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Commercially produced maize starches were treated with protease (Promod 25P) and their composition and properties were compared with untreated controls. It was found that, although protease treatment reduced the starch protein contents by 41%, 21% and 37% for the waxy, normal and amylomaize starches, respectively, it also caused some pits on the granule surfaces, which were evident by scanning electron microscopy (SEM), but no obvious decrease in granule dimensions (Coulter Counter Multisizer). The protein extraction was associated with decreases in starch lipid content by 42%, 40% and 45% (waxy, normal and amylomaize starches, respectively) and a decrease in total amylose content (30.7-26.0%) for the normal maize starch. The gelatinisation parameters of the starches by differential scanning calorimetry (DSC) in water, 0.001M HCl or NaOH were less obviously affected by protease treatment in common with the swelling factors at 80°C. The amount of α-glucan leached by the swollen (80°C) granules was, however, increased by the protease treatment by factors of 3.8, 1.4, and 1.1, for the waxy, normal and amylomaize starches, respectively. Although proteases provide a useful tool for the purification of native starches, commercial protease preparations need to be controlled in terms of amylase content to prevent modifications to starch structure and properties during industrial processing.

A method was developed to produce pure maize starch from maize flour using a protease processing step, and additional salt washing and sulphite steeping steps. A range of commercial protease enzymes were evaluated for this purpose. The laboratory scale procedure that was developed, using one protease in particular (Promod P25P, thermolysin), produced relatively pure starch (

The synthesis of a set of novel homochiral bis-imine ligands 4 derived from d -isomannide 6 , and their application in the Cu 2+ -catalyzed asymmetric Diels–Alder reaction of cyclopentadiene and N - tert -crotonoyloxazolidinone 1 is reported.

We have investigated several 1,3-dipolar cycloadditions of a chiral nitrone prepared from L-erythrulose. While cycloadditions to carbon-carbon multiple bonds of dipolarophiles such as ethyl acrylate, ethyl propiolate, or dimethyl acetylenedicarboxylate were poorly stereoselective, reaction with acrylonitrile provided predominantly one diastereomeric adduct. Furthermore, the regioselectivity exhibited by the two structurally similar dipolarophiles ethyl acrylate and ethyl propiolate was found to be opposite. The molecular mechanisms of these cycloadditions have thus been investigated by means of density functional theory (DFT) methods with the B3LYP functional and the 6-31G and 6-31+G basis sets. A simplified achiral version of nitrone 1 as the dipole, and methyl propiolate or acrylonitrile as the dipolarophiles, were chosen as computational models. The cycloadditions have been shown to take place through one-step pathways in which the C-C and C-O sigma bonds are formed in a nonsynchronous way. For the reaction with methyl propiolate, DFT calculations predict the experimentally observed meta regioselectivity. For the reaction with acrylonitrile, however, the predicted regioselectivity has been found to depend on the computational level used. The calculations further indicate the exo approach to be energetically favored in the case of the latter dipolarophile, in agreement with experimental findings. The main reason for this is the steric repulsion between the nitrile function and one of the methyl groups on the nitrone that progressively develops in the alternative endo approach.

An efficient and reproducible procedure for the preparation of 1-O-silylated derivatives of several 3,4-O-acetals of erythrulose from the parent sugar is described.

