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See detailNovel post-digest isotope coded protein labeling method for phospho- and glycoproteome analysis
Fleron, Maximilien ULg; Greffe, Yannick ULg; Musmeci, Davide ULg et al

in Journal of Proteomics (2010), 73(10), 1986-2005

In the field of proteomics there is an apparent lack of reliable methodology for quantification of posttranslational modifications. Present study offers a novel post-digest ICPL quantification strategy ... [more ▼]

In the field of proteomics there is an apparent lack of reliable methodology for quantification of posttranslational modifications. Present study offers a novel post-digest ICPL quantification strategy directed towards characterization of phosphorylated and glycosylated proteins. The value of the method is demonstrated based on the comparison of two prostate related metastatic cell lines originating from two distinct metastasis sites (PC3 and LNCaP). The method consists of protein digestion, ICPL labeling, mixing of the samples, PTM enrichment and MS-analysis. Phosphorylated peptides were isolated using TiO(2), whereas the enrichment of glycosylated peptides was performed using hydrazide based chemistry. Isolated PTM peptides were analyzed along with non enriched sample using 2D-(SCX-RP)-Nano-HPLC-MS/MS instrumentation. Taken together the novel ICPL labeling method offered a significant improvement of the number of identified (∼600 individual proteins) and quantified proteins (>95%) in comparison to the classical ICPL method. The results were validated using alternative protein quantification strategies as well as label-free MS quantification method. On the biological level, the comparison of PC3 and LNCaP cells has shown specific modulation of proteins implicated in the fundamental process related to metastasis dissemination. Finally, a preliminary study involving clinically relevant autopsy cases reiterated the potential biological value of the discovered proteins. [less ▲]

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See detailA novel potassium channel gene, KCNQ2, is mutated in an inherited epilepsy of newborns.
Singh, N. A.; Charlier, Carole ULg; Stauffer, D. et al

in Nature Genetics (1998), 18(1), 25-9

Idiopathic generalized epilepsies account for about 40% of epilepsy up to age 40 and commonly have a genetic basis. One type is benign familial neonatal convulsions (BFNC), a dominantly inherited disorder ... [more ▼]

Idiopathic generalized epilepsies account for about 40% of epilepsy up to age 40 and commonly have a genetic basis. One type is benign familial neonatal convulsions (BFNC), a dominantly inherited disorder of newborns. We have identified a sub-microscopic deletion of chromosome 20q13.3 that co-segregates with seizures in a BFNC family. Characterization of cDNAs spanning the deleted region identified one encoding a novel voltage-gated potassium channel, KCNQ2, which belongs to a new KQT-like class of potassium channels. Five other BFNC probands were shown to have KCNQ2 mutations, including two transmembrane missense mutations, two frameshifts and one splice-site mutation. This finding in BFNC provides additional evidence that defects in potassium channels are involved in the mammalian epilepsy phenotype. [less ▲]

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See detailA novel pyrid-3-yl sulfonylurea, BM 27, effective in brain edema and stroke treatment
Masereel, B.; Renard, P.; Pirotte, Bernard ULg et al

Conference (1994, September)

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See detailNovel Relative ICPL Based Quantitative Phospho- and Glycoproteome Analysis Method
Fleron, Maximilien ULg; Greffe, Yannick ULg; Massart, Anne-Cécile ULg et al

Poster (2010, April 16)

Large scale proteomic analysis remains challenging partially because proteins are inhomogeneous and often influenced by a variety of structural modifications. In particular, these specific chemical ... [more ▼]

