Biotransformation of pinenes XVII. Transformation of α-and β-pinenes by means of Armillariella mellea (honey fungus), a parasite of woodlands

A culture of Armillariella mellea species was adapted to carry out microbial transformations of (+), (-), and (±)-α-pinene and (-)-β-pinene . The composition of products obtained indicated that allylic hydroxylation of all substrates was the most characteristic reaction for Armillariella mellea species. The hydroxylation occurred either directly in unchanged pinane skeleton yielding among other compounds verbenol ( ) and verbenone ( ) or was preceded by a cleavage of four-membered rings in substrates to form a menthane skeleton. The latter reaction leads to allylic alcohols and diols, mainly trans-sobrerol ( ) and 7-hydroxy-α-terpineol ( ).     

The synthesis of polymers from phenylphosphonic diisocyanate and diamines

Phenylphosphonic diisocyanate has been prepared and polymers from its condensation with diamines using the interfacial technique are reported. The polymers are believed to contain the following repeating structure:      

Hapten-carrier relationships in immunological unresponsiveness

Cyclophosphamide-treated mice received 10 mg of a hapten-protein conjugate 4-Hydroxy-5-iodo-3-nitro-phenacetyl bovine serum albumin (NIP_1.1BSA) over 10 weeks. Three and seven weeks later they were challenged. The responses of the paralyzed mice relative to control mice are given below in a simplified form. We concluded that the paralysis-treatment had caused unresponsiveness to some antigenic determinants (at least NIP) but priming to others.     

Synthesis and immunological properties of an artificial antigen with the repeating oligosaccharide unit of Salmonella illinois as haptenic group

The serological specificity of Salmonellae (O-specificity) is mediated by oligosaccharide subunits (repeating units) of the species-specific cell wall polysaccharides. With S. illinois (O-specificities 3, 15 and 34 of the Kauffmann-White scheme) as a representative example, it was possible to achieve the coupling of a complete repeating unit of that kind (in the case of S. illinois a tetrasaccharide) to protein, thus converting it into an artificial antigen. The repeating tetrasaccharide of the O-specific S. illinois polysaccharide has been obtained by partial acid hydrolysis of the O-specific S. illinois lipopolysaccharide and has the following structure with rhamnose as the reducing terminal sugar: In a reaction of this tetrasaccharide (TS_ill) with o-phenylenediamine and m-nitrophenylhydrazine and its subsequent reduction, TS_ill-_illl-(3-amino-phenyl)-flavazole was prepared, which was then coupled to edestin by means of the azo-method. Antisera obtained after immunization of rabbits with the TS_ill-_illl-(3-azophenyl)-flavazole-edestin conjugate contained TS_ill-specific antibodies, as shown by agglutination of S. illinois bacteria as test antigen (titers up to 1:2500). The specificity of these antibodies was tested in detail by cross-agglutination with various bacterial strains. These antibodies are predominantly directed against the non-reducing end group Glc Gal (Man) (O-factor 34), and only to a slight extent against the internal groupings' Gal Man (O-factor 15) and Man (Rha) (O-factor 3). The serum antibodies did not show cross-reactions with O-factor 12₂, which differs from O-factor 34 in the configuration of the Gal Man-linkage (12₂ :α-glycosidic, 34:β-glycosidic). Thus, by immunization of rabbits with a TS_ill-_illl-(3-azophenyl)-flavazole edestin conjugate, a largely factor-specific (anti-34) antiserum was obtained.     

Branched and Functionalized Polybutadienes by a Facile Two‐Step Synthesis

Anionic polymerization was used to prepare silane‐endfunctionalized polybutadiene macromonomers with different molecular weights ranging from 9 000 to 34 000 g · mol^?1. These were polymerized by a hydrosilylation reaction in bulk to obtain branched polymers, using Karstedt's catalyst. Surprisingly, the addition of monofunctional silanes during the polymerization showed only a minimal effect concerning the degree of polymerization. Furthermore, it was possible to introduce a variety of functional silanes without increasing the overall number of reaction steps by a convenient AB₂ + A type “pseudocopolymerization” method. All branched polymers were analyzed by SEC, SEC‐MALLS, SEC‐viscosimetry. ¹H NMR spectroscopy, and DSC concerning their branching ratio. The branching parameters for the branched polymers exhibited similar characteristics as for hyperbranched polymers obtained from conventional AB₂ monomers. Detailed kinetic studies showed that the polymerization occurred very rapidly in comparison to the hydrosilylation polymerization of classical AB₂ type carbosilane monomers.

     

Radikalbildung und Kettenbruch bei der Radiolyse von Polypropylensulfid

Radiolysis of polypropylene sulfide with thiol and thioether endgroups was investigated. The results of change in average molecular weight with radiation dose show that statistical main chain scission takes place (G_sc = 0.4–0.7). The following radicals could be identified by ESR-spectroscopy: A mechanism is proposed, which correlates the radical formation with chain scission. It can be shown that predominantly C? C bond scission and not C? S bond scission takes place.     