D(−)-Lactic acid was produced by Lactobacillus delbrueckii DSM 20072 (ATCC 9649) (LD), L(+)-lactic acid by Lactobacillus casei subsp. rhamnosus DSM 20021 (ATCC 7469) (LC) and by Lactobacillus salivarius subsp. salivarius DSM 20492 (ATCC 11742) (LS) on MRS medium and glucose substrate homofermentatively in batch cultures. LS exhibited the highest specific growth rate (μ = 1·41 h−1) and the highest specific productivity (π = 5·45 h−1). Acetate and citrate stimulated its growth. Substrate inhibition occurred at 30 g litre−1 glucose for LD, 26 g litre−1 glucose fo LC, and no inhibition was observed up to 100 g litre−1 glucose for LS. 60 g litre−1 lactate solution at pH 6 caused only slight product inhibition of LS. The product was extracted by four different amine carriers (Amberlite LA2, Hoe F2562, Hostarex A327 and Alamin 366) in the presence of modifiers (long-chain alcohols, alkylphosphates and acidic organic compounds) in kerosene and butylacetate, and a phosphinoxide (Cyanex 923). When using Hostarex A327 in oleylic alcohol or Cyanex 923 (phosphinoxide carrier) in kerosene or in oleylic alcohol, no modifier was necessary. The extent of lactic acid extraction was evaluated and the separation of lactic acid from citric and acetic acids was investigated. The re-extraction of the free acid under different conditions was not very successful. A maximum lactic acid yield of 72% was obtained. Except for kerosene and oleyl alcohol, the biocompatibility of the other chemicals was unsatisfactory. Their application for in situ extraction cannot be recommended. Recovery of the free lactic acid by electrodialysis and bipolar membrane is very promising. In situ recovery is possible.

Recent developments in the formulation of detergents have been driven by a strong consumer demand for natural and biodegradable products. Detergent manufacturers responded to this demand with corresponding products and advertising slogans such as “fully biodegradable”, “natural” or even “double natural” to oust their competitors. In a detergent formulation, starch- derived products can in principle be used for the following purposes: as the hydrophilic head group in surfactants, as the starting material for (poly)carboxylate co-builders and as the backbone of bleaching activators. Non-ionic classical surfactants can be replaced by alkylpolyglucosides (APGs), a class of products completely based on renewable resources such as glucose and fatty alcohols derived from natural fatty acids. Sodium tripolyphosphate (STPP), the product responsible for the eutrophication of surface waters, can be substituted by a combination of an inorganic zeolite and highly oxidised starch (dicarboxylic starch) or by citrate. Acetylated polyols derived from hydrogenated carbohydrates such as sorbitol can take over the function of the petrochemically-based tetraacetyl ethylene diamine (TAED) used as activator to allow perborate bleaching at lower washing temperatures.

Methylation analysis, enzymic digestion, n.m.r. spectroscopy, and Smith degradation showed that the major extracellular polysaccharide, isolated from cultures of the fungus Glomerella cingulata, was a (1----3)-beta-D-glucan with side chains of 1-4 (1----3)-linked beta-D-glucose residues attached to position 6. A (1----6)-beta-D-glucan was produced by the fungus in small proportions. Treatment of the (1----3,1----6)-beta-D-glucan (890,315) with greater than 0.05M NaOH at greater than 150 degrees, or Me2SO-H2O with a concentration of dimethyl sulfoxide of greater than 80%, irreversibly destroyed the highly ordered structure responsible for the high viscosity of aqueous solutions. The strong shift of the lambda max of aqueous solutions of Congo Red by the degraded glucan, the fact that the mol. wt. of the original glucan was approximately 4 times higher than that of the degraded polymer, and the suppression of the n.m.r. signals for C-3 indicated that the original glucan had a highly ordered structure, probably built up from single helices.

