SwePub - sökning: L773:0040 4039

Numrering	Referens	Omslagsbild	Hitta
1.	Baker, T. C., et al. (författare) Isolation, identification and synthesis of sex pheromone components of the carob moth, Ectomyelois ceratoniae 1989 Ingår i: Tetrahedron Letters. - 0040-4039. ; 30:22, s. 2901-2902 Tidskriftsartikel (refereegranskat)abstract The sex pheromone of females of the carob moth, Ectomyelois ceratoniae, was identified to be a mixture of (Z,E)-9,11,13-tetradecatrienal, (Z,E)-9,11-tetradecadienal and (Z)-9-tetradecenal in the ratio of 10:1:1. A synthetic blend proved to be attractive. GC/EAD + GC/MS investigations showed (Z,E)-9,11,13-tetradecatrienal, (Z,E)-9,11-tetradecadienal and (Z)-9-tetradecenal to be the sex pheromone of the carob moth. Blends of synthetic compounds are active.
2.	Bhattacharyya, Tapes, et al. (författare) An efficient and convergent route towards water-soluble, chiral and amphiphilic macrocycles 2001 Ingår i: Tetrahedron Letters. - 0040-4039. ; 42:15, s. 2873-2875 Tidskriftsartikel (refereegranskat)abstract A practical procedure for the synthesis of water-soluble, chiral and amphiphilic macrocyclic molecules is described. Acylation of p-xylylene diamine with Fmoc-protected glycine and aspartic acid, followed by removal of the Fmoc moiety afforded amino acid:p-xylene conjugates as free diamines. These diamines were converted to symmetrical and unsymmetrical macrocycles via stepwise urea formation using p-nitrophenyl chloroformate.
3.	Davidsson, A., et al. (författare) Polarised absorption spectra of benzene, naphtalene and anthracene obtained with a high sensitive linear dichroism technique 1972 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1873-3581. ; :30, s. 3093-3096 Tidskriftsartikel (refereegranskat)
4.	Ellervik, Ulf (författare) 9-Anthraldehyde acetals as protecting groups. 2003 Ingår i: Tetrahedron Letters. - 0040-4039. ; 44:11, s. 2279-2281 Tidskriftsartikel (refereegranskat)abstract Anthraldehyde acetals can be introduced regioselectively to carbohydrates in high yields. Advantages over conventional acetal protecting groups are increased crystallinity and strong absorbance and fluorescence which facilitate purification and reaction monitoring. The anthraldehyde acetals can be deprotected selectively in the presence of benzylidene acetals and can be cleaved regioselectively to yield 6-O-(9-anthracenyl)methyl ethers.
5.	Ellervik, Ulf, et al. (författare) Guanidine/Guanidinium Nitrate; a Mild and Selective O-Deacetylation Reagent that leaves the N-Troc Group Intact 1997 Ingår i: Tetrahedron Letters. - 0040-4039. ; 38:9, s. 1627-1628 Tidskriftsartikel (refereegranskat)
6.	Eriksson Bajtner, Johan, et al. (författare) Synthesis of podoscyphic acid 2002 Ingår i: Tetrahedron Letters. - 0040-4039. ; 43:5, s. 891-893 Tidskriftsartikel (refereegranskat)abstract Podoscyphic acid 1, a fungal metabolite inhibiting RNA-directed DNA polymerises, was synthesised in four steps starting from dodecanal. The concluding ester hydrolysis of 4 was not feasible with chemical reagents, only enzymatic hydrolysis was mild enough to release the highly reactive natural product in good yields. (C) 2002 Elsevier Science Ltd. All rights reserved.
7.	Grundberg, Hans, et al. (författare) Conversion of 2-(trimethylsilyl)ethyl sulfides into thioesters 1999 Ingår i: Tetrahedron Letters. - 0040-4039. ; 40:9, s. 1811-1814 Tidskriftsartikel (refereegranskat)abstract Treatment of 2-(trimethylsilyl)ethyl sulfides with a carboxylic acid chloride and AgBF4 in CH2Cl2 furnishes the corresponding thioesters in high yields and purities. The conversion of 2-(trimethylsilyl)ethyl sulfides into synthetically versatile thioesters allows such sulfides to be used as sulfhydryl protective groups, since such sulfides are easily prepared and are stable towards many reaction conditions encountered in organic syntheses.