Large scale proteomic analysis remains challenging partially because proteins are inhomogeneous and often influenced by a variety of structural modifications. In particular, these specific chemical modifications called posttranslational modifications (PTM) are crucial determinants for the protein function and biological role. Up to now there have been a growing number of studies describing the enrichment and identification of PTM. However, a significant dearth of data offering a reliable methodology for PTM quantification does exist. The present work aims at developing a label based protein PTM quantification strategy and demonstrating its value on comparative analysis of cells originating from two distinct prostate metastasis sites. PC3 and LNCaP cells isolated from bone and lymph node prostate cancer metastasis sites respectively, were lysed and spiked with three non-human proteins serving as internal standards. Following this, the samples were reduced and alkylated, digested with trypsin and subjected to peptide ICPL (isotope coded protein label) labeling. The two peptide containing samples were joined together followed by the affinity isolation of phospho- (using TiO2 metal affinity chromatography) and glycopeptides (oxidized glycans were bound on hydrazide resin). The enriched fraction as well as the flow-through were analyzed on a 2D-(SCX and C18-RP)-nano-HPLC system. The peptide identification and quantification was conducted using electrospray ion-trap mass spectrometer (Bruker, HCT-ultra). Validation of the differentially modulated proteins was conducted in several biological and technical replicates using the label free MSe based quantification strategy. This PTM based, novel relative protein quantification using post-digest ICPL has detected over 598 individual proteins. Of these more than 95 % have been successfully quantified. PTM enrichment methodologies allowed an isolation rate of 91 % and 50 % for phosphorylated and glycosylated proteins respectively. The detailed comparison of PC3 and LNCaP cells has shown specific overexpression of selected proteins indicating differences between these two prostate metastatic cell lines. Several of these modulated proteins have been previously described to be related to prostate cancer (e.g. annexin A2 and vimentin) while others could be considered as potentially novel. These proteins might be implicated in the fundamental process related to metastasis dissemination. However, because of the known discrepancy between cell systems and clinical material, the present study can be regarded only as a step towards elucidation of these complex interactions. [less ▲]

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See detailA novel renal carbonic anhydrase type III plays a role in proximal tubule dysfunction.
JOURET, François ULg; Gailly, Philippe; Martin, D. et al

in Kidney International (2008), 74(1), 52-61

Dysfunction of the proximal tubule (PT) is associated with variable degrees of solute wasting and low-molecular-weight proteinuria. We measured metabolic consequences and adaptation mechanisms in a model ... [more ▼]

Dysfunction of the proximal tubule (PT) is associated with variable degrees of solute wasting and low-molecular-weight proteinuria. We measured metabolic consequences and adaptation mechanisms in a model of inherited PT disorders using PT cells of ClC-5-deficient (Clcn5Y/-) mice, a well-established model of Dent's disease. Compared to cells taken from control mice, those from the mutant mice had increased expression of markers of proliferation (Ki67, proliferative cell nuclear antigen (PCNA), and cyclin E) and oxidative scavengers (superoxide dismutase I and thioredoxin). Transcriptome and protein analyses showed fourfold induction of type III carbonic anhydrase in a kidney-specific manner in the knockout mice located in scattered PT cells. Kidney-specific carbonic anhydrase type III (CAIII) upregulation was confirmed in other mice lacking the multiligand receptor megalin and in a patient with Dent's disease due to an inactivating CLCN5 mutation. The type III enzyme was specifically detected in the urine of mice lacking ClC-5 or megalin, patients with Dent's disease, and in PT cell lines exposed to oxidative stress. Our study shows that lack of PT ClC-5 in mice and men is associated with CAIII induction, increased cell proliferation, and oxidative stress. [less ▲]

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See detailNovel RGD-like molecules based on the tyrosine template design, synthesis, and biological evaluation on isolated integrins alpha(V)beta/alpha(IIb)beta(3) and in cellular adhesion tests
Biltresse, S.; Attolini, M.; Dive, Georges ULg et al

in Bioorganic & Medicinal Chemistry (2004), 12(20), 5379-5393

RGD (Arg-Gly-Asp) peptidomimetics have been designed for covalent anchorage on biomaterials. The tyrosine template was thus equipped with (i) a basic side chain of various flexibility, (ii) an acidic side ... [more ▼]

RGD (Arg-Gly-Asp) peptidomimetics have been designed for covalent anchorage on biomaterials. The tyrosine template was thus equipped with (i) a basic side chain of various flexibility, (ii) an acidic side chain, which incorporated the XPS fluorine tag, and (iii) a spacer-arm terminated by a primary amine for surface grafting. The most active compounds showed IC50 values in the nanomolar range versus isolated human integrins alpha(v)beta(3) and alpha(IIb)beta(3). Preincubation of CaCo2 cells with soluble peptidomimetics (2 and 19a) prevented cellular adhesion on culture plates coated with vitronectin. On the other hand, peptidomimetics (19a and 19b) immobilized on a poly(ethylene)terephthalate membrane (PET) promoted CaCo2 cells adhesion. A modeling study at the ab initio level in MINI-1' basis allowed to compare the various synthetic ligands of integrins and to propose novel pharmacophore structures. (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailNovel role for type E Immunoglobulins: host protection against venoms.
Marichal, Thomas ULg

