Cabonyl group

The enzyime is a single enantioimer of a chual imolecule and binds the coenzyime and substrate in such a way that hydride is transfened exclusively to the face of the cabonyl group that leads to (5)-(-l-)-lactic acid. Reduction of pyruvic acid in the absence of an enzyime however, say with sodium borohydride, also gives lactic acid but as a racemic mixture containing equal quantities of the R and S enantiomers. 

Scheme 3.6 Introduction of metbyl groups into ring E of alnusenone via a cabonyl group as auxiliary function...

The spectrum of the leucine-enkephalin methyl ester shows a series of diagnostic 14 dalton shifts for the C-terminus-containing fragment ions. In addition, the molecular ion has shifted positively by 14 daltons, consistent with the single reactive cabonyl group in the molecule. In contrast to the previously shown N-acetylation results, methyl esterification produces shifts in the complementary set of ions as shown below. By using N-acetyl and methyl ester derivatives one can obtain sequence information from both the N- and C-terminus of a peptide, while at the same time improving FAB mass spectral performance. 

Our group in 2014 developed the first cabonylative [3-I-2-I-1] annulation of Af-pyridyl anilines with internal alkynes and Mo(CO)g toward the facile synthesis of 2-quinolinones, and 19 examples were synthesized [40]. Here, the solid CO source Mo(CO)g was used instead of the CO gas which was highly toxic (Table 15.30). A series of symmetric and asymmetric internal alkynes could... 

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