8.	Jacobsson, Mårten, et al. (författare) Synthesis of naphthoxylosides on solid support 2002 Ingår i: Tetrahedron Letters. - 0040-4039. ; 43:37, s. 6549-6552 Tidskriftsartikel (refereegranskat)abstract In order to investigate the selective antiproliferative effects shown by 2-(6-hydroxynaphthyl)-beta-D-xylopyranoside the 14 possible beta-D-xylopyranosidic compounds were synthesized on solid support. An aminomethylated polystyrene resin was converted into an acid chloride resin and then esterified using dihydroxynaphthalene. The free hydroxy group was then xylosylated Under BF3.OEt2 mediated conditions. The xyloside was deprotected and simultaneously cleaved off the resin Using NaOMe/MeOH. Final purification using reverse phase HPLC gave the pure xylosides in 6-42% yield with Virtually no formation of alpha-xylosides. (C) 2002 Elsevier Science Ltd. All rights reserved.
9.	Kempe, Maria, et al. (författare) Receptor binding mimetics: a novel molecularly imprinted polymer 1995 Ingår i: Tetrahedron Letters. - 0040-4039. ; 36:20, s. 3563-3566 Tidskriftsartikel (refereegranskat)abstract A novel molecularly imprinted polymer was prepared by copolymerization of trimethylolpropane trimethacrylate (1) and methacrylic acid (3) in the presence of a dipeptide acting as the template. The recognition capability of the synthetic receptor-like binding sites produced in the polymer network for the peptide was demonstrated by using the polymer as a chiral stationary phase in HPLC. The polymer was superior to previously reported molecularly imprinted polymers in that unusually high racemic resolution and load capacity were demonstrated.
10.	Koch, T., et al. (författare) PNA-Peptide Chimerae 1995 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1873-3581. ; 36:38, s. 6933-6936 Tidskriftsartikel (refereegranskat)abstract Radioactive labelling of PNA has been performed try linking a peptide segment to the PNA which is substrate for protein kinase A. The enzymatic phosphorylation proceeds in almost quantitative yields.
11.	Ohlsson, Jörgen, et al. (författare) A galabiose-based two-dimensional scaffold for the synthesis of inhibitors targeting Pk- and P-antigen binding proteins. 2003 Ingår i: Tetrahedron Letters. - 0040-4039. ; 44:14, s. 2785-2787 Tidskriftsartikel (refereegranskat)abstract A disaccharide scaffold based on galabiose (Gal1–4Gal) was synthesized. Four different acceptors were evaluated in the -galactosylation and a relationship between the nucleophilicity, yield, and /-selectivity was found. The scaffold contains two orthogonal derivatisation sites, i.e. at O-2′ and the anomeric position, and as proof of concept, one derivatised galabioside was synthesized. Compounds based on this galabiose-scaffold are potential inhibitors of P- and Pk-antigen binding proteins.
12.	Olsson, Roger, et al. (författare) Is a hydrogen bonded carbene an intermediate in the organoaluminum-induced ring opening of pyranosides? 1997 Ingår i: Tetrahedron Letters. - 0040-4039. ; 38:32, s. 5701-5704 Tidskriftsartikel (refereegranskat)abstract Semiempirical and ab initio quantum chemical computations indicate that the intermediate formed prior to the selectivity-determining methyl transfer step in the reaction between glycosides and trimethylaluminum is a strongly hydrogen-bended equilibrium OH...C = O-H...C, which is proposed to be an important selectivity promoting factor in the alkyl transfer reaction.
13.	Quiroz-García, B, et al. (författare) Base-catalyzed intramolecular condensation of tokinolide B. 2003 Ingår i: Tetrahedron Letters. - 0040-4039. ; 44:12, s. 2509-2512 Tidskriftsartikel (refereegranskat)abstract The novel pentacyclic compound cyclotokinolide B was obtained from the natural phthalide tokinolide B under basic conditions, via the chemoselective -enol lactone opening followed by a Michael addition of the generated carbanion to the enone and subsequent equilibration. This result confirms that some dimeric phthalides undergo intramolecular cyclizations in basic media.
