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141.
Ishihama Y Katayama H Asakawa N Oda Y 《Rapid communications in mass spectrometry : RCM》2002,16(10):913-918
Tapered stainless steel spray tips for sheathless microelectrospray ionization (microESI) have been developed. The fabrication procedure for the tapered stainless steel tips was optimized using an electropolishing technique followed by removal of the burr. Using the tip as the microESI emitter, a stable ESI spray was obtained at a flow rate of 20 nL/min. The sensitivity of the microESI system was almost two orders greater than that of the conventional ion spray system. The tip was highly stable, and was successfully used for over 1000 h. Moreover, these stainless steel tips were suitable for use with sheathless capillary electrophoresis/mass spectrometry (CE/MS) and capillary liquid chromatography/mass spectrometry (LC/MS) for routine analysis in proteomic and pharmaceutical applications. 相似文献
142.
Reaction of bicyclo[4.2.0]octane-2,5-diones with trimethylsilyl iodide gave bicyclo[3.3.0]oct-1(5)-en-2-ones by a clean reductive rearrangement in good yields, providing a simple and effecient synthetic method for the enones. 相似文献
143.
T Nakagawa Y Oda A Shibukawa H Fukuda H Tanaka 《Chemical & pharmaceutical bulletin》1989,37(3):707-711
Electrokinetic chromatography using a fused silica capillary and sodium dodecyl sulfate (SDS) solution has been applied to the separation and determination of cefpiramide (CPM) in human plasma with the use of antipyrine (AP) as an internal standard. A plasma sample was introduced into the capillary by siphoning. The calibration plot for CPM in plasma sample showed good linearity in the concentration range over 10 to 300 micrograms/ml. This method has advantages over usual high performance liquid chromatography (HPLC) in that it needs only a very small volume (less than 10 nl) of plasma without pretreatment, and an extremely high separation efficiency (10 times or much higher plate number than usual HPLC) is obtained. The addition of SDS to the supporting electrolyte solution enabled (1) rapid release of protein-bound drug which allowed the total concentration to be determined, (2) reproducible results to be obtained by suppressing adsorption of protein onto the fused silica capillary and (3) rapid separation of drug from proteins by selective retardation of protein peaks. 相似文献
144.
145.
Rui Tamura Koji Hayashi Masato Kakihana Masanori Tsuji Daihei Oda 《Tetrahedron letters》1985,26(7):851-854
Allylic nitro compounds undergo denitro-sulfonylation catalyzed by Pd(PPh3)4 or Pd(PPh3)4 +NaNO2 with PhSO2Na·2H2O to afford allylic sulfones regioselectively. 相似文献
146.
147.
148.
Nguyen Chung Thanh Takanori Kajioka Yasunori Taga Satoshi Ogawa Yosuke Miyahara Mitsunori Oda 《Tetrahedron》2006,62(48):11227-11239
After a preliminary search of the reaction conditions for the Suzuki-Miyaura cross-coupling of haloazulenes with arylboronic acids, the title compounds were synthesized either by the direct coupling reaction between 1,3-dihaloazulene and the corresponding N,N-disubstituted 4-aminophenylboronic acids or by a two-step sequence involving the cross-coupling with 4-bromophenylboronic acid and subsequent Pd-catalyzed amination. Application of the title diamines to a hole-injecting material in organic electroluminescent devices was carried out to provide their prominent characteristics as a novel durable, non-cyanine and non-polyamine substance without color fade. The diamine derivatives, extended by an ethynyl unit between the azulenyl core and the 4-aminophenyl moiety, were also synthesized and found, unfortunately, unsuitable for vacuum deposition in preparing a multilayer composite. 相似文献
149.