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Albert Defoin Hans Fritz Christian Schmidlin Jacques Streith 《Helvetica chimica acta》1987,70(3):554-569
N-Acylnitroso derivatives 6 which were prepared by in-situ oxidation of the corresponding hydroxamic acids 5 reacted instantaneously and in high yields with dihydropyridine 4 . The Diels-Alder adducts 8 were formed regiospecifically with the acylnitroso dienophiles 6a–c , whereas the dienophiles 6d–f gave mixtures of both regioisomers 7 and 8 . These and some other results [2] were best explained by the FMO theory. The Diels-Alder adducts 7 and 8 gave the corresponding ‘anti’-cis-glycols when reacted with OsO4/N-methylmorpholine N-oxide. Hydrogenolysis of the N–O bond followed by peracetylation led to the expected aminolyxose derivatives 14 and 16 . A similar sequence, using 4 and the hydroxamic-acid derivative 18 of (+)-D-mandelic acid led, with a poor asymmetric induction, to a mixture of the expected optically active aminolyxose compounds 19A / 19B . 相似文献
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The octahydroisoindolone moiety related to proxiphomin (1) has been synthesized by condensation of N-benzyloxycarbonyl-protected D, L-phenylalaninal (7) with methyl-(4-methyl-sorbyl)-malonate (11) to yield the branched ethylene derivative 12 . Consecutive intramolecular [2+4]-cycloaddition and lactam ring closure of 12 gave the desired octahydroisoindolone derivative 15 , possessing adaptable functional groups for the attachment of the macrocyclic ring system. 相似文献
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A. Rogai A. Monnier A. Blankart E. H. Riesenfeld B. Reinhold J. Schmidlin und P. Massini 《Fresenius' Journal of Analytical Chemistry》1925,67(7-8):307-312
Ohne Zusammenfassung 相似文献
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Tibur Schmidlin Remo Gamboni Peter Strazewski Christoph Tamm 《Helvetica chimica acta》1983,66(6):1796-1805
The stereo- and regiochemical course in the [2+4]cycloaddition of the chiral alkylidene malonic ester 1 to selected derivatives of (2E, 4E)-4-methyl-2, 4-hexadien-l-ol ( 2 ) and (2E, 4E)-4-methyl-2, 4-hexadien-l-al ( 12 ) has been investigated. The results are discussed on the basis of semiquantitative PMO theory. 相似文献
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Photolysis of Heterocyclic Azidinium Salts The photochemistry of some azidinium salts was investigated. Their photolusis led to a large variety of products which were isolated and identified. Reaction mechanisms involving singlet and triplet nitrene intermediates are discussed to explain the product formation. 相似文献
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Eric?Schmidlin Thierry?Wannier Jocelyne?Bloch Abderraouf?Belhaj-Saif Alexander?F?Wyss Eric?M?RouillerEmail author 《BMC neuroscience》2005,6(1):56
Background
After sub-total hemi-section of cervical cord at level C7/C8 in monkeys, the ipsilesional hand exhibited a paralysis for a couple of weeks, followed by incomplete recovery of manual dexterity, reaching a plateau after 40–50 days. Recently, we demonstrated that the level of the plateau was related to the size of the lesion and that progressive plastic changes of the motor map in the contralesional motor cortex, particularly the hand representation, took place following a comparable time course. The goal of the present study was to assess, in three macaque monkeys, whether the hand representation in the ipsilesional primary motor cortex (M1) was also affected by the cervical hemi-section. 相似文献9.
Fred W. Schmidlin 《Solid State Communications》1977,22(7):451-453
An analytic solution of the conventional multiple trapping problem is presented for the complete time domain and an arbitrary distribution of traps. The solution reduces to previously published solutions in appropriate limits. New methods are proposed for determining the microscopic mobility and trap densities. 相似文献
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Schmidlin DJ 《The Journal of the Acoustical Society of America》2007,121(6):3569-3578
For several decades there has been a great deal of interest in acoustic sensors that can make multiple measurements at a single point in the ocean. The order of such sensors has been defined by linking it to the order of the Taylor series approximation of the pressure field at that point. Following this definition, the pressure, vector, and dyadic sensor is of order zero, one, and two, respectively. For this theoretical study, a multichannel three-dimensional spatial filter is derived for a directional acoustic sensor of arbitrary order. Explicit formulas are found for the filter coefficients that maximize the array gain (directivity index) of the filter as well as an explicit expression for the maximum array gain (directivity index). This process is repeated for the case of a first-order null placed in the direction opposite to the look direction of the multichannel filter. Finally, an example is presented which tracks the array gain and beamwidth of a third-order acoustic sensor as the order of the null is assigned values 0, 1, 2, and 3. 相似文献