14.	Rehnberg, Nicola, et al. (författare) Diastereoselective conjugate addition of lithium methylcyanocuprate to the chiral isoprene units 2-(R)- and (S)-benzyloxy-2,5-dihydro-4-furancarboxaldehyde. Total synthesis of (-)- and (+)-botryodiplodin and (+)- and (-)-epibotryodiplodin. 1987 Ingår i: Tetrahedron Letters. - 0040-4039. ; 28:31, s. 3589-3592 Tidskriftsartikel (refereegranskat)abstract Conjugate addition of lithium methylcyanocuprate to the titlealdehydes proceeded with high diastereoselectivity (d.e. 94%). Methyl lithium 1,2-addition, followed by Swern oxidation of the resultingalcohols, gave benzyl botryodiplodin and benzyl epi-botryodiplodin.Hydrogenolysis of the benzyl groups gave the enantiomeric pairs ofbotryodiplodin 10r and 10s and epi-botryodiplodin (9r and 9s).
15.	Rehnberg, Nicola, et al. (författare) Total synthesis of the lignans (-)- and (+)-burseran, (-)-cubebin, and (-)-hinokinin by diastereoselective conjugate addition of benzyl anions to 2-(R) and (s)-benzyloxy-2,5-dihydro-4-(3,4-methylenedioxybenzoyl)furan 1988 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039. ; 29:29, s. 3599-3602 Tidskriftsartikel (refereegranskat)abstract 1,2-Addition of 3,4-methylenedioxymagnesium bromide to 2-(R) and (S)-benzyloxy-2,5-dihydro-4-furancarboxaldehyde, followed by oxidation, gave the title ketones (3r and 3s). Conjugate addition of the anions of 3,4,5-trimethoxy- and 3,4-methylenedioxybenzaldehyde diphenylthioacetal to 3r and 3s and Raney-nickel desulfurisation, followed by hydrogenolysis under various conditions, gave the title lignans. (-)-Burseran was prepared in >98% diastereomeric excess.
16.	Roncal, T, et al. (författare) Novel diterpenes with potent conidiation inducing activity 2002 Ingår i: Tetrahedron Letters. - 0040-4039. ; 43:38, s. 6799-6802 Tidskriftsartikel (refereegranskat)abstract The isolation and structure determination of conidiogenol and conidiogenone, tetracyclic diterpenes with a novel carbon skeleton, from extracts of the fermentation broth of Penicillium cyclopium is reported. Conidiogenol and conidiogenone are potent and selective inducers of conidiogenesis in P. cyclopium in liquid culture, and relay information about the environmental conditions to the producing organism. (C) 2002 Elsevier Science Ltd. All rights reserved.
17.	Sterner, Olov, et al. (författare) Velutinal esters of lactarius vellereus and L. Necator. The preparation of free velutinal. 1983 Ingår i: Tetrahedron Letters. - 0040-4039. ; 24:13, s. 1415-1418 Tidskriftsartikel (refereegranskat)abstract Esters of the pentacyclic sesquiterpene velutinal have been isolated from Lactarius species, and converted to the free alcohol by base-catalyzed transesterfication in EtOH/EtO-.
18.	Sundin, Anders, et al. (författare) Asymmetric diels-alder reaction between the chiral isoprene units 2-(r)-and (s)-benzyloxy-2,5-dihydro-4-furancarboxaldehyde and cyclopentadiene 1985 Ingår i: Tetrahedron Letters. - 0040-4039. ; 26:45, s. 5605-5608 Tidskriftsartikel (refereegranskat)abstract The title Diels-Alder reaction gave a mixture of enantiomerically pure adducts with complete norbornane-type monoterpene skeletons. The exo/endo ratio of the products changed from approximately 4:1 at 5° to 2:1 at 165°
19.	Bergman, J, et al. (författare) Formation of 3,3,5,7-tetranitrooxindole and 3,5,7-trinitroindazole by nitration of oxindole 1996 Ingår i: TETRAHEDRON LETTERS. - 0040-4039. ; 37:51, s. 9263-9266 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
20.	Bergman, J, et al. (författare) Formation of 6,13-dimethyl-5,12-diazachrysene by oxidative coupling of 2-methylindole followed by base-induced ring-expansion. 1998 Ingår i: TETRAHEDRON LETTERS. - 0040-4039. ; 39:23, s. 4119-4122 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
21.	BERGMAN, J, et al. (författare) REACTIONS OF INDOLE-3-ACETIC-ACID DERIVATIVES IN TRIFLUOROACETIC-ACID 1995 Ingår i: TETRAHEDRON LETTERS. - 0040-4039. ; 36:22, s. 3945-3948 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
22.	Bergman, Jan, et al. (författare) Synthesis of the indole alkaloid ellipticine 1977 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 18:52, s. 4663-4666 Tidskriftsartikel (refereegranskat)
23.	Bergman, J., et al. (författare) The structure of the lossen rearrangement product of 2-methyl-3-N-oxidoquinazoline-4-hydroxamic acid 1976 Ingår i: Tetrahedron Letters. - 0040-4039. ; 17:40, s. 3615-3616 Tidskriftsartikel (refereegranskat)
24.	Blid, Jan, et al. (författare) Lewis Acid Mediated [2,3]-Sigmatropic Rearrangement of Allylic Ammonium Ylides 2003 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 44:15, s. 3159-3162 Tidskriftsartikel (refereegranskat)abstract An investigation of the Lewis acid mediated [2,3]-sigmatropic rearrangement of allylic ammonium ylides has been conducted by employing various bases and boron Lewis acids. Using BBr3 together with the phosphazene base 6, various allylic amines could be rearranged in good yields with low to excellent diastereoselectivity.
