohydrazone ligand L₂-coordinates to the V atom through the phenolate O, imino N, and enolic O atoms. The V atom in complex I is coordinated by one benzohydrazone ligand and one BHA ligand, as well as one oxo O atom, forming an octahedral coordination. The crystal structures of H₂L and I are stabilized by hydrogen bonds. Complex I is an effective catalyst for sulfoxidation.     

Facile Synthesis of 2-(4-Hydroxybiphenyl-3-yl)-1H-indoles from Anilines and 5′-Bromo-2′-hydroxyacetophenone

2-Arylindoles are attractive scaffolds because they are found in many pharmacologically active molecules. In this study, we describe the facile synthesis of diverse 2-(2-hydroxyphenyl)-1H-indoles from anilines and 5′-bromo-2′-hydroxyacetophenone in two steps using palladium-catalyzed indole cyclization as a key reaction. The indole cyclization was primarily controlled by the substituent properties of anilines. Suzuki-coupling reactions of 2-(5′-bromo-2′-hydroxyphenyl)-1H-indoles with arylboronic acids provided the corresponding 2-(4-hydroxybiphenyl-3-yl)-1H-indoles in moderate yield.     

Syntheses,Crystal Structures,and Antimicrobial Activities of N′-(5-Hydroxy-2-nitrobenzylidene)-4-dimethylaminobenzohydrazide Methanol Solvate and 2-Fluoro-N′-(5-hydroxy-2-nitrobenzylidene)benzohydrazide

Two new hydrazone compounds,N'-(5-hydroxy-2-nitrobenzylidene)-4-dimethyl-aminobenzohydrazide methanol solvate (1) and 2-fluoro-N'-(5-hydroxy-2-nitrobenzylidene)benzo-hydrazide (2),have been synthesized and characterized by elemental analysis,IR spectra,1H NMR,and single-crystal X-ray diffraction.Compound 1 crystallizes in the monoclinic space group P21/c with a=11.571(3),b=12.420(3),c=12.360(2) ?,β=97.495(2)°,V=1761.1(7) 3,Z=4,R=0.0735 and wR=0.1344.Compound 2 crystallizes in the triclinic space group P with a=7.551(3),b=8.254(3),c=11.365(2) ?,α=79.352(2),β=76.154(2),γ=71.624(2)°,V=648.2(4) 3,Z=2,R=0.0393 and wR=0.1008.The hydrazone molecules of the compounds display E configurations with respect to the C=N double bonds.In the crystal structure of 1,the hydrazone molecules are linked by methanol molecules through N-H…O,O-H…N and O-H…O hydrogen bonds,forming chains running along the c axis.In the crystal structure of 2,molecules are linked through N-H…O and O-H…O hydrogen bonds,forming ribbons running along the b axis.The preliminary antimicrobial activities were studied.     

Synthesis of 5-substituted-3-[(2′S,3′S)-3′-hydroxy-2′-hydroxymethyltetrahydrofuran-3′-yl]-1,2,4-oxadiazoles and their epimers

5-Phenyl-3-[(2′R,3′S)-3′-hydroxy-2′-dimethoxymethyltetrahydrofuran-3′-yl]-1,2,4-oxadiazole 10a and its epimer 11a, 5-methyl-3-[(2′R,3′S)-3′-hydroxy-2′-dimethoxymethyltetrahydrofuran-3′-yl]-1,2,4-oxadiazole 10b and its epimer 11b were synthesized from cyanohydrin benzoates 8a, 9a and cyanohydrin acetates 8b, 9b, respectively, by treatment with hydroxylamine in methanol via intramolecular transacylation and subsequent cyclization of the corresponding amidoximes. Hydrolysis and reduction of the dimethoxymethyl groups in the above compounds gave the desired compounds 12a, 13a, 12b and 13b.     

Studies on the Thioglycosides of N-Acetyl-Neuraminic Acid 8: Synthesis of S-(α-Sialyl)-(2→ 6)-β-Hexopyranosyl and -(2→ 6')-β-Lactosyl Ceramides Containing β-Thioglycosidically Linked Ceramide

ABSTRACT

Coupling of the sodium salt of S-(methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-α-galacto-2-nonulopyranosylonate)-(2→'6)-2,3,4-tri-O-acetyl-1,6-dithio-β-D-glucopyranose (5), -β-D-galactopyranose (8), or S-(methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-α-D-galacto-2-nonulopyranosylonate)-(2→'6)-O-(2,3,4-tri-O-acetyl-6-thio-β-D-galactopyranosyl)-(1→'4)-2,3,6-tri-O-acetyl-1-thio-β-D-glucopyranose (12), which were prepared from the corresponding 1-hydroxy compounds, 1, 2, and 9, via 1-chlorination, displacement with thioacetyl group, and S-deacetylation, with (2S,3R,4E)-2-azido-3-O-benzoyl-1-O-(p-toluenesulfonyl)-4-octadecene-1,3-diol (13), gave the corresponding β-thioglycosides 14, 18 and 22, respectively in good yields. The β-thioglycosides obtained were converted, via selective reduction of the azide group, condensation with octadecanoic acid, and removal of the protecting groups, into the title compounds.     