The synthesis of dicarboxylie acids containing oxadiazole rings and polyamides derived from them

Novel dicarboxylic acids containing one or two 1,3,4-oxadiazole rings in a molecule were synthesized by the reaction between orthoesters and acid hydrazides These dicarboxylic acids have the following structures: and where R represents a phenylene or an alkylene group and n = 1-4. The polyamides from p-xylylenediamine with these dicarboxylic acids were also prepared. The polymers are generally insoluble in m-cresol but soluble in conc. sulfuric acid. The melting points were estimated at above 350°C. Copolyamides of high molecular weights with aliphatic polyamides were obtained.     

Studies on homologous series of oligomeric antioxidants derived from p-cresol/formaldehyde condensates. III. Evaluation in an ethylene/propylene copolymer

The effectiveness of compounds of the type as antioxidants in an ethylene/propylene (EP) copolymer has been examined and the results compared with those for some commercial high molecular weight antioxidants. Increasing the mol. wt. of the additive was found to improve its antioxidative efficiency and also to reduce the degree of interference with cure. Comparison with the results of earlier work¹ showed that the efficiency of the antioxidants was affected by the nature of the polymer substrate.     

Synthesis of some new poly(phosphonylhydrazides)

Polymers have been prepared from the condensation of phenylphosphonic diisocyanate with hydrazides using the interfacial technique. The polymers are believed to contain the following repeating structure: The reactivity of nitrogen compounds with phenylphosphonic diisocyanate is of the order amines > hydrazines ≈ hydrazides > ureas.     

Semicontinuous Emulsion Polymerization of Butyl Methacrylate and 1, 3‐Butadiene in the Presence of Cyclodextrins and Cytocompatibility of Dicarboxylic Acid Telechelic Oligo(butyl Methacrylate)s Derived from Ozonolysis of the Latexes

Ozonolysis of unsaturated polymers produced useful telechelic oligomers that can form building blocks for networks and block copolymers. The unsaturated polymers can be prepared by semicontinuous emulsion polymerization with dienes, and here it is shown that the addition of cyclodextrins enhanced the incorporation of these comonomers. Both α‐ and β‐cyclodextrin provide copolymers with higher fractions of butadiene (BD) incorporated into the chain but α‐cyclodextrin had the highest levels of incorporation. Oxidative work up after ozonolysis produced latexes of carboxylic acid oligomers of different molar masses. A clear effect of polymer size on toxicity was observed with the oligomers with < 2 700 g · mol.^?1 proving to have similar cytotoxic effects to lactic acid. However, oligomers with above 2 700 g · mol.^?1 were cytocompatible and gave similar results to a polylactide control material.

     

ADMET Polymerization as a Route to Functionalized Polycarbosilanes

It is now evident that ADMET chemistry can be employed to prepare a family of unsaturated carbosilane polymers containing a common backbone decorated with different alkoxysilane pendant groups, demonstrating the generality and potential utility of this chemistry. Four functionalized silicon containing dienes have been synthesized by nucleophilic substitution of the same parent diene monomer containing two reactive silicon‐chlorine bonds. These new α,ω‐diene monomers have been polymerized under ADMET conditions using the 2^nd generation Grubbs's ruthenium catalyst, producing polymers with useful molecular weights. Variation of the pendant group results in differing chemical and physical properties of the resulting polymers. We believe this chemistry offers much to broaden the synthetic pathways to new organosilicon polymers.

     

Acyclic Triene Metathesis Oligo‐ and Polymerization of High Oleic Sun Flower Oil

High oleic sunflower oil, a renewable raw material consisting of triglycerides with internal C?C‐double bonds, was polymerized via acyclic triene metathesis (ATMET) to highly branched and functionalized polyesters. If the Hoveyda–Grubbs second generation catalyst was used and methyl acrylate was introduced as a chain stopper, the molecular weight of the obtained polymers could be tuned by varying the ratio of the triglyceride and methyl acrylate. Using the first generation Grubbs catalyst for the polymerization of high oleic sunflower oil, no cross‐linking was observed, even without the use of a chain stopper. The resulting branched materials were characterized by GPC, ¹H and ¹³C NMR, and ESI‐MS.

     

Perfluoropolyether structures as surface modifying agents of UV-curable systems

New functionalised macromers containing perfluoropolyether (PFPE) structures and methacrylic end groups were synthesised and used as modifying additives for acrylic UV-curable systems. Their chemical structure is Rh-Rf-Rh, where and with p ≈ q. Notwithstanding their very low concentration, below 0.5 wt.-%, the fluorinated macromers cause a dramatic change of the surface properties of the films, without changing their curing conditions and their bulk properties. X-ray photoelectron spectroscopy (XPS) measurements showed that the macromers are able to concentrate selectively at the surfaces of the films, depending on their chemical structure and on the kind of substrate employed.     