Scientific conference (2014, October)

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See detailNovel SACS mutation in a Belgian family with sacsin-related ataxia.
Ouyang, Y.; SEGERS, Karin ULg; BOUQUIAUX, Olivier ULg et al

in Journal of the Neurological Sciences (2008), 264(1-2), 73-6

The authors describe the four patients in the first known Belgian family with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS). A novel homozygous missense mutation, NM_014363.3: c.3491T ... [more ▼]

The authors describe the four patients in the first known Belgian family with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS). A novel homozygous missense mutation, NM_014363.3: c.3491T>A in exon 9, of the SACS gene was identified in the present family, which results in an original amino acid of methionine to lysine substitution at amino acid residue 1164 (p.M1164K). Although the cardinal clinical features, i.e., spastic ataxia with peripheral neuropathy, in our patients were similar to those in Quebec patients, our patients exhibited some atypical clinical features, e.g., teenage-onset and absence of retinal hypermyelination. The present family is from Wallonia, and there could be shared ethnicity with the families of Charlevoix-Saguenay. [less ▲]

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See detailNovel scanning procedure enabling the vectorization of entire rhizotron-grown root systems
Lobet, Guillaume ULg; Draye, X.

in Plant Methods (2013), 9(1),

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See detailA novel screening method for hydrogenase-deficient mutants in Chlamydomonas reinhardtii based on in vivo chlorophyll fluorescence and photosystem II quantum yield
Godaux, Damien ULg; Emonds-Alt, Barbara ULg; Berne, Nicolas ULg et al

in International Journal of Hydrogen Energy (2013), 38

In Chlamydomonas reinhardtii, prolonged anaerobiosis leads to the expression of enzymes <br />Received 30 August 2012 belonging to various fermentative pathways. Among them, oxygen-sensitive hydrogenases ... [more ▼]

In Chlamydomonas reinhardtii, prolonged anaerobiosis leads to the expression of enzymes <br />Received 30 August 2012 belonging to various fermentative pathways. Among them, oxygen-sensitive hydrogenases <br />Received in revised form (HydA1/2) catalyze the synthesis of molecular hydrogen from protons and reduced ferre- <br />12 November 2012 doxin in the stroma. In this work, by analyzing wild type and mutants affected in H2 <br />Accepted 16 November 2012 production, we show that maximal PSII photosynthetic electron transfer during the first <br />Available online 21 December 2012 seconds of illumination after a prolonged dark-anaerobiosis period is linearly related to <br />hydrogenase capacity. Based on the specific chlorophyll fluorescence induction kinetics <br />Keywords: typical of hydrogenase-deficient mutants, we set up an in vivo fluorescence imaging <br />Chlamydomonas reinhardtii screening protocol allowing to isolate mutants impaired in hydrogenase expression or <br />Anaerobic photosynthesis activity, as well as mutants altered in related metabolic pathways required for energy <br />Hydrogenase production in anaerobiosis. Compared to previously described screens for mutants <br />Chlorophyll fluorescence impaired in H2 production, our screening method is remarkably fast, sensitive and non- <br />Microalgae invasive. Out of 3000 clones from a small-sized insertional mutant library, five mutants <br />Hydrogen photoproduction were isolated and the most affected one was analyzed and shown to be defective for the <br />hydrogenase HydG assembly factor. [less ▲]

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See detailA novel seizure-induced synaptotagmin gene identified by differential display.
Babity, J. M.; Armstrong, J. N.; Plumier, Jean-Christophe ULg et al

in Proceedings of the National Academy of Sciences of the United States of America (1997), 94(6), 2638-41

Systemic administration of kainic acid, a cyclic analogue of glutamate, produces many of the clinical features of human temporal lobe epilepsy and status epilepticus in rats, including the induction of ... [more ▼]

Systemic administration of kainic acid, a cyclic analogue of glutamate, produces many of the clinical features of human temporal lobe epilepsy and status epilepticus in rats, including the induction of motor convulsions and the degeneration of neurons in the hippocampus and piriform cortex. Differential display PCR was used to identify mRNAs that are differentially expressed between degenerating and nondegenerating tissues in the brain after kainic acid-induced seizure activity. A novel cDNA fragment expressed in the degenerating hippocampus and piriform cortex, but not in the nondegenerating parietal cortex, was identified, cloned, and sequenced. This novel cDNA fragment identified a new member of the synaptotagmin gene family that is rapidly and transiently induced in response to seizure activity. Differential expression of this synaptotagmin gene, syt X, was confirmed by Northern blot analysis and in situ hybridization. This novel, inducible synaptotagmin gene may provide a direct link between seizure-induced neuronal gene expression and subsequent modulation of synaptic structure and function. [less ▲]

