M-R functionalization

Pellegatta, R Chierchia, S.L. Zocchi, M.R. Functional association of platelet endothelial cell adhesion molecule-1 and phosphoinositide 3-kinase in human neutrophils. J. Biol. Chem., 273, 27768-27771 (1998)... 

McCLintock, T.S. Graminski, G.R Ptenza, M.N. Jayawickreme, C.K. Roby-Shemkovitz, A. Lerner, M.R. Functional Expression of Recombinant G Protein Coupled Receptors Monitored by Video Imaging of Pigment Movement in Melanophores, Anal. Biochem. 209, 298-305 (1993). 

Scheme 1 General catalytic cycle for the CH activation/M-R functionalization of a hydrocarbon (RH)...

These considerations demonstrate that strongly acidic media are essential in electrophihc systems. The acid solvent plays an important role as a weakly coordinating media that is resistant to oxidation and facihtates in alkane coordination by anion protonation increasing metal lability. The acid also plays an important role in the M-R fimctionahzation step. In aU of these systems, M-R functionalization proceeds by reductive functionahzation where the metal center is reduced by two oxidation states from to M [Eq. (4)]. Consequently, as with the CH cleavage, it can be expected that this step would be facihtated by increased electrophilicity at the metal center as this favors reductive functionalizations. 

Scheme 5 General strategy for catalyst design based on coupling CH activation with M-R functionalization using an O-atom donor or electron-acceptor. Ox, that is regenerated by air in a...

Loken, M. R. Functional multi-drug resistance assay. U.S. Pat. Appl. Publ. US 20060263834,2006. 

The BV-type transition state involves concerted methyl migration and IO3 loss as observed by stretching of the C-Re bond from 2.168 A to 2.516 A and the I-O bond from 1.803 A to 2.399 A. Similar to BV or alkyl borane oxidation reactions in organic chemistry, this transition state can be described as a formal insertion of an electrophilic O into the Re-CH3 bond. While it is possible that a more exhaustive investigation could lead to alternative low-energy pathways, these results emphasize that a BV-type pathway can be considered as a particularly facile route for M-R functionalizations. 

These results are encouraging and may point to a facile pathway for heteroatom functionalization of M-R intermediates of more electron-rich metals via a BV-type pathway with electrophihc, O-atom donors, YO. Howevei there are some key considerations that must be addressed before we can determine if this pathway will be broadly appHcable for M-R functionalizations. In MTO, rheni-... 

Fletcher R and Reeves C M 1964 Function minimization by conjugate gradients Comput. J. 7 149... 

Noble M E M, R K Wierenga, A-M Lambeir, F R Opperdoes, W H Thunnissen, K H Kalk, H Groendijk and W G J Hoi 1991. The Adaptability of the Active Site of Trypanosomal Triosephosphate Isomerase as Observed in the Crystal Structures of Three Different Complexes. Proteins Structure, Function and Genetics 10 50-69. 

Fig. 10. Comparison of the measured refractive indices for PET film with values calculated from the orientation functions determined from n.m.r. assuming transversely isotropic structural units. I, Experimental points predicted values. Reproduced from Polymer by permission of the publishers, Butterworth Co (Publishers) Ltd. (C)...

The fundamental equation of sedimentation equihbrium can be manipulated to define a new function with dimensions of molar mass (g/mol) called M r). M (r) at a radial position r is defined by... 

E. Castillo and M. R. Ruiz-Cobo, Functional Equations and Modelling in Science and Engineering (1992)... 

Before going into detail on the different M R configurations, it should be realized that the main function of the membrane can be different for each configuration ... 

Imamura M, Seyedi N, Lander HM, Levi R Functional identification of histamine H3-receptors in the human heart. Circ Res 1995 77 206. 

The non-equivalence of the ester protons in the monomethyl- and monophenyl-phosphinic ester function, as in (44, Ch = chalkogen), has been studied. Compounds of type (45) have some interesting stereochemistry. They are prepared from racemic secondary butyl alcohol, and the presence of three signals in the P n.m.r. spectrum confirms that the phosphorus atom is the centre of pseudo-asymmetry. A 1 2 1 triplet is observed which is attributed to the presence of equal amounts of two mesa forms, (45) and (46), which have different values of Sp (outer peaks), and two racemic forms, (47) and (48), which have identical values of 8p (central peak). 

Busch, M., Seuter, A., and Hain, R., Functional analysis of the early steps of carotenoid biosynthesis in tobacco. Plant Physiol. 128, 439, 2002. 

Zingeser M.R. (1984). The nasopalatine ducts and associated structures in the rb monkey (Macaca mulatto) — topography, prenatal development, function phylogeny. Am J Anat 170, 581-595. 

Blomberg, M. R. A., Siegbahn, P. E. M., Svensson, M., 1996, Comparisons of Results From Parameterized Configuration Interaction (PCI-80) and From Hybrid Density Functional Theory With Experiments for First Row Transition Metal Compounds , J. Chem. Phys., 104, 9546. 

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