UV‐Induced Modification of Conjugated Polymers Using Gaseous Organosilanes

Summary: This paper describes the use of trialkylsilanes for photoinduced patterning of electroluminescent polymers as a new field of application for this type of organosilicon compounds. Under UV irradiation, trialkylsilanes selectively saturate the vinylene groups in poly(p‐phenylenevinylene) (PPV)‐type polymers, while leaving aromatic units virtually unaffected (selective photobleaching). Spin cast films of polymer blends consisting of two or three different conjugated polymers were UV irradiated in the presence of gaseous trialkylsilane reagents (trimethylsilane and ethyldimethylsilane) to achieve multicolor patterning. Exploiting the host‐guest concept with polyfluorene (PF) derivatives as totally aromatic host matrix and PPV derivatives as guest polymers, dual‐color displays and, with constraints, three‐color LED displays were realized. Compared to previously reported reagents such as hydrazine and thiols, trialkylsilanes enable photochemical patterning under non‐toxic and odorless conditions. Possible mechanisms for the photoreaction with trialkylsilanes as well as perspectives for applications are discussed.

Electroluminescence spectra of LEDs based on the host‐guest system.     

Infrared spectroscopic study of the structural change of polymethacrylonitrile following heat-treatment and subsequent treatment with water

The infrared spectrum of polymethacrylonitrile (PMAN) exhibits noticeable change on heat-treatment up to 240°C, the color of the sample changed from yellowish at 120°C, through yellow and red, to deep red at 210°C or above. A new structure was proposed as a plausible structure for the chromophore of the heat-treated PMAN film, on the basis of comprehensive consideration of details of the spectral change in reference to the corresponding spectral change of polyacrylonitrile (PAN) and the spectra of compounds having similar structures. Subsequent treatment of the deep-red PMAN with hot water further drastically changed the infrared spectrum, and in turn the color changed from deep red to yellowish. The spectrum of the hydrolyzed product was in complete agreement with that of the copolymer of methacrylonitrile and methacrylic acid. Thus the structure was found to be from infrared spectral comparison.     

Rapid Synthesis and MALDI‐ToF Characterization of Poly(ethylene oxide) Multiarm Star Polymers

Multiarm PEO star polymers with a purely aliphatic polyether structure have been synthesized using hyperbranched polyglycerol (PG) with different molecular weights as a multifunctional initiator. Different degrees of deprotonation of the initiator were studied with respect to molecular weight control. The results show that the degree of deprotonation is a crucial parameter for the synthesis of well‐defined polymers with controlled molecular weights. Partial deprotonation of the PG hydroxyl groups (5–8%) was proven to represent an optimum for the synthesis of star polymers with molecular masses close to the theoretical values. Molecular weights of the stars ranged between 9 000 and 30 000 g · mol^?1. MALDI‐ToF spectra confirmed that the PEO arms in the star polymers possess homogeneous lengths.

     

Condensation polymerization of N-dithiocarbonyl alkoxycarbonyl-amino acids. Part. II. Condensation polymerization of N-dithiocarbonyl ethoxycarbonyl-DL-α-alanine in organic solvents

The effect of polymerization conditions on the rate of polymerization and molecular weights of resulting polymer was studied with N-dithiocarbonyl ethoxycarbonyl-DL -α-alanine. in toluenc, dioxane, nitrobenzene and methyl isobutyl ketone. In dioxane, which is a very suitable solvent to obtain high molecular weight polymers, the molecular weight of resulting polymer decreased with increasing monomer concentration. Basic substances accelerated the rate of polymerization, but decreased the molecular weight of resulting polymer. Water accelerated the rate of polymerization and the decrease of molecular weight was not so large.     

Preparation of Inclusion Complexes between Amylose and Ester‐Containing Polymers by Means of Vine‐Twining Polymerization

This paper reports the preparation of inclusion complexes of amylose with synthetic polymers by means of enzymatic polymerization of α‐D ‐glucose 1‐phosphate monomer (Glc‐1‐P). The synthetic polymers, employed as the guests, are poly(ε‐caprolactone), poly(δ‐valerolactone), and poly(ester‐ether), containing ester groups in the main chains. The formation of the inclusion complexes was carried out by the enzymatic polymerization of Glc‐1‐P catalyzed by phosphorylase in the presence of the guest polymers.

     

Synthesis of Vinylphosphonic Acid Anhydrides and their Copolymerization with Vinylphosphonic Acid

We present the synthesis and characterization of the compounds formed in a mixture of vinylphosphonic acid (VPA) and acetic anhydride used for the radical‐initiated VPA polymerization. High‐molecular‐weight PVPA with up to 109 000 g · mol⁻¹ was obtained from the polymerization of a mixture containing VPA, VPAAnh, VPADiAnh and their acetylated derivatives. Relative reactivities of these compounds were estimated. The resulting polymers were characterized by viscosimetry, light scattering and NMR measurements. The complexity of the polymer structure increases with increasing anhydride content in the reaction feed as can be concluded from the ¹H, ¹³C and ³¹P NMR spectra. This finding is in accordance with a cyclopolymerization mechanism resulting in five‐ and six‐membered anhydride rings within the polymer chain.

     

Production of organometallic polymers by the interfacial technique. XIX. Effect of leaving group in the synthesis of poly(stannylalkylenediamines)

A study has been made of the function of X and R on the interfacial synthesis of poly(stannylalkylenediamines) of the below form: Molecular weight and yield are constant as X is varied. The molecular weight of the polymer increases as the steric hindrance of R decreases. Possible reaction mechanisms are discussed.