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See detailA novel SETI strategy targeting the solar focal regions of the most nearby stars
Gillon, Michaël ULg

in Acta Astronautica (2013), 94

Many hypotheses have been raised to explain the famous Fermi paradox. One of them is that self-replicating probes could have explored the whole Galaxy, including our Solar System, and that they are still ... [more ▼]

Many hypotheses have been raised to explain the famous Fermi paradox. One of them is that self-replicating probes could have explored the whole Galaxy, including our Solar System, and that they are still to be detected. In this scenario, it is proposed here that probes from neighboring stellar systems could use the stars they orbit as gravitational lenses to communicate efficiently with each other. Under this hypothesis, a novel SETI approach would be to monitor the solar focal regions of the most nearby stars to search for communication devices. The envisioned devices are probably not detectable by imagery or stellar occultation, but an intensive multi-spectral monitoring campaign could possibly detect some communication leakages. Another and more direct option would be to message the focal regions of nearby stars in an attempt to initiate a reaction. [less ▲]

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See detailThe Novel since 1970
Ledent, Bénédicte ULg; Maes, Hena ULg

in Arnold, A. James; Kutzinski, Vera M.; Phaf-Rheinberger, Ineke (Eds.) et al A History of Literature in the Caribbean: Volume 2: English- and Dutch-Speaking Regions (2001)

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See detailNovel smooth muscle markers reveal abnormalities of the intestinal musculature in severe colorectal motility disorders
Wedel, Thilo; Van Eys, Guillaume; Waltregny, David ULg et al

in Neurogastroenterology and Motility (2006), 18(7), 526-538

Histopathological studies of gastrointestinal motility disorders have mainly focused on enteric nerves and interstitial cells of Cajal, but rarely considered the enteric musculature. Here we used both ... [more ▼]

Histopathological studies of gastrointestinal motility disorders have mainly focused on enteric nerves and interstitial cells of Cajal, but rarely considered the enteric musculature. Here we used both classical and novel smooth muscle markers and transmission electron microscopy (TEM) to investigate muscular alterations in severe colorectal motility disorders. Full-thickness specimens from Hirschsprung's disease, idiopathic megacolon, slow-transit constipation and controls were stained with haematoxylin/eosin (HE) and Masson's trichrome (MT), incubated with antibodies against smooth muscle alpha-actin (alpha-SMA), smooth muscle myosin heavy chain (SMMHC), smoothelin (SM) and histone deacetylase 8 (HDAC8) and processed for TEM. Control specimens exhibited homogeneous immunoreactivity for all antibodies. Diseased specimens showed normal smooth muscle morphology by HE and MT. While anti-alpha-SMA staining was generally normal, immunoreactivity for SMMHC, HDAC8 and/or SM was either absent or focally lacking in Hirschsprung's disease (80%), idiopathic megacolon (75%) and slow-transit constipation (70%). Ultrastructurally, clusters of myocytes with noticeably decreased myofilaments were observed in all diseases. SMMHC and the novel smooth muscle markers SM and HDAC8 often display striking abnormalities linked to the smooth muscle contractile apparatus unnoticed by both routine stainings and alpha-SMA, suggesting specific defects of smooth muscle cells involved in the pathogenesis of gastrointestinal motility disorders. [less ▲]

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See detailThe novel somatostatin analog SOM230 has a broad spectrum of inhibitory action on hormone release by human somatotroph, corticotroph and PRL-secreting pituitary adenomas in vitro
Hofland, L. J.; Van Der Hoek, J.; Van Koetsveld, P. M. et al

in The 85th Annual Meeting of the Endocrine Society - Abstract book (2003)

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See detailThe novel somatostatin analog SOM230 is a potent inhibitor of hormone release by growth hormone- and prolactin-secreting pituitary adenomas in vitro.
Hofland, Leo J; van der Hoek, Joost; van Koetsveld, Peter M et al

in Journal of Clinical Endocrinology and Metabolism (2004), 89(4), 1577-1585

To determine the inhibitory profile of the novel somatostatin (SRIF) analog SOM230 with broad SRIF receptor binding, we compared the in vitro effects of SOM230, octreotide (OCT), and SRIF-14 on hormone ... [more ▼]

