The Identification of Mono-, Di-, Tri-, and Tetragalactosyl-diacylglycerols and their Natural Estolides in Oat Kernels

Oat kernels were extracted with methanol, and glycolipid-enriched fractions were prepared using silica solid phase extraction. Using direct infusion electrospray ionization (ESI) tandem mass spectrometry (MS), high performance liquid chromatography (HPLC)-ESI-MS, and HPLC-atmospheric pressure chemical ionization (APCI)-MS, we confirmed previous reports that digalactosyldiacylglycerol (DGDG) was the most abundant glycolipid in oat kernels and confirmed a previous report of the presence of a DGDG mono-estolide in oat kernels. In the current study we also identified several additional natural galactolipid estolides: two new DGDG estolides (di- and tri-estolides), two trigalactosyldiacylglycerol (TriGDG) estolides (mono- and di-estolides), and one tetragalactosyldiacylglycerol (TetraGDG) estolide (mono-estolide). The levels of total galactolipid estolides in oat kernels were estimated to be about 29% of the total glycolipid fraction. To our knowledge, this report is the first evidence of natural di- and tri-estolides of polar lipids.     

Quantitative determination of Tri-, Di-,monooleins and free oleic acid by the thin layer chromatography-flame lonization detector system using internal standards and boric acid impregnated chromarod

The separation conditions for hydrolysates of triglycerides by lipase and their quantitative determination are discussed for a thin layer chromatography-flame ionization detector system utilizing internal standards. The complete separation of glyceride hydrolysis mixtures (triolein 1,3-diolein, 1,2-diolein, 1-monoolein and oleic acid) was achieved on a 3% boric acid-impregnated Chromarod S-II by development with benzene/chloroform/acetic acid (70∶30∶2, v/v/v) (mobile phase A) or hexane/ ether/acetic acid (70∶30∶1, v/v/v) (mobile phase B). Mobile phase B had an advantage over mobile phase A in terms of free space to add internal standards for simultaneous quantitation and was employed.p-Hydroxybenzoic acid andp-carboethoxy benzyl alcohol, which appeared between 1,2-diolein and 1-moloolein, were adopted as the internal standards. The calibration curves relating internal standards to each glyceride were all approximated by the equations Y=aX^b giving high correlations. The method was applied to hydrolysis of triolein by pancreatic lipase. Part of this investigation was reported at the annual meeting of JOCS in Tokyo, November 1982.     

Reaction of p-Hydroxycinnamyl Alcohols with Transition Metal Salts. 2. Preparation of Guaiacyl/Syringyl Di-, Tri-, and Tetralignols

Treatment of coniferyl alcohol (CA), sinapyl alcohol (SA), and their mixtures with copper or manganese salts yielded nine dilignols, five trilignols, and one tetralignol. The lignols were composed of guaiacyl (G) or CA units and syringyl (S) or SA units linked together by β-O-4 (b), β-5 (c for coumaran), β–β (r for resinol), and/or a novel γ-β (gb) linkage. None of the isolated lignols contained 5–5′ (biphenyl), 4-O-5, or β-1 linkages. Spectral analysis (¹H NMR, ¹³C NMR, MS) and comparison with authentic compounds confirmed the structures of the dilignols as G-b-CA, G-b-SA, S-b-CA, S-b-SA, G-c-CA, S-c-CA, G-r-G, G-r-S, and S-r-S; the trilignols as G-b-S-r-S, G-b-S-c-CA, S–b-S-r-S, and G-c-G-gb-G; and the only tetralignol as G-b-S-r-S-b-G.     

O2 and N2O activation by Bi-, Tri-, and tetranuclear Cu clusters in biology

Copper-cluster sites in biology exhibit unique spectroscopic features reflecting exchange coupling between oxidized Cu's and e (-) delocalization in mixed valent sites. These novel electronic structures play critical roles in O 2 binding and activation for electrophilic aromatic attack and H-atom abstraction, the 4e (-)/4H (+) reduction of O 2 to H 2O, and in the 2e (-)/2H (+) reduction of N 2O. These electronic structure/reactivity correlations are summarized below.     

