How to show stereochemistry of chair conformational functional groups?

[TotallyUncertain]

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Anomeric centre (alpha and beta) - CAZypedia

Scroll down to the bottom of the page I tried to emulate the B-D-glucofuranose functional group, but I am unsure.

 

[DAT Destroyer]

Hello,

I am given B-d- heptopyranose and one of the functional groups has an carbon that has stereochemistry. How do I go about drawing stereochemistry of the functional groups in both chair conformation and in haworth?

The functional group is attached to carbon 5 in the haworth. It is written as C4-(C5) - (C6)HOH-(C7)H2OH . As you can see the middle carbon has stereochemistry and if you write out the fischer projection, C6 has the OH on the right, which makes it R I think...

C5 is attached to my Oxygen.

I have not written out the other carbons. For reference, my molecule looks like this. sort of...

Anomeric centre (alpha and beta) - CAZypedia

Scroll down to the bottom of the page I tried to emulate the B-D-glucofuranose functional group, but I am unsure.

A 7 carbon sugar is very rare, but the methodology would be relatively straightforward. Take the O from Carbon 5 and attack the carbonyl group at C1. This will form the pyranose ring. At the anomeric carbon......place the OH up if beta, down if alpha. OK,,,,,for C2, C3, C4,,,,use the rule of DR LU.......Down with the OH if on Right......Left....put OH up. Now.....C5 has its O used to form the six membered pyranose ring.........this leaves C6 and C7........place these two carbons up...above the plane if a D sugar is desired. Mostly all sugars in nature are D,,,thus place it above the ring. Once the Haworth is drawn.....the chair is simply drawn by noting which groups are above and which groups are below a Hydrogen. This might sound a bit confusing, but this surely is NOT a DAT question. At any rate, I hope this helps. If not......consult any Organic text......Klein is the clearest on this......and this will lead the way for you.

Hope this helps

Dr. Jim Romano