The increasing garbage mountain is more and more recognized as an ecological threat. Space for landfills is limited and additional incineration capacities require high capital investments and pose additional envrironmental problems. In the FRG from total annual 14 million t of household waste, 700,000 t are non-degradable plastic materials (polyolefines, polystyrene and polyvinylchloride), especially for packaging. Different strategies are being followed to reduce the 5% plastics in household waste: prevention, recycling, chemical valorization, thermic utilization (incineration) and use of degradable polymers. The latter are reviewed in detail: chemical modification of classical polymers into photo- and chemo-degradable materials, physical mixing of 6–20% granular starch with polyethylene or polypropylene, coprocessing of more than 50% disintegrated starch with hydrophilic polymers like polyacrylate or polyvinylalcohol to biodegradable films for agricultural mulch or carrying bags, thermoplastic extruded starch with plasticiser containing more than 90% starch for blister packaging and disposables for fast food and finally biodegradable polyesters like poly-hydroxybutyric acid (PHB) and polylactic acid, produced by fermentation processes. Die Funktion der Starke in biologisch abbaubaren thermoplastischen Materialien. Der wachsende Mullberg wird mehr und mehr als okologische Bedrohung angesehen. Platz fur Deponien ist begrenzt, zusatzliche Verbrennungsanlagen erfordern hohe Investitionen und ergeben zusatzliche Umweltprobleme. In der Bundesrepublik Deutschland werden jahrlich 14 Millionen t Haushaltsabfall erzeugt, mit einem Anteil von 700 000 t nicht abbaubarer Kunststoffe (Polyolefine, Polystyrol und Polyvinylchlorid), insbesondere Verpackungsmaterialien. Verschiedene Entsorgungskonzepte werden verfolgt um den 5%-Anteil an Kunststoffen im Hausmull zu verringern: Abfallvermeidung, Recycling, chemische Verwertung, thermische Verwertung (Verbrennung) und der Gebrauch abbaubarer Polymerer. Letztere werden eingehend besprochen: chemische Modifizierung klassischer Polymerer zu photolytisch- und chemisch abbaubaren Materialien, physikalisches Mischen von 6–20% granularer Starke mit Polyethylen oder Polypropylen, Verarbeiten von mehr als 50% desintegrierter Starke mit hydrophilen Polymeren wie Polyacrylat oder Polyvinylalkohol zu biologisch abbaubaren Folien fur die Landwirtschaft oder fur Tragetaschen, thermoplastisch extrudierte Starke mit mehr als 90% Starke fur Klarsichtverpackungen und Wegwerfartikel im Fast Food-Bereich und schlieslich biologisch abbaubare Polyester wie Polyhydroxybuttersaure (PHB) und Polymilchsaure, die fermentativ hergestellt werden.

The unnatural keto-sugar L-ribulose, presently more readily available, is an interesting “chiral pool” product. Some key-intermediates for its transformation are described.

The acetonides 2 and 4, obtained from erythritol, are excellent substrates for SAM II lipase. The resulting homochiral mono-esters 3 and 5 are suitable chiral building blocks.

Hexamethylentetramin-[Hexa]-Proben verschiedener Herkunft — Hexa DAB 7 (Fa. Merck), Hexa pro anal. (Fa. Merck), Hexa (Eigenpraparat), Hexa (unbekannter Herkunft) — wurden mit GC- und GC/MS-Analyse auf die Gegenwart fluchtiger organischer Verbindungen untersucht. Formaldehyd, Aceton, Methylamin, Trimethylamin-N-oxid und Chloroform konnten gaschromatographisch nachgewiesen und teilweise durch GC/MS-Analyse abgesichert werden. Sekundare und tertiare aliphatische Amine waren in keiner der Hexa-Proben zugegen.

The hydrochlorides from tetracycline and six tetracycline derivatives *-7-dimethylamino-6-des-methyl-6-desoxytetracycline [minocycline], 7-chlorotetracycline [chlorotetracycline], 7-chloro-anhy-drotetracycline [anhydrochlorotetracycline, 7-chloro-6-desmethyltetracycline [demethylchlorotetra- cycline], 5-hydroxytetracycline [oxytetracycline] and 6-desoxy-5-hydroxytetracycline [doxycycline] - were reacted with different amounts of sodium nitrite at 37 °C for two hours in aqueous buffer solutions at pH 2 and 4. Dimethylnitrosamine formation was confirmed by gas-liquid chromatography and by combined gas-liquid chromatography/mass-spectrometry from minocycline, doxycycline, oxytetracycline and an- hydrochlorotetracycline. Dimethylnitrosamine formation from minocycline and doxycycline was blocked by ascorbic acid. The catalytic effect of sodium thiocyanate for the dimethylnitrosamine formation from minocycline and nitrite was investigated. The different reactivity of the investigated tetracycline derivatives towards nitrite in acidic solutions is discussed by stereochemical considerations in connection with the formation of hydrogen bridge linkages. This hypothesis was confirmed by dimethylnitrosamine formation from anhydro-chlorotetracycline and sodium nitrite at pH 2.

