  Photoactivated 1,3-dipolar cycloaddition for the rapid preparation of 18F labelled radiotracersThonon, David  ; Goukens, Eve ; Kaisin, Geoffroy et alin Tetrahedron (2011), 67 Detailed reference viewed: 25 (15 ULg) Cyclodimerization by ring-closing metathesis: synthesis, computational and biological evaluation of novel bis-azetidinyl-macrocycles; Dive, Georges ; et alin Tetrahedron (2010), 66 Detailed reference viewed: 16 (5 ULg)A new tripodal ligand system based on the iminophosphorane functional group. Part 1: Synthesis and characterization; Delaude, Lionel ; Noels, Alfred in Tetrahedron (2007), 63(30), 7003-7008 Two tripodal alcohols, viz., 1,1,1-tris(hydroxymethyl) ethane and alpha, alpha, alpha-tris(hydroxymethyl) toluene were converted by an efficient multi-step pathway involving azide formation into the ... [more ▼] Two tripodal alcohols, viz., 1,1,1-tris(hydroxymethyl) ethane and alpha, alpha, alpha-tris(hydroxymethyl) toluene were converted by an efficient multi-step pathway involving azide formation into the corresponding tris(iminophosphorane) scaffolds bearing cyclopentyl (Cp) or phenyl groups on their phosphorus atoms, R-C(CH2-N] PR'(3))(3) (R Me or Ph, R'=Cp or Ph). The synthesis of some representative transition-metal complexes of Cu(I), Cu(II), Ni(II), and Pd(II) bearing these new tridentate ligands is also reported. (C) 2007 Elsevier Ltd. All rights reserved. [less ▲] Detailed reference viewed: 34 (2 ULg)Synthesis of biphenylamines via Suzuki-Miyaura cross-coupling reactions; Delaude, Lionel ; Demonceau, Albert et alin Tetrahedron (2007), 63(12), 2657-2663 A small library of meta- and para-biphenylamines substituted by various alkyl, alkoxy, phenoxy, or halogeno groups on their aromatic rings was synthesized via Suzuki-Miyaura cross-coupling between ... [more ▼] A small library of meta- and para-biphenylamines substituted by various alkyl, alkoxy, phenoxy, or halogeno groups on their aromatic rings was synthesized via Suzuki-Miyaura cross-coupling between bromoanilines and arylboronic acids using palladium catalysts. The experimental conditions were carefully adjusted to accommodate a wide range of substituents, in terms of electron-withdrawing or -donating ability and steric bulk. In some cases, protection and deprotection of the amine function via its trifluoroacetamide were added to the reaction sequence in order to facilitate the cross-coupling step. (c) 2007 Elsevier Ltd. All rights reserved. [less ▲] Detailed reference viewed: 30 (3 ULg)The search for tolerant Lewis acid catalysts. Part2: enantiopure cycloalkyldialkylsilyl triflimide catalysts; ; et al in Tetrahedron (2007), 63(35), 8449-8462 Detailed reference viewed: 21 (7 ULg)Investigation of the inhibition mechanism of coumarins on chymotrypsin by mass spectrometry; ; et al in Tetrahedron (2003) Detailed reference viewed: 12 (0 ULg)Synthesis, hydrolysis, biochemical and theoretical evaluation of 1,4-bis(alkoxycarbonyl)azetidin-2-ones as potential elastase inhibitors; Dive, Georges ; et alin Tetrahedron (2002), 58(12), 2423-2433 A series of 1,4-bis(alkoxycarbonyl)azetidin-2-ones, designed as potential suicide-inhibitors of serine proteases, has been synthesized and evaluated against porcine pancreatic elastase (PPE). The most ... [more ▼] A series of 1,4-bis(alkoxycarbonyl)azetidin-2-ones, designed as potential suicide-inhibitors of serine proteases, has been synthesized and evaluated against porcine pancreatic elastase (PPE). The most active compound (K(i)similar to10 muM; reversible inhibitor) was equipped with phenethyloxycarbonyl and benzyloxycarbonyl side-chains at positions N1 and C4, respectively, with the (S)-configuration. H-1 NMR spectroscopic analysis of the reaction mixtures showed that the ester function is preferentially hydrolyzed, in both chemical and enzyme-catalyzed reactions, with regard to the azetidinone and urethane functions. Considering the three potentially sensitive carbonyl functions and the two stereoisomers, ab initio calculations were performed to determine the energetic barriers required to reach the transition state structures of hydrolysis in a model of the enzyme pocket. