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101.
A simple and efficient one-pot method has been developed for the synthesis of α-aminonitriles from aldehydes, amines, and trimethylsilyl cyanide in the presence of a catalytic amount of bismuth trichloride. 相似文献
102.
Gibbs JM Park SJ Anderson DR Watson KJ Mirkin CA Nguyen ST 《Journal of the American Chemical Society》2005,127(4):1170-1178
The syntheses of several norbornene block copolymers containing oligonucleotide and ferrocenyl side chains and their use in the electrochemical detection of DNA are described. Two kinds of DNA-containing block copolymers with either ferrocenyl or dibromoferrocenyl groups were prepared via ring-opening metathesis polymerization (ROMP). Based on these two distinct ferrocene derivatives, a triblock copolymer labeling strategy was developed. With this strategy, the identity of DNA target can be determined by the E1/2s of the ferrocenyl moieties and the ratio of peak currents. These polymers exhibit predictable and tailorable electrochemical properties, high DNA duplex stability, and unusually sharp melting transitions, which are highly desirable characteristics for DNA detection applications. Significantly, single-base mismatches could be easily detected using two distinct block copolymers as dual-channel detection probes in an electrochemical DNA detection format. 相似文献
103.
Andrew T. Placzek James L. Donelson Rushi Trivedi Richard A. Gibbs Surya K. De 《Tetrahedron letters》2005,46(52):9029-9034
A simple and efficient method has been developed for the synthesis of β-amino alcohols by ring opening of epoxides in the presence of a catalytic amount of Sc(OTf)3 at room temperature under solvent-free conditions. The reaction works well with both aromatic and aliphatic amines. High regio-, and diastereoselectivity can be considered as a noteworthy advantage of this method. 相似文献
104.
Henriksen BS Zahn TJ Evanseck JD Firestine SM Gibbs RA 《Journal of chemical information and modeling》2005,45(4):1047-1052
Protein farnesyltransferase (FTase) is an important anticancer drug target. In an effort to develop isoprenoid diphosphate-based FTase inhibitors, striking variations have been observed in the ability of conservatively modified analogues to bind to the enzyme. For example, 2Z-GGPP is an alternative substrate with high binding affinity, while GGPP is not an alternative substrate. Using the availability of high-resolution FTase crystal structures, we have used pharmacophore and docking studies to elucidate a new binding pocket for isoprenoid analogues. The unique conformations between the first two isoprene units of 2Z-GGPP, but not GGPP, allows 2Z-GGPP to exploit this new binding pocket. The discovered conformation allows the molecule to adopt a reactive conformation while placing hydrophobic groups within the predominately hydrophobic binding pocket. This computational finding is supported by NMR studies on (13)C-labeled 2Z-farnesol, which confirm that the computationally predicted conformation is also favored in solution. These discoveries suggest that ligand conformational flexibility may be an important design consideration for the development of both inhibitors and alternative substrates of FTase. 相似文献
105.
106.
107.
Wolcott Gibbs 《Fresenius' Journal of Analytical Chemistry》1884,23(1):543-544
Ohne Zusammenfassung 相似文献
108.
Wolcott Gibbs 《Fresenius' Journal of Analytical Chemistry》1873,12(1):306-307
Ohne Zusammenfassung 相似文献
109.
Gibbs SL Chen B O'Hara JA Hoopes PJ Hasan T Pogue BW 《Photochemistry and photobiology》2006,82(5):1334-1341
Protoporphyrin IX (PpIX) is produced in cells via the heme synthesis pathway, from the substrate aminolevulinic acid (ALA), and can be used for tumor detection, monitoring or photodynamic therapy. PpIX production varies considerably between tumor cell types, and determining the cell types and methods to optimize production is a central issue in properly utilizing this drug. A panel of eight cancer cell types was examined for PpIX production capacity, including breast, prostate, and brain cancer tumors, and the production varied up to 10-fold among cell types. A positive correlation was seen between mitochondrial content and naturally occurring PpIX prior to ALA administration, but mitochondrial content did not correlate to the yield of PpIX resulting from the addition of ALA. Interestingly, total cell size was positively correlated to the yield of PpIX from ALA administration. Addition of an iron chelator, 1,2-dimethyl-3-hydroxy-4-pyridone (L1) in combination with ALA allows the final step in the heme synthesis pathway, conversion of PpIX to heme, to be delayed, thereby further increasing the yield of PpIX. Those cell types that had the lowest ALA to PpIX production without L1 showed the largest percentage increase in production with L1. The study indicates that use of L1 in tumors with a lower innate production of PpIX with ALA alone may be the most productive approach to this combined delivery. 相似文献
110.
Wolcott Gibbs 《Fresenius' Journal of Analytical Chemistry》1868,7(1):94-96
Ohne Zusammenfassung 相似文献