The industrial (non-food) use of starch and starch-based products as renewable raw materials is discussed together with examples, in the following application areas: –Starch as auxiliary raw material: binder, adhesive, thickener, protective colloid. –Starch as raw material for new products in chemical or biotechnical processes: polyols, acids, polysaccharides, enzymes. –Starch as filler with specific functionality for synthetic polymers to improve application properties in e. g. polyethylene, polypropylene, polystyrene, polyurethane-foams, styrene/butadiene copolymers, polyvinylchloride. –Starch as reactive component to be incorporated during production of synthetic polymers leading to synergistic effects: urea/formaldehyde resins, phenolic resins, alkyd- and melamine resins. –Starch-based active materials which either exhibit direct functionality themselves, (e. g. as surfactants, sequestrants and bleaching boosters) or which represent building blocks for the synthesis of chiral compounds for the pharmaceutical or the agro-industries.

Thirteen N-(1-deoxy- d -fructos-1-yl)-N-nitroso- l -amino acids were prepared, in 83–95% yield, by nitrosation of the corresponding “fructose-amino acids” with sodium nitrite in water-hydrochloric acid, at pH 3. The 1H-n.m.r. spectra were complicated by the presence of different sugar-ring forms (α,β-furanoses and-pyranoses). In addition, signal doubling for all proton resonances were observed for the E/Z isomer N-nitroso compounds. Signals of β- d -pyranoses unequivocally can be assigned as >50% in solution equilibrium. In D2O, some compounds showed a slow H-D-exchange for H-1a and H-1b. Ring conformation for all E/Z isomer β-pyranoses was 2C5( d ). The 13C-n.m.r.-spectra exhibited resonances of all four ring-forms, with signal doubling for E/Z isomers, all of which could be assigned. Signals of open chain-forms were not present. For the β- d -pyranose forms, changes of chemical shifts, caused by N-nitrosation, were calculated by comparison with the educts (Δδ values) and separately discussed for E- and Z-isomers. The separation by reversed-phase, ion-pairing, l.c., and the pKa values of the nitroso derivatives are reported, as well as the e.i.-mass spectra of their per(trimethylsilyl) derivatives.

Analysis of N-nitroso compounds. II. Separation and quantitative determination of N-nitroso-N-alkylureas and N-nitroso-N-alkylurethans by high-speed high-pressure liquid chromatography . Physical data, elementary analysis data and IR, UV, NMR and mass spectra have been determined for N-nitroso-N-alkylureas and N-nitroso-N-alkylurethans. The fragmentation patterns in the mass spectrometer induced by electron impact are discussed. A fast separation is described of model mixtures of alkyl homologous N-nitroso-N-alkylureas and N-nitroso-N-alkylurethans by reversed-phase liquid—liquid distribution in a liquid chromatograph. Detection is carried out by UV absorption at 254 nm. Calibration curves for the quantitative determination of separated N-nitroso-N-alkylureas are given. The lowest detection limit for N-nitroso-N-methylurea was 10 ng.

