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)
 
 
 

Synthesis and stereochemistry of 7 beta- and 7 alpha-amino-, acetamido-, hemisuccinamido- and terephthalamido derivatives of testosterone.

The reduction of 3-ethylenedioxy-7-oximino-5-androsten-17 beta-yl acetate and of its 17 beta-tetrahydropyranyl ether analog with sodium in ethanol, followed by thin-layer chromatography, allowed the isolation of the corresponding 17 beta-hydroxy- and 17 beta-tetrahydropyranyloxy-5-en-7 beta- and 7 alpha-amines which were also characterized as 7-acetamides. The acylation of the two epimeric 17 beta-hydroxy-5-en-7-amines with succinic anhydride followed by selective saponification of the 17 beta-hemisuccinate group and diazomethane esterification, gave the corresponding 17 beta-hydroxy-5-en-7 beta- and 7 alpha-hemisuccinamido methyl esters characterized also as 17 beta-acetates. On the other hand, the acylation of the two 17 beta-tetrahydropyranyloxy-5-en-7-amines with the acid chloride of terephthalic acid monomethyl ester led to the more rigid 7 beta- and 7 alpha-terephthalamido methyl ester side-chains. The acidolysis of the 3-ethyleneketal protecting group of the preceding 5-en-7-N-acyl derivatives regenerated the 4-en-3-oxo function while the 17 beta-tetrahydropyranyl ether group was cleaved simultaneously into the 17 beta-alcohol. The four desired 7 beta- and 7 alpha-hemisuccinamido- and terephthalamido carboxylic side-chain derivatives of 17 beta-hydroxy-4-androsten-3-one (testosterone) were finally obtained by saponification of the corresponding methyl esters.[1]

References

 
WikiGenes - Universities