λ -Benzyl-L-Glutamate Graft Copolymers of Cellulose and Poly[Arylene Ether Sulfone]

Macroinitiators with primary amino substituents were synthesized by one of the following techniques: a) cyanoethylation of cellulose followed by diborane reduction to produce aminopropylcellulose, 1; b) nitration, then SnCl₂ reduction of poly(arylene ether sulfone), 5, to produce poly(2-aminoarylene ether sulfone), 2; c) phthalimidation of 5 followed by hydrazinolysis to yield poly(2-aminomethylarylene ether sulfone), 3; and d) LiAlH₄ reduction of poly(cyanophenylene arylene ether) to poly(aminomethylphenylene arylene ether), 4. Heterogeneous grafting of Λ-benzyl-L-glutamate-N-carboxyanhydride, 8, to Polymer 1 resulted in a nonrandom distribution of amino acid residues; α-helical conformations were detected at low BLG-NCA/NH₂ ratios (<5 amino acids). Using molar ratios ranging from 1 to 100 of 8, relative to the amine concentration, grafting to Polymers 3 and 4 was effected in anhydrous THF at room temperature under homogeneous conditions. If reaction times between 24 and 48 h are utilized, high grafting efficiencies (>80%) are obtained. The conformation of the polypeptide chain was evaluated by NMR and infrared spectroscopy. Polypeptides grafted to Polymers 3 and 4 appeared to adopt the expected conformation for the chain length predicted, i.e., a progression from random coil (<8 amino acids) to β-pleated sheet (8–13 amino acids) to α-helix (> 13 amino acids). The benzyl ester functions on the BLG grafts are subject to direct modification with amine nucleophiles; studies with butylamine correlate reaction conditions with extent of ester vs peptide cleavage. In the presence of 1-hydroxybenzotriazole, aminolysis of the ester is favored and conversions to Λ-amides up to 75% without peptide cleavage are achieved.     

ESR Studies of λ-Irradiated Poly[3,3-bis(chloromethyl)oxetane]

Poly[3,3-bis(chloromethyl)] oxetane in vacuo, after λ-irradiation at 77°K and room temperature, showed ESR spectra consisting of a triplet (hfs of 22.0G) and a doublet (hfs of 17.8G), respectively. The triplet ESR spectrum is attributed to the -CH₂-C(CH₂Cl)-CH₂ -O- radical and the doublet ESR spectrum is attributed to the -CH₂-C(CH₂Cl)₂-CH-O- radical. The G values for formation of radicals are estimated to be 0.3 and 0.5 at 298 and 77°K, respectively.     

A Facile One-pot Synthesis of 2,5-Disubstituted Oxazoles Using Poly[styrene（iodosodiacetate）]

2,5-Disubstituted oxazoles were prepared conveniently by treatment of aromatic α-methyl ketones and nitriles with poly[styrene(iodosodiacetate)] in a one-pot manner.     

One-pot Synthesis of 2, 5-Disubstituted Oxazoles Using Poly[styrene（iodosodiacetate）]

2,5-Disubstituted oxazoles were prepared conveniently by treatment of aromatic α-methyl ketones and nitriles with poly[styrene(iodosodiacetate)] in one-pot process.     

Poly[4-diacetoxyiodo] Styrene–Promoted Thiocyanation of Aromatic Ethers,Anilines, and Indoles

Abstract

Thiocyanation of aromatic ethers, anilines, and indoles have been achieved using ammonium thiocyanate in the presence of poly[4-diacetoxyiodo] styrene (PDAIS) in CH₃CN at room temperature.

GRAPHICAL ABSTRACT     

Synthesis of Thiazolo[2,3‐c]‐s‐triazoles Using Poly[(4‐diacetoxyiodo)styrene]

Abstract

Arenecarbaldehyde‐4‐arylthiazol‐2‐ylhydrazones underwent ring closure with poly[(4‐diacetoxyiodo)styrene] (PSDIB) to 3,5‐diarylthiazolo[2,3‐c]‐s‐triazoles in dichloromethane.     