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲] Detailed reference viewed: 6 (0 ULg)Biosynthetic studies on adaline and adalinine, two alkaloids from ladybird beetles (Coleoptera : Coccinellidae)Laurent, Pascal ; ; et alin Tetrahedron (2001), 57(16), 3403-3412 The biosynthesis of the homotropane alkaloid (-)-adaline in the coccinellid beetle Adalia bipunctata has been studied by incorporation experiments with [1-C-14] and [2-C-14]acetate. A degradation scheme ... [more ▼] The biosynthesis of the homotropane alkaloid (-)-adaline in the coccinellid beetle Adalia bipunctata has been studied by incorporation experiments with [1-C-14] and [2-C-14]acetate. A degradation scheme was developed which selectively afforded benzoic acid containing the carbonyl carbon atom of adaline. The labelling pattern thus obtained indicated that the alkaloid is biosynthesized via a polyacetate pathway. Moreover, feeding A. bipunctata adults with (-)-[10,10,11,11,12,12,13,13,14,14,14-H-2(11)]adaline . HCl afforded (-)-[7,7,8,8,9,9,10,10,11,11,11-H-2(11)]adalinine, demonstrating a biogenetic relationship between the two alkaloids. possible mechanisms for this conversion are discussed. Finally, the synthetic scheme devised to obtain (+/-)-6-acetonyl-2-pentyl-1-piperideine did not yield the target compound, but afforded instead (+/-)-adaline in moderate yields. This unexpected result gives support to the hypothesis that this piperideine could be a key intermediate in the biosynthesis of adaline. [less ▲] Detailed reference viewed: 30 (1 ULg)Study of the ring closure reaction of o-aminoarylsulfonamides with 1,1’-thiocarbonyldiimidazoleDe Tullio, Pascal ; Pirotte, Bernard ; et alin Tetrahedron (1998), 54 Detailed reference viewed: 6 (0 ULg)New acylnitroso compounds for the asymetric oxyamination of dienes; ; et al in Tetrahedron (1998), 54(35), 10537-10554 Detailed reference viewed: 4 (1 ULg)No-carrier-added asymmetric synthesis of alpha-methyl-alpha-amino acids labelled with fluorine-18; Lemaire, Christian ; Plenevaux, Alain et alin Tetrahedron (1997), 53(16), 5785-5796 Various [18F]fluoro aromatic α-methyl-L-amino acids 11 have been synthesized with high enantiomeric purity (ee > 97%). These new radiopharmaceuticals for Positron Emission Tomography (PET), potential ... [more ▼] Various [18F]fluoro aromatic α-methyl-L-amino acids 11 have been synthesized with high enantiomeric purity (ee > 97%). These new radiopharmaceuticals for Positron Emission Tomography (PET), potential inhibitors of enzymatic functions, were regiospecifically labelled by nucleophilic substitution on trimethylammoniumbenzaldehyde triflate precursors 9. The [18F]fluoro aromatic aldehydes 12 obtained were easily converted to the corresponding [18F]fluorobenzyl halides [13 (X = 1)]. After alkylation of the lithium enolate of (2S,5S)-l-tert-Boc-2-tert-butyl-3,5-dimethyl-imidazolidin-4-one 2, the adducts were cleaved to give, after HPLC purification, various [18F]fluoro-α-methyl amino acid analogs with radiochemical yields of 10% (End of Bombardment, EOB) after a synthesis time of 120 min. The corresponding [19F]fluorinated amino acids 4 and [19F]fluoro intermediates were also prepared. [less ▲] Detailed reference viewed: 16 (2 ULg)Combined enzymatic synthesis of nucleotide (deoxy) sugars from sucrose and nucleoside monophosphatesZervosen, Astrid ; ; et alin Tetrahedron (1996), 52(7), 2395-2404 Abstract: The synthesis of NDP-glucose 3a-d (N= A, C, U, dU) with sucrose synthase B was combined with the enzymatic synthesis of nucleoside diphosphates 2a-d from their corresponding nucleoside ... [more ▼] Abstract: The synthesis of NDP-glucose 3a-d (N= A, C, U, dU) with sucrose synthase B was combined with the enzymatic synthesis of nucleoside diphosphates 2a-d from their corresponding nucleoside monophosphates la-d by different kinases A. Further combination with recombinant dTDP-glucose 4,6-dehydratase D enabled us to synthesize dUDP-6-deoxy-alpha-D-xylo-4-hexulose 5 from ld on a preparative scale. By using the repetitive batch technique the enzymatic syntheses of nucleotide (deoxy) sugars 3a-d, 5 could be realized on a 0.1 - 0.5 g scale. [less ▲] Detailed reference viewed: 20 (5 ULg)Synthesis ans structural studies of a new class of heterocyclic compounds: 1,2,4-pyridothiadiazine 1,1-dioxides, pyridyl analogues of 1,2,4-benzothiadiazine 1,1-dioxidesDe Tullio, Pascal ; Pirotte, Bernard ; et alin Tetrahedron (1995), 51 Detailed reference viewed: 3 (1 ULg)Stereoselective synthesis of methyl (1R) trans- and (1R) cis-hemicaronaldehydes from natural tartaric acid : application to the synthesis of s-bioallethrin and deltamethrin insecticides; ; et al in Tetrahedron (1989), 45(10), 3039-3052 Detailed reference viewed: 21 (2 ULg) |
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