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Enumeration	Reference	Cover	Find
1.	Ankner, Tobias, 1976, et al. (author) SmI2/H2O/amine promoted reductive cleavage of benzyl-heteroatom bonds: optimization and mechanism 2009 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 65:52, s. 10856-10862 Journal article (peer-reviewed)
2.	Arvela, Riina K, et al. (author) Automated batch scale-up of microwave-promoted Suzuki and Heck coupling reactions in water using ultra-low catalyst concentrations 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 61:39, s. 9349-9355 Journal article (peer-reviewed)abstract Representative Suzuki and Heck couplings in water using ultra-low catalyst concentrations have been scaled-up using an automated batch stop-flow microwave apparatus. Our scale-up methodology shows proof of concept and is easy, fast and cheap to run.
3.	Bartoszewicz, Agnieszka, et al. (author) Iodine-promoted silylation of alcohols with silyl chlorides. Synthetic and mechanistic studies 2008 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 64:37, s. 8843-8850 Journal article (peer-reviewed)
4.	Bergh, Anders, et al. (author) Cobalt-mediated solid phase synthesis of 3-O-alkynylbenzyl galactosides and their evaluation as galectin inhibitors 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:35, s. 8309-8317 Journal article (peer-reviewed)abstract Methyl beta-D-galactoside was converted to the corresponding 3,4-O-stannylene acetal, which was selectively benzylated with 3-iodobenzyl bromide and coupled to a polymer-bound propargylic ether via a Sonogashira reaction. The polymer-bound carbohydrate substrate was cleaved from the resin with different carbon nucleophiles in a cobalt-mediated Nicholas reaction. The product 3-O-alkynylbenzyl galactosides were screened towards galectin-1, -3, -7, -8N and -9N in a competitive fluorescence polarisation assay. Particularly potent inhibitors were identified against galectin-7 with affinity enhancements up to one order of magnitude due to the 3-O-alkynylbenzyl moiety. (c) 2006 Elsevier Ltd. All rights reserved.
5.	Billing, Johan, et al. (author) Cyclic peptides containing a δ-sugar amino acid—synthesis and evaluation as artificial receptors 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 61:4, s. 863-874 Journal article (peer-reviewed)abstract An Fmoc-protected δ-sugar amino acid, prepared by oxidation of a glucosamine derivative, was coupled to three different tripeptide tert-butyl esters (H-Tyr-Tyr-Tyr-OtBu, H-Tyr-Glu(OBzl)-Tyr-OtBu and H-Tyr-Arg(Mtr)-Tyr-OtBu) and the resulting sugar amino acid/amino acid hybrids were transformed into dimers that were subsequently cyclized to give three C2-symmetric macrocycles. The macrocycles were deprotected and their binding properties towards p-nitrophenyl glycosides, nucleotides, and purines were examined. Of the ligands screened, only some of the purines showed weak, but significant, binding.
6.	Bjelosevic, Haris, et al. (author) Synthesis and structural characterisation of novel platinum-based drug candidates with extended functionality by incorporation of bis(diphenylphosphino)ferrocene units as metal chelators 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:18, s. 4519-4527 Journal article (peer-reviewed)abstract Among the metal-based anticancer drugs, cisplatin (cis-diaminedichloroplatinum(II)) is the most widely used species in therapy. Despite its clinical success, cisplatin still suffers in generating resistance, as well as being highly toxic due to poor selectivity between healthy and sick cells. By molecular design it ought to be possible to generate new cis-platinum compounds with increased selectivity and improved cellular behaviour. In this paper, we report a synthetic pathway for construction of derivatives of 1,1'-bis(diphenylphosphino)-ferrocene, together with their corresponding cis-platinum compounds with the aim testing them for their interaction capacity with respect to various DNA models. We also report a synthetic route for a nucleoside-based cis-platinum compound containing a bidentate ferrocenylphosphine derivative connected through a succinamic-based linker to the 5-position of the heterocyclic moiety of uridine. Our preliminary kinetic investigation of 5-{N-[1-[1',2-bis(diphenylphosphino)ferrocenyl]ethyl]1-N'-[prop-2-yn-3-y l]succinamide} uridinedichloroplatinum(II) showed that this compound reacted faster with the phosphorothioate containing oligonucleotides d(T(6)p(S)T-6), with an observed first-order rate constant k(obs) = (1.4 +/- 0.1) X 10(-4) s(-1), compared with the G-N7 target in d(T(7)GGT(7)), for which the observed first-order rate constant is k(obs) = (7.2 +/- 0.5) X 10(-4) s(-1). (c) 2006 Elsevier Ltd. All rights reserved.