To determine the inhibitory profile of the novel somatostatin (SRIF) analog SOM230 with broad SRIF receptor binding, we compared the in vitro effects of SOM230, octreotide (OCT), and SRIF-14 on hormone release by cultures of different types of secreting pituitary adenomas. OCT (10 nM) significantly inhibited GH release in seven of nine GH-secreting pituitary adenoma cultures (range, -26 to -73%), SOM230 (10 nM) in eight of nine cultures (range, -22 to -68%), and SRIF-14 (10 nM) in six of six cultures (range, -30 to -75%). The sst analysis showed predominant but variable levels of somatostatin receptor (sst)(2) and sst(5) mRNA expression. In one culture completely resistant to OCT, SOM230 and SRIF-14 significantly inhibited GH release in a dose-dependent manner with an IC(50) value in the low nanomolar range. In the other cultures, SOM230 showed a lower potency of GH release inhibition (IC(50), 0.5 nM), compared with OCT (IC(50), 0.02 nM) and SRIF-14 (IC(50), 0.02 nM). A positive correlation was found between sst(2) but not sst(5) mRNA levels in the adenoma cells and the inhibitory potency of OCT on GH release in vivo and in vitro, and the effects of SOM230 and SRIF-14 in vitro. In three prolactinoma cultures, 10 nM OCT weakly inhibited prolactin (PRL) release in only one (-28%), whereas 10 nM SOM230 significantly inhibited PRL release in three of three cultures (-23, -51, and -64.0%). The inhibition of PRL release by SOM230 was related to the expression level of sst(5) but not sst(2) mRNA. Several conclusions were reached. First, SOM230 has a broad profile of inhibition of tumoral pituitary hormone release in the low nanomolar range, probably mediated via both sst(2) and sst(5) receptors. The higher number of responders of GH-secreting pituitary adenoma cultures to SOM230, compared with OCT, suggest that SOM230 has the potency to increase the number of acromegalic patients which can be biochemically controlled. Second, compared with OCT, SOM230 is more potent in inhibiting PRL release by mixed GH/PRL-secreting adenoma and prolactinoma cells. [less ▲]

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See detailA novel splice variant in the N-propeptide of COL5A1 causes an EDS phenotype with severe kyphoscoliosis and eye involvement.
Symoens, Sofie; Malfait, Fransiska; Vlummens, Philip et al

in PloS one (2011), 6(5), 20121

BACKGROUND: The Ehlers-Danlos Syndrome (EDS) is a heritable connective tissue disorder characterized by hyperextensible skin, joint hypermobility and soft tissue fragility. The classic subtype of EDS is ... [more ▼]

BACKGROUND: The Ehlers-Danlos Syndrome (EDS) is a heritable connective tissue disorder characterized by hyperextensible skin, joint hypermobility and soft tissue fragility. The classic subtype of EDS is caused by mutations in one of the type V collagen genes (COL5A1 and COL5A2). Most mutations affect the type V collagen helical domain and lead to a diminished or structurally abnormal type V collagen protein. Remarkably, only two mutations were reported to affect the extended, highly conserved N-propeptide domain, which plays an important role in the regulation of the heterotypic collagen fibril diameter. We identified a novel COL5A1 N-propeptide mutation, resulting in an unusual but severe classic EDS phenotype and a remarkable splicing outcome. METHODOLOGY/PRINCIPAL FINDINGS: We identified a novel COL5A1 N-propeptide acceptor-splice site mutation (IVS6-2A>G, NM_000093.3_c.925-2A>G) in a patient with cutaneous features of EDS, severe progressive scoliosis and eye involvement. Two mutant transcripts were identified, one with an exon 7 skip and one in which exon 7 and the upstream exon 6 are deleted. Both transcripts are expressed and secreted into the extracellular matrix, where they can participate in and perturb collagen fibrillogenesis, as illustrated by the presence of dermal collagen cauliflowers. Determination of the order of intron removal and computational analysis showed that simultaneous skipping of exons 6 and 7 is due to the combined effect of delayed splicing of intron 7, altered pre-mRNA secondary structure, low splice site strength and possibly disturbed binding of splicing factors. CONCLUSIONS/SIGNIFICANCE: We report a novel COL5A1 N-propeptide acceptor-splice site mutation in intron 6, which not only affects splicing of the adjacent exon 7, but also causes a splicing error of the upstream exon 6. Our findings add further insights into the COL5A1 splicing order and show for the first time that a single COL5A1 acceptor-splice site mutation can perturb splicing of the upstream exon. [less ▲]