The N -nitroso derivatives of d -fructose- l -glycine, d -fructose- l -alanine, d -fructose- l -phenylalanine, d -fructose- l -serine, d -fructose- l -aspartic acid and d -fructose- l -tryptophan (a mixture of α- N -nitroso- d -fructose- l -tryptophan and ‘indolyl-nitrosamine’- d -fructose- l -tryptophan) were tested for mutagenicity in five auxotrophic strains of Salmonella typhimurium with and without metabolic activation (S-9 mix). The alanine, phenylalanine and aspartic acid compounds were not mutagenic. The glycine and serine compounds showed a very low but reproducible increase in the numbers of his + revertants in strain TA1535 without S-9 mix. The mixture containing both nitrosated d -fructose- l -tryptophan compounds was mutagenic in all five strains, with or without metabolic activation. The α- N -nitroso- d -fructose- l -tryptophan component of the mixture, which is nitrosated at the amino group, was isolated and tested without S-9 mix. It was mutagenic in three strains. Unnitrosated d -fructose- l -amino acids, d -fructose, and the individual l -amino acids were non-mutagenic when tested under those conditions for which a positive response had been obtained with the corresponding nitrosated compounds. These results indicate the potential value of developing analytical methods to identify α- N -nitroso- d -fructose- l -tryptophan in food or food extracts that are to be screened for mutagenic components.

Analysis of N-nitroso compounds. V. Trace analysis of N-nitrosoamino acids: Gas chromatography and spectroscopy of N-nitrosoamino acid methyl esters N-Nitrosoamino acids (N-NO-sarcosine, N-NO- l -proline, N-NO-4-OH- l -proline and N-NO- d,l -piperidine-2-carboxylic acid) were reacted with methanol-H+ or diazomethane to the corresponding methyl esters in preparative and analytical scale. N-NO-4-OH- l -proline methyl ester was reacted with N-methyl-N-trimethylsilyl-trifluoroacetamide to give N-NO-4-O-trimethylsilyl- l -proline methyl ester in quantitative yield. The N-nitrosoamino acid methyl esters were characterized by physical (b.p., m.p., RF values) and spectral data (infrared, mass spectrometry, 1H nuclear magnetic resonance (NMR), 13C NMR). The fragmentations of N-NO-sarcosine methyl ester, N-NO- l -proline methyl ester and N-NO- d,l -piperidine-2-carboxylic acid methyl ester induced by electron impact in the mass spectrometer, were studied by high-resolution measurements, metastabile ions, DADI-technique and defocusing method. The ratios of E- and Z-isomers of N-nitrosoamino acid methyl esters in solution are determined by 1H NMR spectroscopy. The resonances of the methyl ester protons appear as two singlets. This is explained by interaction of the N-NO-groups with the methyl ester protons via cyclic arrangements in equilibria of E- and Z-isomers and confirmed by the 1H NMR spectrum of N-NO-sarcosine-trideuteromethyl ester. The N-nitrosoamino acids are quantitatively converted to the corresponding N-nitrosoamino acid methyl esters by reacting with diazomethane. These derivatives of N-nitroso-amino acids (including N-NO-4-O-trimethylsilyl- l -proline methyl ester) can be separated by gas-liquid chromatography on OV-17 as stationary phase. This derivatization procedure allows separation and quantitative determination of N-nitrosoamino acids by gas-liquid chromatography and confirmation by gas-liquid chromatographic-mass spectrometric analysis in nanogram amounts.

Substituted p-benzoquinones (= quinones) and substituted hydroquinones [bis-trimethylsilyl- ethers or bis-trifluoroacetates] can be separated by gas-liquid chromatography using 50 meter long thinfilm capillaries (inner diameter: 0.25 mm) coated with silicone OV 17 (50% phenyl, methyl) or silicone DC 550 (25% phenyl, methyl). Total retention times of various derivatives of p-benzoquinone and hydroquinone were deter­mined. Complex model mixtures of these derivatives can be separated by gas-liquid chromatography with temperature programs and the individual components can be clearly identified by their mass spectra in the sub microgram range by using combined gas-liquid chromatography/mass-spectrometry. This microanalytical technique was applied to identify the defensive secretion components from members of the diplopod order Julida (Arthropods). Julus nitidus produces a defensive secretion that consists exclusively of 2-methyl-3-methoxyquinone. The expelled defensive secretions of Unciger foetidus, Cylindroiulus coeruleocinctus (Iondinensis), Cylindroiulus punctatus, Cylindroiulus luridus and Ophyiulus psilosus consist of a 2-methylquinone and 2-methyl-3-methoxyquinone mixture. The presence of the corresponding hydroquinones-2-methyl-hydroquinone and 2-methyl-3-methoxyhydroquinone-was also determined in all cases.