7.	Blomberg, David, et al. (author) Synthesis of a β-strand mimetic based on a pyridine scaffold 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 62:47, s. 10937-10944 Journal article (peer-reviewed)abstract A synthetic route to a 2,4-disubstituted pyridine as a potential β-strand mimetic has been developed and applied in the synthesis of a tripeptidomimetic of Leu-Gly-Gly. The pyridine scaffold replaces the central glycine, and is substituted with analogues of leucine and glycine in positions 4 and 2, respectively. 2-Fluoro-4-iodopyridine was chosen as the functionalized scaffold and was substituted with protected leucinal in position 4 via a Grignard exchange reaction using iso-propyl magnesium chloride. The glycine moiety was introduced in position 2 via a nucleophilic aromatic substitution reaction (SNAr) facilitated by microwave irradiation. The synthetic sequence involved 12 steps with an overall yield of 7%.
8.	Bohman, Björn, et al. (author) Synthesis of all four stereoisomers of 5-hydroxy-4-methyl-3-heptanone using plants and oyster mushrooms 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:42, s. 8697-8701 Journal article (peer-reviewed)abstract All four possible stereoisomers of 5-hydroxy-4-methyl-3-heptanone were synthesized from common achiral reagents using fast, straightforward organic synthesis, including the use of whole tissue of Daucus carota, Solanum melongena, and Pleurotus ostreatus.
9.	Cotton, Hanna K., et al. (author) Screening of Ligands in the Asymmetric Metallocenethiolatocopper(I)-Catalyzed Allylic Substitution with Grignard Reagents 2006 In: Tetrahedron. - : Elsevier Ltd. - 0040-4020 .- 1464-5416. ; 62:24, s. 5632-5640 Journal article (peer-reviewed)abstract Screening of metallocenethiolate ligands for copper(I)-catalyzed substitution of allylic acetates with Grignard reagents has been carried out. The previously used ligand, lithium (R,Sp)-2-(1-dimethylaminoethyl)ferrocenylthiolate (4a), possessing both central and planar chirality, was the starting point for the screening. It was found that the diastereomeric ligand lithium (R,Rp)-2-(1-dimethylaminoethyl)ferrocenylthiolate (4b) exhibiting reversed planar chirality gave increased enantioselectivity in the allylic substitution, at least when cinnamyl acetate was used as a substrate. The ruthenocene-based ligand lithium (R,Sp)-2-(1-dimethylaminoethyl)ruthenocenylthiolate (4c) gave an enhanced reaction rate, but lower chiral induction. The use of disulfide bis[(R,Sp)-2-(1-dimethylaminoethyl)ferrocenyl]disulfide (7a) as a ligand precursor worked well but resulted in lower enantioselectivity.
10.	Cribiù, Riccardo, et al. (author) On the synthesis of vinyl and phenyl C-furanosides by stereospecific debenzylative cycloetherification 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:10, s. 2022-2031 Journal article (peer-reviewed)
11.	Das, AK, et al. (author) The role of protecting groups in the formation of organogels through a nano-fibrillar network formed by self-assembling terminally protected tripeptides 2007 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 63:31, s. 7432-7442 Journal article (other academic/artistic)
12.	de la Parra, Veronica, et al. (author) Cytotoxic terpenoids from Dasyscyphus niveus 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:8, s. 1828-1832 Journal article (peer-reviewed)abstract Three novel tetracyclic terpenoids, of which two possess potent cytotoxic activities towards various mammalian cell lines, were isolated front extracts of the fermentation broth of the ascomycete Dasayscyphus niveus. The structures of the compounds, named dasyscyphins A-C, were determined with spectroscopic techniques. (c) 2005 Elsevier Ltd. All rights reserved.
