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101.
102.
Joann Huber Robert G.K. Donald Sang Ho Lee Lisa Wang Jarantow Michael J. Salvatore Xin Meng Ronald Painter Russell H. Onishi James Occi Karen Dorso Katherine Young Young Whan Park Stephen Skwish Michael J. Szymonifka Tim S. Waddell Lynn Miesel John W. Phillips Terry Roemer 《Chemistry & biology》2009,16(8):837-848
103.
Salvatore Pincherle 《Annali di Matematica Pura ed Applicata》1936,15(1):243-308
Alcuni dei risultati qui contenuti trovansi riassunti nella Nota postuma:S. Pincherle,Sulla permutabilità negli operatori lineari, ? Bollettino dell'Un. Mat. It. ?, t. 15 (1936), pp. 153–161; va inoltre avvertito che — colla scomparsa del compianto Maestro
— l'ultimo capitolo della presente Memoria è rimasto incompleto, ciò che però non nuoce all'organicità del lavoro. 相似文献
104.
105.
Enzo Cadoni Massimiliano Arca Claudia Fattuoni Maria G. Cabiddu Salvatore Cabiddu 《Tetrahedron》2008,64(27):6349-6357
The sulfinyl carbanion derived from 2,3-dihydro-1-benzothiophene-1-oxide and its lithium salt has been investigated by DFT calculations. The lithium carbanion was treated with aldehydes and imines to give chiral hydroxy and amino derivatives, with high stereoselectivity at the carbon α to the sulfoxide group (trans diastereoisomers), but with low diastereoselectivity at the hydroxyl or amine group. DFT calculations were used to rationalize the different stereochemical behavior of cyclic and acyclic lithiated sulfoxides in the reaction with aldehydes and azomethines. 相似文献
106.
Serena Fiorito Francesco Epifano Francesca Preziuso Vito Alessandro Taddeo Claudio Santi Salvatore Genovese 《Tetrahedron letters》2017,58(4):371-374
The chromane core is widely represented in nature being part of a wide array of secondary metabolites of plant, fungal, and bacterial origin. In this paper an improved method for the chemical synthesis of differently substituted chromanes is described. Substituted 2H-1-benzopyrans have been synthesized in good to excellent yields (52–81%) by treatment of 3,3-dimethylallyl and propenylbenzene ethers of differently substituted phenols with phenylselenyl chloride. 相似文献
107.
Animesh Roy Maximilian A. Silvestri Robert A. Hall Salvatore D. Lepore 《Tetrahedron letters》2017,58(1):106-108
In the attempt to synthesize substituted allenyl esters through a metathesis coupling of unsubstituted allenyl esters and alkenes using a variety of ruthenium catalysts, it was discovered that allenyl esters themselves cleanly arrested the activity of the catalysts. Further studies suggests possible utility of allene esters as general quenching agents for metathesis reactions. To explore this idea, several representative olefin metathesis reactions, including ring closing, were successfully terminated by the addition of simple allenyl esters for more convenient purification. 相似文献
108.
The direct synthesis of chlorolactones from differently substituted alkenoic acids, using either sodium hypochlorite or chloramine T as the source of electrophilic chlorine and ytterbium triflate hydrate as the Lewis acid is described. In both cases the reactions proceeded in good yields affording selectively five- or six-membered chlorolactones. 相似文献
109.
Cali F Ragalmuto A Chiavetta V Calabrese G Fichera M Vinci M Ruggeri G Schinocca P Sturnio M Romano S Romano V Elia M 《Experimental & molecular medicine》2010,42(12):842-848
Angelman syndrome (AS) is a severe neurobehavioural disorder caused by failure of expression of the maternal copy of the imprinted domain located on 15q11-q13. There are different mechanisms leading to AS: maternal microdeletion, uniparental disomy, defects in a putative imprinting centre, mutations of the E3 ubiquitin protein ligase (UBE3A) gene. However, some of suspected cases of AS are still scored negative to all the latter mutations. Recently, it has been shown that a proportion of negative cases bear large deletions overlapping one or more exons of the UBE3A gene. These deletions are difficult to detect by conventional gene-scanning methods due to the masking effect by the non-deleted allele. In this study, we have used for the first time multiplex ligation-dependent probe amplification (MLPA) and comparative multiplex dosage analysis (CMDA) to search for large deletions affecting the UBE3A gene. Using this approach, we identified a novel causative deletion involving exon 8 in an affected sibling. Based on our results, we propose the use of MLPA as a fast, accurate and inexpensive test to detect large deletions in the UBE3A gene in a small but significant percentage of AS patients. 相似文献
110.
Capillary electrochromatography (CEC) was coupled with mass spectrometry (MS) for the separation of some selected pesticides and drug enantiomers. CEC separations were carried out in fused silica capillaries packed with either 5 μm RP18 silica or 5 μm silica modified vancomycin particles. The capillary column was connected with the MS utilizing a laboratory-made liquid-junction interface equipped with a 50 μm I.D. capillary-tip positioned at a few mm from the orifice of the MS. The CEC–MS set-up was operated without external pressure assistance during the electrochromatographic run commonly used to avoid bubble formation. However a hydrostatic pressure of a few kPa was applied only to the liquid-junction interface to optimize the ion-spray due to the low I.D. of the capillary-tip. In order to optimize the CEC–MS method, several experimental parameters were studied, namely the inlet pressure, the hydrostatic pressure into the liquid-junction interface, the type of sheath-liquid and the mobile phase. The application of an inlet pressure influenced only analyte retention times that were shortened by increasing the pressure. On the contrary the hydrostatic pressure applied to the interface increased the flow rate into the tip also increasing the ion-signal recorded in the mass spectrometry. The ion-signal raised almost linearly by increasing the outlet pressure till 3.5 kPa and then decreased. The separation of the selected pesticides was not influenced at all changing the hydrostatic pressure on the interface. Some basic enantiomeric compounds of pharmaceutical interest were successfully separated by CEC achieving good resolution. They were detected by MS with limit of detection in a range of 0.24–0.60 μg/mL. 相似文献