25.	Brånalt, J, et al. (författare) A convenient synthesis of 1-(S)-[1'-(S)-(t-butyloxycarbonylamino)-2'-phenylethyl]oxirane : a useful building block in the synthesis of HIV protease inhibitors 1997 Ingår i: Tetrahedron Letters. - : Elsevier. - 0040-4039 .- 1359-8562. ; 38:19, s. 3483-3486 Tidskriftsartikel (refereegranskat)
26.	Bäckvall, Jan-Erling, et al. (författare) Evidence for (π-allyl)palladium(II)(quinone) complexes in the palladium-catalyzed 1,4-diacetoxylation of conjugated dienes 1988 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 29:18, s. 2243-2246 Tidskriftsartikel (refereegranskat)abstract Evidence for a coordination of p-benzoquinone to palladium in [4-acetoxy-η3-(1,2,3)-cyclohexenyl]-palladium(II) complexes was provided by changes of the 1H NMR chemical shift values of the π-allyl protons and a decrease of the spin-lattice relaxation time constant for the p-benzoquinone protons. The intermediate (π-allyl)palladium(benzoquinone) complexes previously postulated in palladium-catalyzed 1,4-oxidations of 1,3-dienes were detected by NMR spectroscopy.
27.	Hortala, L., et al. (författare) Acyl transfer of 8-acetoxy-2-oxazolinylquinoline assisted by hydrogen bonding formation 2002 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 43:6, s. 1027-1029 Tidskriftsartikel (refereegranskat)abstract A significant acceleration of acyl transfer has been achieved on 8-acetoxy-2-oxazolinylquinoline in the presence of benzylamine. Comparison of the aminolysis by the new acylating reagent with that of 8-acetoxyquinoline and 8-acetoxyquinoline-2-carbonitrile has been carried out. The results of these experiments suggest that the proximity of a supplementary basic atom to the ester group increases the participation effect of the basic site mainly by formation of a possible second hydrogen bond. The association constant of benzylamine into the basic cavity of 8-methoxy-2-oxazolinylquinoline (K-d = 80 M-1) has been measured by H-1 NMR titration experiments.
28.	Högberg, Hans-Erik, et al. (författare) Formation of hemiacetal esters in lipase-catalysed reactions of vinyl esters with hindered secondary alcohols 2000 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 41:17, s. 3193-3196 Tidskriftsartikel (refereegranskat)
29.	Johansson, Tommy, et al. (författare) 2-Pyridylphosphonates : A New type of Modification for Nucleotide Analogues 2001 Ingår i: Tetrahedron Letters. - : Elsevier. - 0040-4039. ; 42:11, s. 2217-2220 Tidskriftsartikel (refereegranskat)abstract Suitably protected dithymidine H-phosphonates afforded the corresponding dinucleoside 2-pyridylphosphonates upon treatment with N-methoxypyridinium tosylate in acetonitrile in the presence of 1,8-diazabicylo[5.4.0]undec-7-ene (DBU). The reaction was rapid (ca. 5 min), practically quantitative and proceeded stereospecifically, most likely with retention of configuration at the phosphorus centre. A simple and efficient protocol for the preparation of a new type of oligonucleotide analogue bearing a 2-pyridylphosphonate internucleotide linkage was developed
30.	Langlet, Abraham, et al. (författare) Synthesis and reaction of 5,5-dinitrobarbituric acid 2000 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 41:12, s. 2011-2013 Tidskriftsartikel (refereegranskat)abstract Nitration of barbituric acid at 40°C gave the previously unknown 5,5- dinitrobarbituric acid (3), which readily underwent hydrolysis to dinitroacetylurea (5), which in turn could be hydrolysed in basic media to the potassium salt of dinitromethane. Alloxane was prepared in a one step procedure by thermal decomposition of 5,5-dinitrobarbituric acid in hot acetic acid.