13.	Eklöf, Anders M, et al. (author) Effects of Substituents and Counterions on the Structures of Silenolates : A Computational Investigation 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:28, s. 5521-5526 Journal article (peer-reviewed)abstract The structures and charge distributions of substituted silenolates [H2SiC(=O)X](-) (X-H, SiH3, Me, t-Bu, OMe, NMe2; group A), [Y2SiC(=O)H](-) (Y=H, F, Me, Ph, SiH3, SiMe3; group B), and [Y2SiC(=O)X](-) (Y=Me, X=t-Bu, and Y=SiMe3; X=t-Bu, OMe, NMe2; group C) were examined through density functional theory calculations. The effects of the solvated counterion (K+, Li+, or MgCl+) and coordination site (O or Si) on the properties of group C silenolates were also Studied. The variation in the degree of pi-conjugative reverse SiC bond polarization, Sigma Phi(RP)(pi) calculated by natural resonance theory, was determined. The Sigma Phi(RP)(pi) correlated with r(SiC) for both group A and B silenolates, and the correlation between Sigma Phi(RP)(pi) and the Sum of valence angles at Si, Sigma alpha(Si), was good for group A but poor for group B due to strong influence of the inductive effect. The SiC charge difference correlated well with Sigma Phi(RP)(pi) for group A, but not for group B, again an effect of inductive substituent effects. The group C silenolates were Coordinated to Li(THF)(3)(+), MgCl(THF)(4)(+), and K(THF)(5)(+) either via the O or Si atom. The coordination energies show that coordination to the hard O is preferred for Li+ and MgCl+, but the K+ ion coordinated simultaneously to Si and O. Coordination of the solvated metal ion to O resulted in shorter SiC bond length, an increased Sigma alpha(Si) value, and lower Delta q(SiC) when compared to the naked silenolate. Choice Of counterion and substituent provides a means to extensively vary the properties of silenolates such as their reactivity.
14.	Ellervik, Ulf, et al. (author) 2-Bromoethyl glycosides for synthesis of glycoconjugates on solid support 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 61:9, s. 2421-2429 Journal article (peer-reviewed)abstract 2-Bromoethyl glycosides can easily and in high yields be transformed into sulfones by treatment with a suitable thiol followed by oxidation with mCPBA. The observation that the so formed sulfones were cleaved by treatment with NaOMe/MeOH was used to design a new safety catch linker for synthesis of glycoconjugates on solid support. (C) 2005 Elsevier Ltd. All rights reserved.
15.	Engqvist, Robert, et al. (author) Reduction of indolo[2,3-b]quinoxalines 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 61:18, s. 4495-4500 Journal article (peer-reviewed)abstract Reduction of indolo[2,3-b]quinoxalines with zinc in the presence of an anhydride gave N,N-diacyl trapped 6,11-dihydroindolo[2,3-b]quinoxalines in 43-92% yields. When the reduction with zinc was performed in TFA/TFAA, an unexpected ring opened product was isolated in 49% yield. The structure of this product could be identified as 1,2-dihydro-1-trifluoroacetyl-3-[(2-trifluoroacetylamino)phenyl]quinoxal ine.
16.	Gao, Yan, et al. (author) Synthesis and characterization of manganese and copper corrole xanthene complexes as catalysts for water oxidation 2007 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 63:9, s. 1987-1994 Journal article (peer-reviewed)abstract Two corrole xanthene ligands and four corresponding Mn-IV and Cu-III complexes have been synthesized and spectroscopically characterized. This kind of complexes, comprising of xanthene and corrole linked by an amide bond, were designed as bio-inspired models for the oxygen evolving complex (OEC) in Photosystem II. We find that both manganese complexes 4a and 5a have efficiency on catalyzing oxygen evolution at low potential (about 0.80 V) by electrochemical method, which is a significant progress in the study of dioxygen formation.
17.	Jam, Fariba, 1967, et al. (author) Microwave assisted synthesis of spiro-2,5-diketopiperazines 2007 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 63, s. 9881-9889 Journal article (peer-reviewed)abstract A general and efficient method for the synthesis of spiro-2,5-diketopiperazines (spiro-DKPs) is described. Cyclization of Boc-protected dipeptides containing spiro-amino acids by microwave assisted heating in water furnished the corresponding spiro-DKPs. The spiro-amino acids were prepared by combining stereoselective alkylation reactions using the Schöllkopf methodology for amino acid construction with Grubbs ring-closing metathesis (RCM) methodology using ruthenium complexes. The RCM reactions and all subsequent transformations to the spiro-DKPs were run with microwave assisted heating, resulting in high yields and short reaction times for all steps.