Polymerization of rac-lactide catalyzed by group 4 metal complexes containing chiral N atoms

The hydroxyl- and phenoxy-bridged dinuclear zirconium and hafnium complexes, 1 and 2, containing a chiral N atom in the N₂O₂ ligand (H₂L = 2-(((2-pyridylmethyl)(2-hydroxyphenyl)amino)methyl)-4,6-di(tert-butyl)phenol) were used as catalysts for the ring-opening polymerization of rac-lactide. Experiments prove that 1 and 2 are living and controlled catalytic systems with activity up to 3.25 g_pol mmol_ini ⁻¹ h⁻¹. The isotactic-rich polylactides in a narrow polydispersity (M _w/M _n = 1.01–1.13) were produced with enantiomeric complexes 1 and 2 (P _m = 0.65–0.73). The kinetic studies show a first-order dependency in both monomer and initiator. The initiation mechanism is discussed on the basis of the MALDI-TOF MS and ¹H NMR spectra of the rac-LA oligomer prepared by 1.     

Copper complexes of some tetra- and pentapeptides containing polyfunctional amino acids

Copper complexes of some tetra- and pentapeptides [(I)-(VI)] containing lysine and ornithine are spectrophotometrically examined. It is shown that all tetra- and pentapeptides form red or reddish violet copper complexes with λ_max 515–540 nm, and copper-peptide ratio 1:1. The results achieved confirmed that the N⁶-amino group of the lysine residues or the N⁵-amino group of the ornithine residues do not participate in complex formation of tetra- and pentapeptides even when lysine or ornithine form the N-terminal amino acid in the peptide.     

Copper complexes of some tetra- and pentapeptides containing polyfunctional amino acids

Copper complexes of some tetra- and pentapeptides [(I)-(VI)] containing lysine and ornithine are spectrophotometrically examined. It is shown that all tetra- and pentapeptides form red or reddish violet copper complexes with λ_max 515–540 nm, and copper-peptide ratio 1:1. The results achieved confirmed that the N⁶-amino group of the lysine residues or the N⁵-amino group of the ornithine residues do not participate in complex formation of tetra- and pentapeptides even when lysine or ornithine form the N-terminal amino acid in the peptide.     

1,2,3,4-丁烷四羧酸过渡金属配合物的制备和表征

用过渡金属盐与 1,2 ,3,4 -对所制金属配合物的组成和结构进行了表征。利用热重分析对该配合物的热稳定性进行了研究 ,得出其热稳定性次序为 :Cu2 C8H6O8相似文献   

N2,N2,N6,N6-四乙基-4-醛基吡啶-2,6-二甲酰胺的合成

以2,6-二甲基吡啶为原料,经KMnO4氧化、二乙胺酰胺化、吡啶环自由基亲核取代反应得到N2,N2,N6,N6-四乙基-4-羟甲基吡啶-2,6-二甲酰胺,然后用Sarret试剂氧化得到标题化合物并探讨了氧化反应的最佳条件,产物结构经1HNMR、IR和MS得到表征.该产物是合成新型吡啶类有机配体的重要中间体.     

Partial argentation resin chromatography (PARC): II. Separation of saturated and Mono-, Di-, Tri- and tetraenoic fatty esters

Partial argentation resin chromatography (PARC) was used to separate a mixture of saturated and monoenoic, dienoic, trienoic and tetraenoic fatty esters. A series of columns containing XN1010 sulfonic acid resin silvered in the range of 17~91% of theoretical (meaning 17~91% of the sulfonic acid protons were replaced by silver ions) were prepared and were used to correlate the percentage silver with the separation and the retention times of unsaturated fatty esters.cis-Trienoic and tetraenoic fatty esters were eluted with methanol on PARC columns containing 36 and 17% silver. Partial silvering of the resin improved peak shapes while sample elution time and elution volume were reduced. Application of PARC to the separation of mixtures of fatty acids and mixtures of triglycerides was investigated and found to be not feasible with the present system.     

Absorption of NO2/N2O4 in nitric acid

Laboratory-scale measurements were performed on the absorption of NO₂ gas into diluted nitric acid. The concentration of NO₂ gas, which represents an NO₂/N₂O₄ equilibrium, varied from 1000 to 20000 ppm, the carrier gas being nitrogen. The concentration of nitric acid ranged from 15 to 60 mass-%. The absorption experiments were carried out in a double stirred cell, with a defined gas/liquid interface as the mass transfer area. The liquid phase was conducted periodically and the gas phase continuously. Mass flow rates were determined. The well-known film model of absorption was used for analyzing the experimental results. Only the N₂O₄ species was considered to pass the gas/liquid interface. The measured data yielded values of H(k D₁)^1/2 as well as their variation with temperature and nitric acid concentration.     

