Alpha/Beta sugars

[Sammy1024]

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So I was wondering how you could count the carbons on a sugar ring? I always count from the O CW but a questions I did counted them both directions.

Also does cis/trans connection affect the type of bonding (Alpha vs. Beta)?

I thought these were two alpha connections but it was alpha beta

Also I don't see how this is an acetal bond.

I can see the O and the second sugar as being the OR, but where is the other OR?

 

[deleted439911]

For alpha and beta. I remember this acronym AtBc. This means alpha anomer oxygen is trans to CH2OH and beta is cis to it.
For counting hexoses, I think it is simpler to remember that C-5 doesn't have a -OH group but is only attached to the CH2OH group, this is true for both furanoses and pyranoses

The other R is the first sugar. Sugar - O - Sugar = R-O-R