18.	Janosik, Tomasz, et al. (author) Efficient sulfonation of 1-phenylsulfonyl-1H-pyrroles and 1-phenylsulfonyl-1H-indoles using chlorosulfonic acid in acetonitrile 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 62:8, s. 1699-1707 Journal article (peer-reviewed)abstract The sulfonation of various 1-phenylsulfonyl-1H-pyrroles and 1-phenylsulfonyl-1H-indoles using chlorosulfonic acid in acetonitrile has been studied, leading to the development of a clean and operationally simple protocol allowing direct synthesis of the corresponding 1-phenylsulfonyl-1H-pyrrole-3-sulfonyl chlorides and 1-phenylsulfonyl-1H-indole-3-sulfonyl chlorides, respectively, both of which may be easily converted to various sulfonamide derivatives by treatment with nitrogen nucleophiles. Efficient and selective removal of the phenylsulfonyl- or tosyl groups in the sulfonamide series may be achieved under mild conditions.
19.	Janosik, T, et al. (author) Recent progress in the chemistry and applications of indolocarbazoles 2008 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 64:39, s. 9159-9180 Research review (other academic/artistic)
20.	Johnson, Ann-Louise, et al. (author) Synthetic approaches towards an indole alkaloid isolated from the marine sponge Halichondria melanodocia 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 62:47, s. 10815-10820 Journal article (peer-reviewed)abstract The exocyclic analogue of the indole alkaloid isolated from the marine sponge Halichondria melanodocia has been prepared via olefination of a phosphonoester derived from 3-(2-bromoacyl)indole. The formation of an unexpected indolylazepine is also discussed.
21.	Johnsson, Richard, et al. (author) Mild and efficient direct aromatic iodination 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 61:49, s. 11657-11663 Journal article (peer-reviewed)abstract Aryl iodides are important synthetic intermediates that can be transformed into tritium labelled compounds by metal-mediated hydrodehalogenation and also react in a number of important synthetic transformations. We present ICI/ln(OTf)(3) as a new reagent combination for mild iodination, suitable for acid-sensitive substrates such as carbohydrates. (c) 2005 Elsevier Ltd. All rights reserved.
22.	Kalek, Marcin, et al. (author) Efficient synthesis of mono-and diarylphosphinic acids : a microwave-assisted palladium-catalyzed cross-coupling of aryl halides with phosphinate 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:50, s. 10406-10412 Journal article (peer-reviewed)abstract A general, efficient method for the microwave-assisted synthesis of mono- and diarylphosphinic acids from anilinium phosphinate and aryl halides, using Pd(0) and Xantphos as a supporting ligand, was developed.
23.	Lagerlund, Olof, et al. (author) Aminocarbonylations of Alkenyl Phosphates, Chlorides, Bromides and Triflates with Mo(CO)6 as a Solid CO source 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:36, s. 7646-7652 Journal article (peer-reviewed)abstract Palladium-catalyzed aminocarbonylations of alkenyl chlorides, bromides, and triflates were investigated using Mo(CO)6 as a solid carbon monoxide source. The reactions afforded moderate to good yields producing a wide variety of acrylamides after 20 minutes of microwave irradiation. In addition, the aminocarbonylation reaction was, for the first time, expanded to include alkenyl phosphates as starting materials.
24.	Lindquist, Charlotta, et al. (author) Parallel synthesis of an indole-based library via an iterativeMannich reaction sequence 2006 In: Tetrahedron. - : Elsevier Ltd.. - 0040-4020 .- 1464-5416. ; 62:14, s. 3439-3445 Journal article (peer-reviewed)abstract A library of 1,3-disubstituted indoles has been prepared via an iterative Mannich reaction sequence. The first Mannich reaction with secondary amines and formaldehyde preferentially yields 3-aminomethyl indoles, while the second Mannich reaction introduces an additional aminomethyl group at the N1-position of the indole ring. A library of 25 substituted indoles has thus been prepared in moderate to good yields with purity.
