Question

Two form of D-glucopyranose are called:: (1)enantiomers(2) anisomers(3)diastereoisomers

Answer 1

The cyclic form of glucose is called glucopyranose. Nucleophillic attack on a planar carbonyl group can occur from either face, leading to two different stereochemical outcomes to two different diastereomers. In carbohydrate nomenclature, these two diastereomers are referred to as the alpha and beta anomers of glucopyranose.
So it is called anomers of glucopyranose.