Are Anomers Epimers?

Question

epimers are the class of stereoisomers which differ along configuration at any carbon in a carbohydrate(generally),

And anomers are the kind of stereo isomers that differ at the carbonylic carbon, which becomes achiral only after hemiacetal (hemiketal) formation

Websites on search give that Epimers are bigger group where Anomers are a part of them, but in certain books on biochemistry like that of Lippincott(d.ferrier) writers define Epimers as change in configuration at any carbon except anomeric carbon..

So are Anomers Epimers?

Answer 1

IUPAC basic terminology of stereochemistry defines anomers and epimers:

Anomers

Diastereomers of glycosides, hemiacetals or related cyclic forms of sugars, or related molecules differing in configuration only at C-1 of an aldose, C-2 of a 2-ketose, etc.

Epimers

Diastereomers that have opposite configuration at only one of the two or more stereogenic centers present in the respective molecular entities.

So yes, anomers are a subset of epimers.

(Interestingly, on the contrary, ‘anomer’ term is exceptionally used in much broader meaning than ‘epimer’, in the term ‘anomeric effect’, which became generalized to e.g. conformations of molecules completely unrelated to saccharides.)