25.	Liu, X. E., et al. (author) A novel ruthenium(II) tris(bipyridine)-zinc porphyrin-rhenium carbonyl triad : synthesis and optical properties 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 62:15, s. 3674-3680 Journal article (peer-reviewed)abstract A novel ruthenium(II) tris(bipyridine)-zinc porphyrin-rhenium carbonyl triads and its free base porphyrin derivative were synthesized and characterized by H-1, C-13 NMR, UV-vis, mass-spectrometry and elemental analysis. The redox potentials of the two Compounds were measured and compared to their corresponding reference complexes. The fluorescence and transient absorption spectra of the two complexes revealed the features of two different pathways for possible photoinduced intramolectular electron transfer or energy transfer in the triads.
26.	Liu, X., et al. (author) Synthesis, characterization and some properties of amide-linked porphyrin-ruthenium(II) tris(bipyridine) complexes 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 61:23, s. 5655-5662 Journal article (peer-reviewed)abstract A new molecular dyad, comprised of a zinc-porphyrin and a ruthenium(II) tris(bipyridine) complex linked through an amide bond has been synthesized and characterized by H-1, C-13 NMR, UV-vis, mass-spectrometry and elemental analysis. The electrochemistry as well as the steady-state emission properties were investigated. The redox behavior of the dyad exhibits a favorable reversible characteristic. Substantial quenching of porphyrin emission was found when the Q hand of 5 and 5-Zn was selectively photoexcited. This observation suggests a quenching mechanism with possible intramolecular electron transfer or energy transfer between the Ru(bpy)(3) moiety and the porphyrin free-base or Zn porphyrin moieties.
27.	Liu, Xien, et al. (author) Synthesis, electrochemical, and photophysical studies of multicomponent systems based on porphyrin and ruthenium(II) polypyridine complexes 2007 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 63:37, s. 9195-9205 Journal article (peer-reviewed)abstract Two ruthenium tris-bipyridine functionalized porphyrins 4, 8 and their Zn derivatives 4-Zn, 8-Zn were designed, synthesized, and characterized. The redox potentials of these complexes as well as their corresponding monomeric reference porphyrin and ruthenium bipyridine complexes were also measured for comparison. Primary dynamic studies on the electron injection and backing recombination between these complexes and TiO2 nanoparticles were carried out by means of transient absorption spectroscopy. The results indicate that a long-lived charge separation state was obtained in these assemblies.
28.	Naeslund, Charlotta, et al. (author) Enantioselective synthesis of m-carboranylalanine, a boron-rich analogue of phenylalanine 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 61, s. 1181-1186 Journal article (peer-reviewed)abstract The enantiomers of the highly lipophilic a-amino acid m-carboranyl-alanine [3-(1.7-dicarba-closo-dodecaborane(12)-1-yl)-2-aminopropanoic acid], a carborane containing analogue of phenylalanine, have been synthesised via hydroxyamination of the N-acyl derivative formed from 3-(m-carboranyl)propionoic acid [3-(1.7-dicarba-closo-dodeca-borane(12)-1-yl)-2-propanoic acid] and Oppolzer's camphor sultam. The enantiomeric excess of both enantiomers of the amino acid was >98%. (S)-Configuration was assigned to the (+)-enantiomer (ch3Oh, 589 nm).
29.	Nakhai, A, et al. (author) Synthesis of hydrogenated indazole derivatives starting with alpha,beta-unsaturated ketones and hydrazine derivatives 2009 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 65:11, s. 2298-2306 Journal article (other academic/artistic)
30.	O'Mahony, Gavin, et al. (author) A practical synthesis of 2′-aminoacylamino-2′-deoxyadenosines 2007 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 63:29, s. 6901-6908 Journal article (peer-reviewed)abstract A practical and efficient synthesis of 2′-aminoacylamino-2′-deoxyadenosine derivatives is reported. EDCI/HOBt-mediated coupling of a 3′,5′-diprotected 2′-amino-2′-deoxyadenosine derivative to various N-Cbz-l-amino acid derivatives followed by global deprotection affords analytically pure 2′-aminoacylamino-2′-deoxyadenosine derivatives without the necessity for preparative HPLC purification. These compounds are non-hydrolysable isosteres of 2′-aminoacyladenosines, which are of use in X-ray studies for the elucidation of the editing mechanism of various tRNA synthetases.