31.	Larhed, M, et al. (författare) Rapid microwave-assisted Suzuki coupling on solid-phase 1996 Ingår i: Tetrahedron Letters. - UNIV UPPSALA,CTR BIOMED,DEPT ORGAN PHARMACEUT CHEM,S-75123 UPPSALA,SWEDEN. UNIV UPPSALA,CTR BIOMED,DEPT MED & PHYSIOL CHEM,S-75123 UPPSALA,SWEDEN. : Elsevier BV. - 0040-4039 .- 1359-8562. ; 37:45, s. 8219-8222 Tidskriftsartikel (refereegranskat)abstract Microwave-assisted palladium-catalysed coupling of aryl and heteroaryl boronic acids with iodo- and bromo-substituted benzoic acids, anchored to TentaGel S RAM, provided high isolated yields of coupled products after a reaction time of 3.8 minutes (45 W). Copyright (C) 1996 Elsevier Science Ltd.
32.	Lindström, Ulf M., et al. (författare) Microwave-assisted aminolysis of vinylepoxides 1999 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 40:52, s. 9273-9276 Tidskriftsartikel (refereegranskat)abstract Di- and trisubstituted vinyl epoxides in NH4OH were subjected to microwave irradn. affording the corresponding vicinal amino alcs. in high yields. The reaction is stereospecific and highly regioselective for addn. at the allylic carbon. [on SciFinder(R)]
33.	Löfström, Claes M.G., et al. (författare) BF3-induced rearrangement of aziridinocyclopropanes derived from 2-phenylsulfonyl-1,3-dienes : A new approach to the tropane alkaloid skeleton 1996 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 37:19, s. 3371-3374 Tidskriftsartikel (refereegranskat)abstract Five N-substituted derivatives of 1,2-methylene-3,4-aziridino 2-phenylsulfonyl cycloalkanes (3a-e) were prepared from their corresponding epoxy cyclopropanes via ring opening of the epoxide by sodium azide and subsequent triphenylphosphine induced cyclization. BF3-induced reaction of compounds 3a-e resulted in a rearrangement via a cyclopropyl carbinyl cation intermediate. In the case of tosylaziridine 3c bicyclic product 5, (tropane skeleton), was formed as the major product. With carbamate derivative 3a exclusive rearrangement to fluorocyloheptene 7 took place.
34.	Nájera, Carmen, et al. (författare) Nitroselenation of conjugated dienes : Preparation of 3,4-epoxy-3-nitro-1-alkenes 1990 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 31:29, s. 4199-4202 Tidskriftsartikel (refereegranskat)abstract Conjugated dienes were transformed to synthetically useful 3,4-epoxy-3-nitro-1-alkenes via a nitroselenation-oxidation sequence. Conjugated dienes were transformed to synthetically useful 3,4-epoxy-3-nitroalkenes via a nitroselenation-oxidation sequence.
35.	Olofsson, Berit, et al. (författare) Determination of the relative configuration of vic-amino alcohols 2003 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 44:6, s. 1279-1281 Tidskriftsartikel (refereegranskat)abstract A large set of syn- and anti-1,2-amino alcohols has been synthesized. Upon comparison of the CHO and CHN H-1 NMR shifts a general trend has been observed, making it possible to determine the relative configuration of 1,2-amino alcohols without derivatization or shift reagents.