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See detailNovel Stealthy Gd(III)-DOTA/polymer Conjugates for Magnetic Resonance Imaging (MRI)
Grogna, Mathurin ULg; Bémelmans, Stéphanie ULg; Vanasschen, Christian ULg et al

Conference (2009, May 14)

Magnetic resonance imaging (MRI) is a routine diagnostic tool in modern clinical medicine. MRI has many advantages as a diagnostic imaging modality. It is noninvasive, delivers no radiation, and has ... [more ▼]

Magnetic resonance imaging (MRI) is a routine diagnostic tool in modern clinical medicine. MRI has many advantages as a diagnostic imaging modality. It is noninvasive, delivers no radiation, and has excellent (submillimeter) spatial resolution. Some Gadolinium(III) complexes are commonly used to enhance the contrast between adjacent tissues when the resolution/sensitivity of MRI is too low. Because free Gd3+ is very toxic in doses required for MRI, Gd(III) is chelated by poly(amino-carboxylate) such as diethylenetriamine pentaacetic acid (DTPA) or 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). Although DTPA/Gd3+ and DOTA/Gd3+ are water soluble, they have a very short circulation lifetime in blood, a low molecular weight and a short rotational time that make the contrast poor. To enhance the contrast, the Gd3+/complex doses have to be increased. In order to increase the sensitivity of the technique, while not increasing the concentration of the contrast agent, we were investigating different strategies to improve (i) the circulation lifetime in blood, (ii) the relaxation rate of Gd(III) (and consequently, the contrasting efficiency) and (iii) the targeting of the contrast agent. This presentation aims at reporting how a multifunctional (co)polymer can be designed and exploited for improving the contrasting ability and bioavailability of gadolinium-based complexes. [less ▲]

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See detailNovel Strategies towards aminophosphonic derivatives by [4+2] cycloadditions
Monbaliu, Jean-Christophe ULg

Doctoral thesis (2008)

Aminophosphonic and related compounds were almost unknown 50 years ago, but today the literature data have considerably increased. Their negligible mammalian toxicity and their similarity with aminoacids ... [more ▼]

Aminophosphonic and related compounds were almost unknown 50 years ago, but today the literature data have considerably increased. Their negligible mammalian toxicity and their similarity with aminoacids confer on these compounds a top place as potential candidates for drugs. The discovery of numerous natural aminophosphonic derivatives endowed with biological properties useful to both medicinal and agricultural fields enhanced the infatuation for synthetic analogs and homologs. Intensive work has been performed towards alpha-aminophosphonic compounds, the direct analogs of natural alpha-aminoacids, disclosing versatile strategies, compatible both with molecular diversity and asymmetric synthesis. Less synthetic effort was devoted to the synthesis of higher homologs. Recent developments of the Diels-Alder reaction offer an asymmetric and convergent entry to various six-membered highly functionalizable key intermediates, compatible with molecular variety. As it is, the Diels-Alder (D-A) reaction should provide an original and versatile entry to beta-, gamma- and delta-aminophosphonic compounds, a challenging research area. As a direct consequence of the strategy, one of the two D-A partners (diene or dienophile) will act as vehicle for the phosphonate moiety. By contrast to its common use for the stabilization of alpha-negative charges, its implication in D-A reactions remains scarce. Indeed, the phosphonate moiety is not an efficient substituent susceptible to activate the D-A reaction; its use requires compensation by the activation of the other partner or by specific activation. Both synthetic organic and computational chemistry will furnish information to propose a fine understanding of the key D-A steps, in view to optimize the achievement of the corresponding cycloadducts. These cycloadducts will be considered as synth-/chirons for the synthesis of aminophosphonic compounds. [less ▲]

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See detailA novel strategy for the dispersion, selective deposition and decoration of carbon nanotubes
Detrembleur, Christophe ULg; Lou, Xudong; Stoffelbach, François et al

Poster (2005, May 11)

Detailed reference viewed: 11 (1 ULg)