31.	O'Mahony, Gavin, et al. (author) Synthesis and photophysical properties of novel cyclonucleosides—substituent effects on fluorescence emission 2008 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 64:30-31, s. 7151-7158 Journal article (peer-reviewed)abstract An intramolecular [3+2]-cycloaddition between an azide and a disubstituted alkyne afforded a number of novel adenosine-derived cyclonucleosides, which exhibited fluorescence in the visible range. The synthesis and photophysical properties of these potential fluorescent probes are described.
32.	Pemberton, Nils, et al. (author) Synthesis and evaluation of dihydroimidazolo and dihydrooxazolo ring-fused 2-pyridones - Targeting pilus biogenesis in uropathogenic bacteria 2008 In: Tetrahedron. - : Elsevier. - 0040-4020 .- 1464-5416. ; 64:40, s. 9368-9376 Journal article (peer-reviewed)abstract Dihydrothiazolo ring-fused 2-pyridones have previously been shown to inhibit pilus assembly in uropathogenic Escherichia coli. Methods have now been developed to synthesize both dihydroimidazolo and dihydrooxazolo ring-fused 2-pyridones. To obtain the nitrogen analogs, Cbz-protected imidazolines were reacted with an acyl-Meldrum's acid derivative under acidic conditions. To prepare the oxygen analogs, a one-pot procedure was developed that allowed synthesis of dihydrooxazolo ring-fused 2-pyridones starting from acylated serine derivatives. After hydrolysis to their corresponding carboxylic acids and lithium carboxylates, biological evaluation revealed that the sulfur could be replaced by an oxygen atom and still maintains the ability to inhibit pilus assembly in uropathogenic E. coli. However, introducing a secondary amine instead of oxygen resulted in a substantial decrease in biological activity.
33.	Petersson, M. J., et al. (author) Unexpected regiospecific reactivity of a substituted phthalic anhydride 2007 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 63:6, s. 1395-1401 Journal article (peer-reviewed)abstract Regioselective nucleophilic addition at C1 of anhydride 7 by a range of nucleophiles occurs to produce amide, ester and thioester derivatives 8-15 (60-99%). The increased electrophilic reactivity of the C I carbonyl group of anhydride 7 is supported by a competition experiment with phthalic anhydride. Unexpected formation of lactams 18 and 19 from amides 12 and 13 was shown to proceed via the lactamols 16 and 17 and could be controlled by the reaction conditions. The solid-state structure of 19 is reported. (c) 2006 Published by Elsevier Ltd.
34.	Rehn, Stanley, et al. (author) The reaction between 3-aminocrotonates and oxindole-3-ylidene derivatives : synthesis of highly substituted pyrroles 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 61:12, s. 3115-3123 Journal article (peer-reviewed)abstract The reaction between 3-aminocrotonates and 3-acetonylideneoxindole in refluxing toluene resulted in 2-pyrrolo-3 '-yloxindoles in high yields (around 90%). At room temperature the 2-pyrrolo-3 '-yioxindoles exists as keto-enol tautomers. Treatment with POCl3 yielded the 2-chloro-3-pyrrolyl indole, which gave the pyrrolo annulated indolopyran-2-one upon basic hydrolysis of 2-chloro-3-pyrrolyl indole methyl ester.
35.	Risberg, E., et al. (author) Lewis acid-catalyzed asymmetric radical additions of trialkyl-boranes to (1R,2S,5R)-2-(1-methyl-1-phenylethyl)-5-methylcyclohexyl-2H-azirine-3-carboxylate 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 61:35, s. 8443-8450 Journal article (peer-reviewed)abstract The asymmetric addition of alkyl radicals to (IR,2S,5R)-2-(l-methyl-l-phenylethyl)-5-methylcyclohexyl-2H-azirine-3-carboxylate (1) yielding the corresponding 2-alkylaziridine-2-carboxylates has been investigated. High diastereoselectivities and good yields were obtained in the addition of primary alkyl radicals to azirine 1, while secondary radicals gave a lower dr. The influence of Lewis acids was also investigated, 10 mol% of CuCl were found to increase the dr.