Synthesis of Bisindolylindeno[1,2-b]quinoxaline and Bisindolylindeno[3,4-b]pyrazine with Poly(N,N′-dibromo-N-ethylnaphthyl-2,7-disulfonamide)

Poly(N,N′-dibromo-N-ethylnaphthyl-2,7-disulfonamide) (PBNS) as novel reagent was synthesized. Bisindolylindeno[1,2-b]quinoxaline and bisindolylindeno[3,4-b]pyrazine derivatives were synthesized in a simple and efficient method from the three-component condensation reaction of indole, indane-1,2,3-trione, and diamine aromatic compounds by PBNS under solvent-free conditions at 80 °C in good to excellent yields, short reaction times, and a simple procedure for new derivatives.

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

Synthesis of Spiro[benzo[h]chromene-4,3′-indoles] and Spiro[benzo[f]chromene-1,3′-indoles]

Russian Journal of Organic Chemistry - New spiro heterocycles, spiro[benzo[h]chromene-4,3′-indoles] and spiro[benzo[f]chromene-1,3′-indoles], have been synthesized in 50–60% yield...     

Study of Intermacromolecular Complex Formation Between Acrylamide—Vinyl Alcohol Graft Copolymer and Poly[Methacrylic Acid]

Acrylamide‐vinyl alcohol (AAm/VA) graft copolymer was prepared and characterized. The interaction of the graft copolymer with poly‐(methacrylic acid) (PMAA) in water was studied by several experimental techniques, such as viscometry, potentiometry, conductometry, IR spectra, and transmittance measurements. PMAA was found to interact with the graft copolymer in two distinct steps. The relative complexation ability of PAAm and PVA with respect to PMAA does not change when these polymers are present as parts of a graft copolymer chain.     

Synthesis of Benzo[4,5]furo[3,2-b]thieno[2,3-d]pyridines —Derivatives of a New Heterocyclic System

Russian Journal of Organic Chemistry - Methyl 2-(bromomethyl)thiophene-3-carboxylates reacted with substituted 2-hydroxybenzonitriles to give methyl...     

Poly[styrene（iodosodiacetate）]：An Efficient Reagent for regioselective Azido—arylselenylation of Olefins

Poly[styrene(iodosodiacetate)]reacted with diaryl diselenides,followed by sodium azide,giving 1-azido-2-arylselenoalkanes regioselectively.The polymer reagent could be regenerated and reused.     

Synthesis of Poly[（3-octanoylpyrrole-2,5-diyl）-p-nitrobenzylidene] and Its Third-order Nonlinear Optical Property

Introduction Nonlinearoptical(NLO)organicpolymers havereceivedincreasingattentionbecauseoftheir excellentbehaviorandgoodprospectsforapplica- tiontohightechnologiessuchasopticalcommuni- cation,highdensityopticalstorageandall-optical informationprocess[1_4].Thepoly[heteroarylene- methines]andtheirderivativesareregardedaspo- tentiallyapplicativeNLOmaterials[5_8],buttheir solubilityandfilm-formingperformancearenot goodwhichisabottleneckproblemfortheapplica- tionofthesepolymers.Inthisstudy,anovel…     

Self－assembly of Novel Hetero[3]rotaxane, [2]Rotaxanes and [2]Catenane

One linear template 13 and one cyclophane template 15, both incorporating two electron rich 1,4‐dialkoxybenzene units and one diamide unit, have been synthesized. By utilizing donor‐acceptor interaction and/or intermolecular hydrogen bonding assembling principles, one novel hetero[3]rotazane 22·4Cl, possessing one neutral and one tetracationic ring components, has been synthesized from 13, through neutral [2]rotaxane 21 as intermediate. With 15 as template, tetracationic [2]catenane 23·4PF₆ was assembled by using donor‐acceptor interaction, but no neutral [2]rotaxane could be obtained under the typical conditions of hydrogen bonding assembling principle. The interlocked supramolecular compounds have been characterized and their spectral properties are investigated.     