Synthesis of Two Isomeric Tetrasaccharides 0-α-L-Fucopyranosyl-(1→3) and (1→4)-0-(2-Acetamido-2-Deoxy-β-D-Glucopyranosyl)-(1→3)-0-(β-D-Galactopyranosyl)-(1→4)-D-Glucopyranose and a Related Tetrasaccharide 0-α-L-Fucopyranosyl-(1→3)-0-(2-Acetamido-2-Deoxy-β-D-Glucopyranosyl-(1→6)-0-(β-D-Galactopyranosyl)-(1→4)-D-Glucopyranose

ABSTRACT

Synthesis of three tetrasaccharides, namely, 0-α-L-fucopyranosyl-(1→3)-0-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-(1→3)-0-(β-D-galactopyranosyl)-(1→4)-β-D-glucopyranose (7), 0-α-L-fucopyranosyl-(1→4)-0-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-(1→3)-0-(β-D-galactopyranosyl)-(1→4)-D-glucopyranose (9), and 0-α-L-fucopyransoyl-(1→3)-0-(2-acetamido-2-deoxy-β-D-glucopyransoyl)-(1→6)-0-(β-D-galactopyranosyl)-(1→4)-D-glucopyranose (15) has been described. Their structures have been established by ¹³C NMR spectroscopy.     

Synthesis of the 4-Deoxy-2-Deutero-4-Fluoro Analog of Methyl O-β-D-Galactopyranosyl-(1→6)-β-D-Galactopyranoside

ABSTRACT

Methyl 4-deoxy-4-fluoro-6-O-(β-D-galactopyranosyl)-(2-²H)-β-D-galactopyranoside was prepared by the condensation of 2,3,4,6-tetra-O-benzoyl-α-D-galactopyranosyl bromide and methyl 2-O-benzoyl-3-O-benzyl-4-deoxy-4-fluoro-(2-²H)-β-D-galactopyranoside (17), followed by deprotection. The introduction of deuterium at C-2 in an intermediate methylhexopyranoside was achieved by a double inversion, brought about by oxidation of C-2 of a derivative of methyl α-D-glucopyranoside, to give the corresponding ketone, and subsequent reduction thereof with NaBD₄, to give a derivative with the D-manno configuration (8). Inversion of the configuration at C-2 of the latter was achieved by displacement with sodium benzoate of the O-trifluoromethanesulfonyl (triflyl) group in the 2-O-triflyl derivative of 8. The resulting synthon was converted, conventionally, to methyl 2-O-benzoyl-3-O-benzyl-6-O-trityl-(2-²H)-β-D-glucopyranoside. Its conversion into the 6-O-trityl derivative of 17, unsuccessful by treatment with dimethylaminosulfur trifluoride, was readily accomplished by the displacement of the triflyl group with fluoride ion contained in an ion-exchange resin.     

Abnormal Reaction of 1-(2′-Methoxybenzoyl)-1-(2′-hydroxy-5′-methoxycarbonylbenzoyl)methane Treated with Etyyl Orthoformate and Acetic Anhydride

邻羟基二苯甲酰基甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应通常是ＨＣ（ＯＥｔ）３作为酰化剂，得到３－苯甲酰基色酮。本文报道５－甲氧羰基－２－羟基苯甲酰基－（２′－甲氧苯甲酰基）甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应时，是Ａｃ２Ｏ而不是ＨＣ（ＯＥｔ）３作为酰化剂，生成３－苯甲酰基－２－甲基色酮。其结构经ＮＭＲ、ＭＳ、ＩＲ和ＥＡ证实。并对其反应机理作了讨论。     

A Facile Synthesis of an Advanced Glycosylation Endproduct 2-(2′-furoyl)-4(5)-(2′-furanyl)-1H-imidazole

Abstract: A three step synthesis of the advanced glycosylation endproduct 2-(2′-furoyl)-4(5)-(2′-furanyl)-1H-imidazole (4, FFI) has been achieved from 2-acetylfuran. The key step in the synthesis was the rearrangement of the hydrazinium bromide 3 in refluxing methanol.     

A Facile Synthesis of 5-(2′-Oxoalkyl)-2-Cyclopenten-1-Ones

In spite of the fact that a number of methods are available for the preparation of C-5-monoalkylated (simple alkyl) cyclopentenones¹, general synthetic routes leading to cyclopentenones possessing an activated side chain at C-5 remain virtually unknown². In connection with our synthetic studies on iridoids³, we have developed a convenient synthesis of the title compounds which we wish to report herein.