Durch Umsetzung von 1,3,4,6-Tetra-O-acetyl-β-D-glucosamin-hydrochlorid (1) oder 1,3,4,6-Tetra-O-acetyl-β-D-galactosamin-hydrochlorid (10) mit Bromcarbonsaure-methylestern in siedendem Aceton in Gegenwart von Natriumhydrogencarbonat als Base werden die N-(1,3,4,6-Tetra-O-acetyl-2-desoxy-β-D-glucopyranos-2-yl)aminosaure-methylester 2–5 und -β-D-galactopyranos-2-yl)aminosaure-methylester 11–12 erhalten. Nitrosierung der Zuckeraminosaure-Derivate mit Distickstofftrioxid in Chloroform bei 0°C fuhrt zu den N-Nitroso-Zuckeraminosaure-Derivate 6–9 und 13–14. Synthesis of Protected N-Nitroso Sugar Amino Acids. — N-(1,3,4,6-Tetra-O-acetyl-2-deoxy-β-D-glucopyranos-2-yl) Amino Acid Methyl Esters and -β-D-galactopyranos-2-yl) Amino Acid Methyl Esters and Their N-Nitroso Derivatives Reacting 1,3,4,6-tetra-O-acetyl-β-D-glucosamine hydrochloride (1) or 1,3,4,6-tetra-O-acetyl-β-D-galactosamine hydrochloride (10) with methyl bromocarboxylates in refluxing acetone in the presence of sodium hydrogen carbonate results in the formation of N-(1,3,4,6-tetra-O-acetyl-2-deoxy-β-D-glucopyranos-2-yl) amino acid methyl esters 2–5 and -β-D-galactopyranos-2-yl) amino acid methyl esters 11–12. Nitrosation of these derivatives of sugar amino acids with dinitrogen trioxide in chloroform at 0°C leads to the derivatives of N-nitroso sugar amino acids 6–9 and 13–14.

2,2-Dimethyl-1,3-dioxolane-4-carboxylic acid derived chiral building blocks were prepared from substituted α,β-unsaturated acids with high enantiomeric purities by enzymatic hydrolysis of their n.butyl esters.

Drei Modell-Gemisched-Glucose/dl-Alanin,d-Glucose/l-Lysin undd-Glucose/l-Glutaminsaure wurden unter Zugabe von Natriumnitrit unter Maillard-Bedingungen gebraunt. Die Zugabe von Natriumnitrit erfolgte vor und nach der Braunung. Im letzteren Fall schlos sich eine kurze Nachbraunung an. Die Reaktionsbedingungen — pH-Wert und Braunungstemperaturen — wurden variiert. Die Analyse der alkalibestandigen wasserdampffluchtigen Maillard-Produkte erfolgte durch GC und GC/MS-Analyse. Bei den identifizierten Produkten handelt es sich um alkylierte Pyrazine, Furan- und Pyridin-Derivate. Nitrosopiperidin wurde aus dem Braunungsansatzd-Glucose/l-Lysin (Nitritzugabe nach der Braunung) massenspektrometrisch nachgewiesen. Die Anderung des pH-Wertes um eine Einheit, sowie die Anderung der Braunungstemperatur innerhalb des Temperaturbereiches 100–150° C haben auf die qualitative Zusammensetzung der fluchtigen Maillard-Produkte eines betrachteten Modell-Gemisches keinen Einflus. Ein geringer Unterschied wird hinsichtlich der quantitativen Zusammensetzung beobachtet.

