M s fragments

Table 2. Iminoboranes for which details of m.s. fragmentation have been published...

F. Protonation, Alkylation, and Redox Chemistry of Complexes with [M(S )] Fragments / 623... 

In summary, the electronic flexibility of [M(S )] fragments gives rise to very diverse complexes, structures, and reactivities. 

Thiolate donors in [M(S )] fragments with coordinatively unsaturated metal centers may stabilize these metal centers by either n donation or formation of M—S—M bridges. 

The nucleophilic addition of organolithium compounds to CO ligands is a characteristic reaction of metal carbonyl complexes. This reaction can also be observed when CO binds to [M(S )] fragments. The reaction according to Eq. 36 has been selected because the resulting benzoylato complex was characterized by X-ray crystallography (118). 

Mass spectral, o.r.d., and c.d. studies have been carried out on unnatural b/c /rans-fused morphine derivatives. Characteristic dilferences between m.s. fragmentation patterns of C-14 epimeric derivatives were observed which should have diagnostic value. Mass spectral investigations were also used in structural and stereochemical assignments of benzomorphan derivatives. The C n.m.r. spectrum of codeine has been analysed. A method for selective... 

Nir, E., Hunziker, H.E., and de Vries, M.S., "Fragment Free Mass Spectrometric Analysis with Jet Cooling/VUV Photoionization," Anal. Chem. 71, 1674—1678, 1999. 

The electron inqtact m.s. fragmentation pattern of l-[(2 -carbonyl)-pyrrolidinyl]-l-deoxy-D-fructose shows two main fragmentation pathways initiated by ring O and amino N, giving stabilized oxonium and imminium ions. ... 

Neuraminic acids have been reduced with sodium borohydride and the m.s. fragmentation patterns of the corresponding peracetylated methyl esters of 5-acylamino-3,5-dideoxy-nononic and -heptonic acids have been recorded. A set of partially O-methylated derivatives of methyl A-acetyl-A-methyl-jS-o-neuraminate methyl glycoside have been prepared as reference compounds... 

For a basic diagram consisting of m, s—fragments followed by a part lying entirely above the 0 line, (VIII-2) stiU holds for j 2, but Wq and Wj are given by... 

The retention times of the pertrimethylsilyl ether derivatives of seventeen disaccharides were determined for two liquid phases, and an attempt was made to relate these to structural features. A quantitative analysis of 2-deoxy-scy//o-inosose by g.c.-m.s. with selected ion monitoring was used to study its enzymatic synthesis, and its m.s. fragmentation was studied using the [2,2- HJ-labelled derivative. ... 

The e.i.-m.s. fragmentation patterns of some benzoylated 5-[poly(benzoyloxy)alkyl]tetrazoles have been reported. 

H-(3-Ethylindolyl)-D-xylopyranosylamine, eight H-(substituted-phenyl)pentopyranosylamines, and their M-nitroso-derivatives have been synthesized and their mutagenicities reported. The synthesis and antitumour activity of quaternary ellipticine N-glycosides is covered in Chapter 19, and the e.i.-m.s. fragmentation of per-Q-acetylated H-(4-substituted-phenyl)glycopyranosylamines in Chapter 22. 

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