Search results for "NOE"

Tonoplast subcellular localization of maize cytochrome b5 reductases

2000

Plant cytochrome b 5 reductases (b 5 R) are assumed to be part of an ER-associated redox chain that oxidizes NADH to provide electrons via cytochrome b5 (cyt b 5 ) to ER-associated fatty acyl desaturase and related hydroxylases, as in mammalian cells. Here we report on cDNA cloning of a novel maize b 5 R, NFR II, strongly related to a previously cloned cDNA, NFR I (Bagnaresi et al., 1999, Biochem, J. 338, 499-5051. Maize b 5 R isoforms are produced by a small multi-gene family. The NFR cDNAs were shown to encode active b 5 Rs by heterologous expression in yeast. Both reductases, in addition to Fe 3+ -chelates, efficiently reduced Cu 2+ -chelates. Using a polyclonal antibody able to recogniz…

Lack of phosphoserine phosphatase activity alters pollen and tapetum development in Arabidopsis thaliana.

2015

Formation of mature pollen grain, an essential process for the reproduction of higher plants, is affected in lines that are deficient in the enzymes of the phosphorylated pathway of serine biosynthesis (PPSB). Mutants of phosphoserine phosphatase (PSP), the enzyme that catalyses the last step of PPSB, are embryo-lethal. When they are complemented with a construct carrying PSP1 cDNA under the control of the 35S promoter (psp1.1 35S:PSP1), which is poorly expressed in anther tissues, plants display a wild-type phenotype, but are male-sterile. The pollen from the psp1.1 35S:PSP1 lines are shrunken and unviable. Here we report the morphological alterations that appear in the psp1.1 35S:PSP1 lin…

Development and application of active and passive DOAS instrumentation for the remote sensing measurement of volcanic gas emissions and continuous ge…

2011

Novel σ1 antagonists designed for tumor therapy: Structure – activity relationships of aminoethyl substituted cyclohexanes

2021

Abstract Depending on the substitution pattern and stereochemistry, 1,3-dioxanes 1 with an aminoethyl moiety in 4-position represent potent σ1 receptor antagonists. In order to increase the stability, a cyclohexane ring first replaced the acetalic 1, 3-dioxane ring of 1. A large set of aminoethyl substituted cyclohexane derivatives was prepared in a six-step synthesis. All enantiomers and diastereomers were separated by chiral HPLC at the stage of the primary alcohol 7, and their absolute configuration was determined by CD spectroscopy. Neither the relative nor the absolute configuration had a large impact on the σ1 affinity. The highest σ1 affinity was found for cis-configured benzylamines…

Assembly of the Major and the Minor Capsid Protein of Human Papillomavirus Type 33 into Virus-like Particles and Tubular Structures in Insect Cells

1994

Native virions of human papillomaviruses (HPV) can be isolated from genital lesions only in very limited amounts. Recent studies have shown that virus-like particles can be obtained by expression of the capsid proteins using vaccinia virus recombinants or the baculovirus system. We now present the first detailed characterization of virus-like particles of a human papillomavirus associated with malignant genital lesions, HPV-33, produced in high yield using the baculovirus expression system. Assembly of the major capsid protein L1 alone or together with the minor capsid protein L2 has been obtained. Both spherical virus-like particles of 50-60 nm diameter and tubular structures of either 25-…

Dithiosquarate (dtsq) complexes of nickel(II). Syntheses and crystal structures of [Ni(phen)2(1,2-dtsq)]·3.5H2O, [Ni(phen)2(1,3-dtsq)] and [Ni(tren)(…

2003

Abstract The new nickel(II) complexes [Ni(phen)2(1,2-dtsq)]·3.5H2O (1), [Ni(phen)2(1,3-dtsq)] (2) and [Ni(tren)(1,2-dtsq)] (3) [1,2-dtsq=dianion of 3,4-dimercapto-3-cyclobutene-1,2-dione, 1,3-dtsq=dianion of 3-hydroxy-4-mercapto-2-thioxo-3-cyclobuten-1-one, phen=1,10-phenanthroline and tren=tris(2-aminoethyl)amine] have been synthesized and characterized by single-crystal X-ray diffraction. Their structures are made up of neutral [Ni(phen)2(1,n-dtsq)] [1 (n=2) and 2 n=3)] and [Ni(tren)(1,2-dtsq)] (3) mononuclear units. The nickel atom is six-coordinated in all three cases: four nitrogen atoms from two bidentate phen (1 and 2) or a tetradentate tren (3) groups and either two sulfur (1 and 3)…

ChemInform Abstract: Diels-Alder Reactions of in situ Generated N-Benzoylindolo-2,3- quinodimethane with Carbodienophiles.

2010

The indolo-2,3-quinodimethane (5), generated from 2,3-bis(bromomethyl)indole (4), was trapped with unsymmetrical carbodienophiles or N, N′-p-phenylenedimaleimide to furnish the 1,2,3,4-tetrahydrocarbazoles (6–9). [4 + 2]-Cycloaddition of 5 with tetracyanoethylene gave rise to the tetracyanocarbazole (10) and a subsequent product 11a or 11b. The Diels-Alder reaction of 5 with divinyl sulfone was regiospecific within the detection limits of HPLC analysis. Similarly, the reaction of 5 with N, N′-p-phenylenedimaleimide yielded solely the stereoisomer 9.

Synthesis of 8-aminomorphans with high KOR affinity

2021

2-Azabicyclo[3.3.1]nonanes (morphans) with a (3,4-dichlorophenyl)acetyl group at 2-position and a pyrrolidino moiety at 8-position were designed as conformationally restricted analogs of piperidine-based KOR agonists. The synthesis started with 4-oxopiperidine-2-carboxylic acid comprising 13 reaction steps. At first the ketone 10 was transformed into diester 7 bearing a propionate side chain. Dieckmann condensation of diester 7 to afford bicyclic enolester 14 and subsequent Krapcho deethoxycarbonylation represent the key steps of the synthesis. The enantiomeric pyrrolidines (1S,5R,8R)-5a and (1R,5S,8S)-5a were separated by chiral HPLC. The eutomer (1S,5R,8R)-5a showed high KOR affinity (K-i…

Elemental distribution and structural characterization of GaN/InGaN core-shell single nanowires by Hard X-ray synchrotron nanoprobes

2019

Improvements in the spatial resolution of synchrotron-based X-ray probes have reached the nano-scale and they, nowadays, constitute a powerful platform for the study of semiconductor nanostructures and nanodevices that provides high sensitivity without destroying the material. Three complementary hard X-ray synchrotron techniques at the nanoscale have been applied to the study of individual nanowires (NWs) containing non-polar GaN/InGaN multi-quantum-wells. The trace elemental sensitivity of X-ray fluorescence allows one to determine the In concentration of the quantum wells and their inhomogeneities along the NW. It is also possible to rule out any contamination from the gold nanoparticle …

Cycloaddition reactions of 1-tert-butyl-4-vinylpyrazole

1989

1-tert-Butyl-4-vinylpyrazole1 a reacts with dimethyl acetylenedicarboxylate (DMAD), methyl propiolate (MP) and N-phenylmaleimide (NPMI) affording the indazole derivatives2,3, and5 as a result of a Diels-Alder ([4 + 2]) cycloaddition. With diethylazodicarboxylate (DEAZD), tetracyanoethylene (TCNE) and 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) the reaction takes place exclusively through the olefinic substituent and the adducts6,7, and9 were isolated. The alkenylpyrazoles1 b–d reacted withDMAD and N-phenylmaleimide to give polymers.