36.	Pamies, Oscar, et al. (författare) An efficient and mild ruthenium-catalyzed racemization of amines : application to the synthesis of enantiomerically pure amines. 2002 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 43:26, s. 4699-4702 Tidskriftsartikel (refereegranskat)abstract An efficient and mild Ru-catalyzed racemization of amines under transfer hydrogenation conditions is reported. A significant advantage of this new procedure is that the ruthenium hydrogen transfer catalysts allow high functional group tolerance. Interestingly, both primary and secondary amines were efficiently racemized under these conditions. We also report on the combination of this new amine racemization with an enzymic kinetic resoln. of primary amines. [on SciFinder(R)]
37.	Ray, C. A., et al. (författare) Lewis acid-catalyzed hetero Diels-Alder cycloadditions of 3-alkyl, 3-phenyl and 3-carboxylated 2H-azirines 2001 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 42:52, s. 9289-9291 Tidskriftsartikel (refereegranskat)abstract Activation by Lewis acids of 3-alkyl and 3-phenyl 2H-azirines promotes their participation in hetero Diels-Alder reactions with a variety of dienes. This methodology circumvents the previous requirement of an electron-withdrawing carboxyl moiety at the 3-position of the 2H-azirine.
38.	Rosenthal, Katri, et al. (författare) 4-(3-Hydroxy-4-methylpentyl)phenylacetic acid as a new linker for the solid phase synthesis of peptides with Boc chemistry 1999 Ingår i: Tetrahedron Letters. - 0040-4039 .- 1359-8562. ; 40:2, s. 377-380 Tidskriftsartikel (refereegranskat)abstract The anchoring the first amino acid in Boc chemistry to a 4-(3-hydroxy-4-methylpentyl)phenylacetic acid linker is described and compared to the conventional Pam resin. The peptidyl-4-(4-methyl-3-pentoxy)phenylacetamide linkage is slightly more stable to TFA than the Pam linker but in contrast to the Pam linker stable to cleavage of benzylic protective groups with TFMSA/DMS/TFA mixtures. This allows a mild and convenient two step deprotection procedure using the “low TFMSA-high HF”. In HF this new linker reacts preferentially in an intramolecular reaction forming a tetrahydronaphthalene derivative.
39.	Tholander, J, et al. (författare) Synthesis of 6-formylindolo[3,2-b]carbazole, an extremely potent ligand for the aryl hydrogen (Ah) receptor 1998 Ingår i: TETRAHEDRON LETTERS. - 0040-4039. ; 39:12, s. 1619-1622 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
40.	Timen, A. S., et al. (författare) Improved procedure for cyclization of vinyl azides into 3-substituted-2H-azirines 2003 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 44:28, s. 5339-5341 Tidskriftsartikel (refereegranskat)abstract A significantly improved procedure for the preparation of 3-substituted 2H-azirines has been developed. By cyclization of the corresponding vinyl azides in low boiling solvents in closed vessels at elevated temperature, high purity, short reaction time and simple isolation of the product were achieved.
41.	Unelius, C. Rikard, et al. (författare) Identification and synthesis of the sex pheromone of Phtheochroa cranaodes (Lepidoptera : Tortricidae) 1996 Ingår i: Tetrahedron Letters. - : Elsevier. - 0040-4039 .- 1359-8562. ; 37:9, s. 1505-1508 Tidskriftsartikel (refereegranskat)abstract The pheromone of Phtheochroa cranaodes (Lepidoptera: Tortricidae) was identified as (3E,SZ)-3,5-dodecadienyl acetate (5) by GC-MS analysis of female gland extracts and field trapping of males with synthetic compound.
42.	vanderLaan, AC, et al. (författare) An approach towards the synthesis of oligomers containing a N-2-hydroxyethyl-aminomethylphosphonate backbone: A novel PNA analogue 1996 Ingår i: TETRAHEDRON LETTERS. - : Elsevier BV. - 0040-4039. ; 37:43, s. 7857-7860 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
43.	Ahlford, Katrin, et al. (författare) Fine-tuning catalytic activity and selectivity-[Rh(amino acid thioamide)] complexes for efficient ketone reduction 2009 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 50:46, s. 6321-6324 Tidskriftsartikel (refereegranskat)abstract Amino acid-derived thioamides are prepared and evaluated as ligands in the rhodium-catalyzed asymmetric transfer hydrogenation of ketones in 2-propanol. It is found that increasing the steric bulk at the C-terminus of the ligand had a positive impact on both activity and selectivity in the reduction reaction. In order to find the optimum catalyst, a study is performed on a series of thioamide ligands having substituents of varying size.
