Trisaccharide Linkages

[pnoybballin]

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Hey everyone so on this picture http://www.uky.edu/~dhild/biochem/10/oligosaccharides1.gif the left compound is Raffinose and I was wondering if someone could please explain why the linkage between alpha-D-galactose and alpha-D-glucose is named alpha-1,4? More specifically, I don't understand where the 4 is coming from. Isn't it linked to the 6th carbon making it really alpha-1,6? Thanks a lot everyone.

 

[loveoforganic]

Hm, that looks like the 5th carbon to me. The last sugar is a ketohexose, isn't it?