36.	Russo, Francesco, et al. (author) Synthesis and evaluation of a new class of tertiary alcohol based BACE-1 inhibitors 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:48, s. 10047-10059 Journal article (peer-reviewed)abstract BACE-1 has emerged as one of the best characterized targets for future Alzheimer therapy. In accordance with the successful identification of masked inhibitors of HIV-1 protease, we envisioned that tert-alcohol containing transition-state mimicking structures would also be worthwhile evaluating as BACE-1 inhibitors. Twelve novel inhibitors were prepared via synthetic routes using epoxyalcohol derivates as key intermediates. The best synthesized tert-hydroxy inhibitor exhibited a BACE-1 IC50 value of 0.38 mu M.
37.	Sabbani, Sunil, et al. (author) Diastereoselective Schenck Ene Reaction of Singlet Oxygen with Chiral AllylicAlcohols; Access to Enantiomerically Pure 1,2,4-Trioxanes 2009 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 65:41, s. 8531-8537 Journal article (peer-reviewed)abstract A series of antimalarial chiral 1,2,4-trioxanes (1–8) were synthesised in high enantiomeric purities. Enantioselective addition of R2Zn reagent to 3-methyl-2-butenal catalysed by (+)-MIB or (−)-MIB yielded both the enantiomers of the chiral allylic alcohols 9–11 (90–98% ee), which were subjected to diastereoselective photooxygenation in the presence of tetraphenylporphine (TPP) to obtain (R,R)-threo- or (S,S)-threo-β-hydroperoxy alcohols (12–14). Reaction of β-hydroperoxy alcohols (12–14) with different cyclic ketones produced optically active trioxanes 1–8.
38.	Shirani, H, et al. (author) New syntheses of unsymmetrical thiepins and their selenium analogues 2009 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 65:40, s. 8350-8353 Journal article (other academic/artistic)
39.	Svennebring, Andreas, et al. (author) A mechanistic study on modern palladium catalyst precursors as new gateways to Pd(0) in cationic Heck reactions 2008 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 64:8, s. 1808-1812 Journal article (peer-reviewed)abstract Electrospray ionization mass spectrometry (ESI-MS) was used as a means to directly identify catalytic cationic organopalladium species in ligand-controlled Heck reactions involving electron-rich olefins and different Pd-sources. In these high-temperature Heck arylations, the oxidative addition intermediates were observed as bidentate ligand chelated cationic aryl palladium species, suggesting that the used ligand attaches to the metal center at the very beginning of the catalytic cycle. This was also in agreement with the obtained regioisomeric profile of the isolated products. The investigation supports the standard Pd(0)/Pd(II) Heck mechanism and provides further insight regarding the conceivable composition of fundamental Pd(II) intermediates in an ongoing Heck reaction.
40.	Thornqvist, Viveca, et al. (author) Synthesis of novel spiro-cyclohexene bicyclo[2.2.2]octane derivatives 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:50, s. 11793-11800 Journal article (peer-reviewed)abstract A methodology for the synthesis of novel spiro-cyclohexene bicyclo [2.2.2] octane derivatives, including Claisen rearrangement and ring-closing metathesis (RCM) as key synthetic steps, is described. (c) 2006 Elsevier Ltd. All rights reserved.
41.	Tilliet, Mélanie, et al. (author) Convenient Preparation of Bifunctional Pybox Ligands 2008 In: Tetrahedron. - : Elsevier BV. - 0957-4166 .- 1362-511X .- 0040-4020. ; 64:44, s. 10244-10249 Journal article (peer-reviewed)abstract Starting from a common easily available pybox derivative, chiral ditopic ligands with pendant Lewis basic sites consisting of amine or phosphine oxide functions attached in the 4-positions of the oxazoline rings were prepared by simple synthetic procedures. From the same pybox derivative, a macrocyclic ligand containing a diaza-18-crown-6-ether ring linked via triazole groups was obtained employing 'click' chemistry.
42.	Trejos, Alejandro, et al. (author) Stereoselective Heck arylation of a functionalized cyclopentenyl ether using (S)-N-methyl-pyrrolidine as the stereochemical controller 2008 In: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 64:37, s. 8746-8751 Journal article (peer-reviewed)abstract The study of a series of palladium(0)-catalyzed C2-arylations of a 1-cyclopentenyl ether equipped with a chiral (S)-N-methyl-pyrrolidine auxiliary is reported. Stereoselective Heck monoarylations were performed using aryl iodides under classical heating conditions for 1.7-3.0 h at 80 degrees C and in one case using 30 min of microwave irradiation at 110 degrees C. To further explore the scope and nature of this stereoselective methodology, aryl bromides were also utilized as arylating agents, using 20 min of microwave processing at 120-130 degrees C. High to excellent diastereopurities (90-98% de) were obtained according to H-1 NMR and GC-MS analyses. The prolinol fragment apparently controlled the chastereoselectivity of the Heck reaction by presenting the arylpalladium species from the preferred side of the double bond. By X-ray structure diffraction analysis of an N-quaternized Heck product, the absolute configuration of the new stereocenter was established as (R), Supporting a Si-face migratory insertion.
