The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Modifications of a macrolide antibiotic midecamycin (SF-837). I. Synthesis and structure of 9,3''-diacetylmidecamycin.

9,3''-Diacetylmidecamycin (12) was synthesized from 4''-depropionyl-9,2',4''-triacetylmidecamycin (8) by heating the latter with propionic anhydride in pyridine followed by removal of 2'-acetyl group, with or without 18-enolpropionyl group. Direct acetylation of midecamycin (1) led to the formation of the 3'',4''-positional isomer (6). The structure of 12 was determined by mass, NMR and chemical degradation. The location of 3''-acetyl group was shown by the stereospecific 3 leads to 1 acetyl migration catalyzed by a base of 3-O-acetyl-4-O-propionyl-L-mycarose (13), and comparison of NMR and mass fragmentation with the 3,4-positional isomer (15). The latter's structure was independently supported by the nuclear Overhauser effect between methyl and propionyl group at C-3. The intramolecular 4 leads to 3 acyl shift that was taken place in the forced acylation of the mycarose moiety was found to be affected by the anomeric configuration, nature of aglycones and reaction temperature. Reverse 3 leads to 4 acyl migration occurred in acidic hydrolysis.[1]

References

 
WikiGenes - Universities