44.	Ahmad, Anees, et al. (författare) Oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III) 2013 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 54:43, s. 5818-5820 Tidskriftsartikel (refereegranskat)abstract A novel protocol for the oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III) was developed. This approach uses inexpensive, readily available, and stable chemicals (PhI, mCPBA, and TsOH) giving rearrangement products in yields comparable to those obtained using the more expensive commercially available [hydroxy(tosyloxy)iodo]benzene [HTIB or Koser's reagent]. Additionally, an alternative protocol for the synthesis of 1-methyl-2-tetralone through the one-step epoxidation/rearrangement of 4-methyl-1,2-dihydronaphthalene using mCPBA and TsOH was developed.
45.	Akhtar, Tashfeen, et al. (författare) Investigations into the synthesis of amine-linked neodisaccharides 2007 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039. ; 48, s. 8673-8677 Tidskriftsartikel (refereegranskat)
46.	Almesåker, Ann, et al. (författare) One-pot synthesis of tripodal tris(2-aminoethyl)amine derivatives from seven molecular components 2009 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 50:16, s. 1847-1850 Tidskriftsartikel (refereegranskat)abstract Complex tripodal tris(2-aminoethyl)amine (tren)-based ligands have been prepared in a single-pot reaction of tren with 3 equiv each of cyclohexenone and a benzaldehyde derivative (i.e., from seven components and three molecular types). The highest yield of product was obtained for p-nitrobenzaldehyde, the most electrophilic aldehyde used. (C) 2009 Published by Elsevier Ltd.
47.	Ambala, S, et al. (författare) N-Arylation of primary and tertiary sulfonimidamides (SIAs) with benzyne precursors under transition metal-free conditions 2023 Ingår i: TETRAHEDRON LETTERS. - 0040-4039. ; 124 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
48.	Amedjkouh, Mohamed, 1966, et al. (författare) Self-reproduction of chirality on alpha-aminophosphonates: asymmetric synthesis of alpha-alkylated diethyl pyrrolidin-2-yl-phosphonate 2004 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039. ; 45:26, s. 5175-5177 Tidskriftsartikel (refereegranskat)abstract A simple method for the asymmetric synthesis of alpha-substituted diethyl pyrrolidin-2-yl-phosphonate is described. The chiral oxazolopyrrolidine phosphonate was alkylated diastereospecifically with an alkyl halide. The key intermediate is an alpha-phosphonate-stabilized carbanion that can be alkylated without loss of optical activity and a single enantiomer of product was formed exclusively in 10-80% yield. The configurational assignment of the products relied on H-1-H-1 NOESY analysis of the alkylated oxazolopyrrolidine phosphonates. This represents an unprecedented case of self-regeneration of stereocenters (SRS) of cyclic aminophosphonates. The enantiomerically pure alpha-aminophosphonate dietlhyl-(2S)-(2-methylpyrrolidin-2-yl)-phosphonate, a surrogate of 2-methyl proline, was obtained upon hydrogenolysis of the chiral auxiliary in 83% yield. (C) 2004 Elsevier Ltd. All rights reserved.
49.	Amirkhanov, NV, et al. (författare) The recognition and cleavage of RNA in the antisense oligo-RNA hybrid duplexes by RNase H 2001 Ingår i: TETRAHEDRON LETTERS. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0040-4039. ; 42:3, s. 489-491 Tidskriftsartikel (refereegranskat)abstract The different extent of the target RNA cleavage at t(99.9%) by RNase H in the AON-RNA duplexes, at the RNA saturation condition by antisense oligo, is due to different recognition and catalytic properties of RNase H toward the hybrids owing to different s
50.	Andaloussi, Mounir, et al. (författare) A convenient synthesis of linear pyridinoimidazo[1,2-a] pyridine and pyrroloimidazo[1,2-a] pyridine cores 2007 Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 48:47, s. 8392-8395 Tidskriftsartikel (refereegranskat)abstract Two new imidazo[1,2-a] pyridine derivatives, pyridinoimidazo[1,2-a] pyridine (10) and pyrroloimidazo[1,2-a] pyridine (16), were synthesised from 2-amino-4-methyl-5-nitropyridine (1) by linear cyclisation, making use of dimethylformamide dimethylacetal (DMFDMA) as an agent of vinylamine functionalisation. This report describes first the formation of pyridine and pyrroloimidazopyridine from (1), and then the formation of pyridine-fused and pyrrolo-fused pyridine by the Friedlander method and reductive cyclisation followed by treatment of the resulting adduct with chloroacetaldehyde.

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