Synthesis of [60] Fullerene-Podophyllotoxin Derivative

ＩｎｔｒｏｄｕｃｔｉｏｎＰｏｄｏｐｈｙｌｌｏｔｏｘｉｎ (1)ｉｓａｗｅｌｌｋｎｏｗｎｎａｔｕｒａｌｐｒｏｄｕｃｔｅｎｄｏｗｅｄｗｉｔｈｐｏｔｅｎｔａｎｔｉｎｅｏｐｌａｓｔｉｃａｃｔｉｖｉｔｙ .1Ｔｈｅｓｙｎｔｈｅ ｓｉｓａｎｄｐｒｅｐａｒａｔｉｏｎｏｆｄｉｆｆｅｒｅｎｔｔｙｐｅｓｏｆｄｅｒｉｖａｔｉｖｅｓｏｆｔｈｉｓｍｏｌｅｃｕｌｅｈａｖｅｂｅｅｎａｔｔｒａｃｔｉｎｇｍｕｃｈｉｎｔｅｒｅｓｔｏｆｂｏｔｈｏｒｇａｎ ｉｃｃｈｅｍｉｓｔｓａｎｄｍｅｄｉｃｉｎａｌｃｈｅｍｉｓｔｓ .2 Ｉｎｔｈｉｓｐａｐｅｒ …     

New Approach to Synthesis of Tetrahydroisoquino[2,1-c] [1,3]benzodiazepine

A concise and efficient synthesis of the new compounds tetrahydroisoquino [2,1-c] [1,3]benzodiazepine 5 and 7 is reported.     

Self-assembly of Novel Hetero[3]rotaxane,[2]Rotaxanes and [2]Catenane

One linear template 13 and one cyclophane template 15, both incorporating two electron rich 1,4-dialkoxybenzene units and one diamide unit, have been synthesized. By utilizing donor-acceptor interaction and/or intermolecular hydrogen bonding assembling principles, one novel hetero[3]rotaxane 22·4Cl, possessing one neutral and one tetracationic ring components, has been synthesized from 13, through neutral [2]rotaxane 21 as intermediate. With 15 as template, tetracationic [2]catenane 23·4PF6 was assembled by using donor-acceptor interaction, but no neutral [2]rotaxane could be obtained under the typical conditions of hydrogen bonding assembling principle. The interlocked supramolecular compounds have been characterized and their spectral properties are investigated.     

A convenient synthesis of 2-aryl substituted benzo[f] [1,2,4]triazolo[1,5-a]azepine derivatives

A convenient synthetic pathway to 2-aryl-5,6-dihydro-4H-benzo[f][1,2,4]triazolo[1,5-α]azepine derivatives 7 was developed. The synthesis was based on the cycloaddition of the 1,2,3,4-tetrahydronaphthalene a-acetoxy azo compounds 3 with Ar-CN in the presence of AlCl3 and the consecutive ring enlargement.     

Synthesis and Characterization of a Novel Aqueous Dispersion Poly[urethane-（disperse blue 14）-urethane] Dye

A novel polymeric dye of aqueous dispersion poly[urethane-(disperse blue 14)-urethane] was synthesized based on poly(propylene glycol) (PPG), 2, 4-tolylene diisocyanate (TDI), dimethylol propionic acid (DMPA), disperse blue 14 and triethylamine (TEA) depending on a modified acetone process. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of the polymeric dye, indicating an obvious carbonyl stretching absorption in disperse blue 14. The polymer was also characterized by the analysis of DSC, TGA, WAXD and UV-Vis spectroscopy.     

Poly[3,3-bis(azidomethyl)oxetane]–2,4-dinitro-2,4-diazapentane

Constructing phase diagrams for the mixtures of semicrystalline polymers and low molecular mass substances by DSC can meet with difficulties in the case of slow polymer crystallization. A problem of this kind is encountered for high-energy compositions poly[3,3-bis(azidomethyl)oxetane] (PBAMO)–2,4-dinitro-2,4-diazapentane (DNAP). In this study, the experimental phase diagram PBAMO–DNAP is constructed by an optical method, which makes it possible to visualize structural transformations. The kinetic studies by DSC and XRD reveal that 30–50 days of storing a homogenized PBAMO–DNAP mixture at room temperature are needed to attain stationary values of the crystallinity degree and heat of fusion. Even after that, the DSC method cannot deliver a solubility curve of DNAP in PBAMO, which is naturally generated by the optical method. This curve separates a domain of physical gels, effectively crosslinked by polymer crystallites and swollen with the plasticizer molecules, from a two-phase domain, in which the above gel reaches osmotic equilibrium with the pure plasticizer. It is also shown that the melting temperature of DNAP drops with growing the PBAMO content in the mixture, which is consistent with a decrease in the mean size of plasticizer crystals formed in polymer pores during the previous cooling.