43.	Tullberg, Marcus, 1974, et al. (author) Efficient synthesis of 2,5-diketopiperazines using microwave assisted heating 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:31, s. 7484-7491 Journal article (peer-reviewed)abstract In this study a general, efficient and environmentally benign solution phase synthesis of 2,5-diketopiperazines (DKPs) using microwave assisted heating in water is described. A series of 11 structurally different DKPs have been synthesized from dipeptide methyl esters. A range of common laboratory solvents have been tested as well as different reaction times and temperatures. Both classic thermal and microwave assisted heating have been investigated. Microwave assisted heating for 10 min using water as solvent proved, by far, to be the most efficient method of cyclization giving moderate to excellent yields (63-97%) of DKPs. In contrast to other published procedures, this method seems independent of the amino acid sequence. (c) 2006 Elsevier Ltd. All rights reserved.
44.	Valdivia, Carola, et al. (author) Diterpenoids from Coprinus heptemerus 2005 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 61:40, s. 9527-9532 Journal article (peer-reviewed)abstract Seven diterpenoids, isolated due to their ability to inhibit spore germination in the plant pathogenic fungus Magnaporthe grisea, were obtained from cultures of the basidiomycete Coprinus heptenlerus. The structures of the compounds, named heptemerones A-G, were determined with spectroscopic techniques. (c) 2005 Elsevier Ltd. All rights reserved.
45.	Wiktelius, Daniel, 1976, et al. (author) Peracid dependent stereoselectivity and functional group contribution to the stereocontrol of epoxidation of (E)-alkene dipeptide isosteres 2006 In: Tetrahedron. - : Elsevier BV. - 0040-4020. ; 62:15, s. 3600-3609 Journal article (peer-reviewed)abstract Twelve Boc-protected phenylaianyl-phenylalanine and phenylalanyl-glycine trans-vinyl isosteres were epoxidised with magnesium monoperoxyphtalate hcxahydrate (MMPP) and trifluoroperacetic acid, and the results have been compared with those from earlier studies on epoxidations with m-CPBA. The alkenes were synthesised in high yields with high E/Z-selectivities using either the Julia or Schlosser reactions. The formation of threo isomers was favoured in all epoxidation reactions except with CF3CO3H on substrates containing two allylic/homoallylic functional groups directing the peracid to opposite faces of the alkene. The switch to erythro selectivity observed with CF3CO3H is suggested to ernanate from coordination to the allylic ester functionalities via hydrogen bond donation from the peracid. The other peracid reagents seem to be preferentially coordinated to the allylic carbamate function. The contribution of individual functional groups to the stereopreference was also investigated. (c) 2006 Elsevier Ltd. All rights reserved.
46.	Yuan, ZhongQing, et al. (author) Synthesis of a beta-turn mimetic suitable for incorporation in the peptide hormone LHRH 2005 In: TETRAHEDRON. - : Elsevier BV. - 0040-4020. ; 61:21, s. 4901-9 Journal article (peer-reviewed)abstract LHRH is a decapeptide hormone which plays a central role in neuroendocrinology. Conformational studies have suggested that LHRH may adopt a beta-turn involving residues 5-8 when bound to its receptor. A beta-turn mimetic with side chains corresponding to those of a Tyr-Gly-Leu-Orn tetrapeptide has therefore been synthesized for incorporation at positions 5-8 in LHRH. In the turn mimetic, residues i and i + 1 are connected by a psi [CH2O] isostere instead of an amide bond, while a covalent ethylene bridge replaces the hydrogen bond which is often found between residues i and i+3 in beta-turns. The turn mimetic was assembled from three types of building blocks: an azido aldehyde, an Fmoc protected amino acid and a protected dipeptide amine.

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