Starch, its derivatives and hydrolysis products are well established as industrial products for the food and technical industries. More advanced products, based on starch, are available today, manufactured by biotechnical and chemical processes. They comprise a variety of monomeric compounds like polyols, hydroxycarboxylic acids, glycosides and their derivatives obtained by esterification, etherification and amination. In addition, interesting oligomeric and polymeric products are accessible, based on starch and its derivatives. Selected examples of these products are described as well as their respective production methods. For some products the chemicals synthesis will be compared with the fermentation route, analysing the relative advantages and disadvantages of both. The wide application potential of these “new” products is illustrated with reference to their use in different industries, e. g. in the manufacturing and processing of resins, polymers, detergents, cosmetics, pharmaceuticals and processed foods. Special emphasis will be given to the structural peculiarities of these carbohydrate derivatives, for example chirality, which enables them to act as unique intermediates in the production of biologically active products. Neue Kohlenhydrat-Derivate durch biotechnische und chemische Verfahren. Starke, deren Derivate und Hydrolyseprodukte sind als Industrieprodukte fur den Nahrungsmittel- und den Technischen Sektor wohl etabliert. Heute sind weiter fortgeschrittene auf Starke basierende Produkte verfugbar, die mit biotechnischen oder chemischen Prozessen hergestellt werden. Sie umfassen eine Fulle monomerer Verbindungen wie Polyole, Hydroxycarbonsauren und Glycoside sowie deren Derivate, die durch Veresterung, Veretherung oder Aminierung erhalten werden konnen. Aber auch interessante oligomere und polymere Produkte sind auf der Basis von Starke zuganglich. Ausgewahlte Beispiele dieser Produkte werden beschrieben sowie auch ihre Herstellung. Dabei werden fur einige Produkte der chemische Weg mit dem biotechnischen Weg verglichen und die Vor- bzw. Nachteile analysiert. Das breite Anwendungspotential dieser “neuen” Produkte wird and Hand ihrer Verwendung in verschiedenen Industriezweigen illustriert, z. B. bei der Herstellung und Verarbeitung von Harzen, Polymeren, Waschmitteln, kosmetischen Produkten, pharmazeutischen Verbindungen und konfektionierten Nahrungsmitteln. Hierbei wird besonderer Wert auf die strukturellen Besonderheiten dieser Kohlenhydratderivate gelegt, wie ihre Chiralitat, die sie befahigen, als einzigartige Zwischenprodukte bei der Herstellung biologisch aktiver Produkte zu wirken.

High-resolution, 1 H- (360 and 400 MHz) and 13 C-n.m.r. (90.52 and 100.57 MHz) spectra of the mutarotated N -(1-deoxy- d -fructos-1-yl)- l -amino acids (“fructose-amino acids”) 1–14 in D 2 O are reported. The 1 H spectra allow unambiguous assignment of the signals of the major constituents (β-pyranose forms). Signals of the other forms are not well resolved and therefore not interpreted. The 13 C spectra of 1–14 show ∼64% of β-pyranose, ∼15% of α-furanose, ∼15% of β-furanose, and ∼6% of α-pyranose forms. For N -(1-deoxy- d -fructos-1-yl)- l -alanine ( 2 ), 2% of the keto form is present. In solution in D 2 O, H-1 of the fructose moieties undergoes a slow H/D-exchange, which is strongly accelerated at more-basic pH values. Compound 2 is stable over the pH range 0.7–11.9, as revealed by 13 C-n.m.r. spectroscopy. The 13 C-shift changes caused by protonation/deprotonation are given. There is no significant change in the ratios of the various forms with change in pH.

Benzyl esters of saturated normal and some branched fatty acids (C 1 -C 12 ) and of saturated and unsaturated even-numbered long chain fatty acids (C 14 -C 20 ) were prepared by reaction with phenyldiazomethane. Mass spectra of the individual esters were recorded. A mixture of all the prepared saturated esters was separated on an SE-30 column and identified in the μg range by a combination of gas chromatography and mass spectrometry. Separation of saturated and unsaturated long chain fatty acid benzyl esters was achieved on an EGSS-X column at 210°. A general fragmentation scheme for this class of substances is proposed and the formation of the main fragments is discussed.