脂肪酸甲酯磺酸盐的复合性能研究

用MES同AES-2、LAS或AOS进行复合,测定复合样品的表面张力、润湿力、泡沫性能及黏度,并对复合体系的性能进行讨论。结果表明：MES与AES-2复合体系的表面张力和润湿力具有负的协同效应,泡沫体积和黏度明显增加;MES与LAS复合体系的表面张力、润湿力和发泡性能具有负的协同效应,黏度明显增加;而MES与AOS体系的表面张力具有负的协同效应,润湿力有很好的协同效应,泡沫体积明显增加,但黏度无太大变化。在MES与AES-2、LAS或AOS复合体系中,当MES的质量分数为50%时,体系表现出特别的性能。     

Copper(II) complexes derived from bidentate N,O-ligands for catalytic aerobic oxidation

Two Cu^II complexes based on bidentate N,O-ligands have been synthesized and structurally characterized. X-ray structural analysis revealed that in complex 1 the Cu^II center adopts an unusual near tetrahedral coordination geometry, while the Cu^II core in 2 is traditionally square planar, albeit both of them have a N₂O₂ coordination environment and two compounds are mononuclear bis-ligand neutral complexes. A two-dimensional sheet-like network was observed in 2, resulting from the weak Cu…O contacts between the nitrato groups and axial Cu^II sites. Both complexes were tested for catalytic aerobic oxidation of benzylic alcohol and the results indicated that 2 was a better catalyst than 1. High yield of benzaldehyde was observed when using 2 as a catalyst in combination with TEMPO in an aqueous potassium carbonate solution at 60 °C.     

Synthesis,structure, and reactivity of yttrium complexes with chiral biaryldiamine-based N4-ligands

The chiral biaryl-based N₄-ligands, (R)-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-bis(pyrrol-2-ylmethyleneamino)-1,1′-binaphthyl (1H₂) and (S)-2,2′-bis(pyrrol-2-ylmethyleneamino)-6,6′-dimethyl-1,1′-biphenyl (2H₂), can effectively stabilize the chiral rare earth metal chloride complexes such as 1-YCl(dme) (3) and 2-YCl(dme) (4), which offers important intermediates for the preparation of chiral rare earth catalysts containing the M–C or M–X (X = heteroatom) bonds. For example, treatment of 3 with half equiv of 1Na₂ in THF gives the binuclear complex 1-Y(thf)-1-Y(thf)-1 (5) in 70% yield. These complexes have been characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction analyses. The complex 5 is an active catalyst for the ring-opening polymerization of rac-lactide, affording isotactic-rich polylactides.     

Ultrafiltration of colloidal solutions containing L, D-phenylalanine, trans-4-hydroxy-L-proline and their copper complexes

The effects of the composition of a surfactant colloidal solution containing nonylphenylpolyoxyethylene ether, theracemic mixture of L,D-phenylalanine, trans-4-hydroxy-L-proline and/or their copper complexes upon the flux of permeate and the resistance of the hydrophilic membrane and additional layer formed during ultrafiltration were studied. It was found that colloidal solutions containing the nonionic surfactant and additionally phenylalanine, the selector and their complexes with copper can be ultrafiltrated through hydrophilic membranes made of regenerated cellulose with a cut-off of 10 kDa with satisfactory fluxes. Both the permeate flux and resistance depend upon the concentration of the surfactant, but the effect of phenylalanine and the selector is negligible. The decisive effect was observed for copper complexes with phenylalanine and the selector as the complexes significantly decrease the permeate flux and increase the resistance of the additional layer.     

Characterization of Novel Di-, Tri-, and Tetranucleotide Microsatellite Primers Suitable for Genotyping Various Plant Pathogenic Fungi with Special Emphasis on Fusaria and Mycospherella graminicola

The goals of this investigation were to identify and evaluate the use of polymorphic microsatellite marker (PMM) analysis for molecular typing of seventeen plant pathogenic fungi. Primers for di-, tri-, and tetranucleotide loci were designed directly from the recently published genomic sequence of Mycospherlla graminicola and Fusarium graminearum. A total of 20 new microsatellite primers as easy-to-score markers were developed. Microsatellite primer PCR (MP-PCR) yielded highly reproducible and complex genomic fingerprints, with several bands ranging in size from 200 to 3000 bp. Of the 20 primers tested, only (TAGG)4, (TCC)5 and (CA)7T produced a high number of polymorphic bands from either F. graminearum or F. culmorum. (ATG)5 led to successful amplifications in M. graminicola isolates collected from Germany. Percentage of polymorphic bands among Fusarium species ranged from 9 to 100%. Cluster analysis of banding patterns of the isolates corresponded well to the established species delineations based on morphology and other methods of phylogenetic analysis. The current research demonstrates that the newly designed microsatellite primers are reliable, sensitive and technically simple tools for assaying genetic variability in plant pathogenic fungi.