Question

Which of the following structures has the a configuration? HOCH2 HOCH2 HOCH2 HOCH, H —0 ОН НО — -ООН н -он Но он КӨн Но кон н Конн HO Ун Н H HO ОН Н н н н он н он н он тартата B Answers A-D A none of them в A&B Previous UESTIONS VERSION 3.8.1 WE R T rul F G H J s o K сув N

Answer 1

alfa or betaconfiguration is told by the group on carbon adjacent to O (ether grouop) known as anomeric carbon. Thus configuration is determined by position of substituent on anomeric carbon.

If OH group is right side or below side, then it is alfa configuration.

If OH group is on left or above side, then it is beta configuration.

In C and D, OH is below on anomeric carbon, hence (C) and (D) have alfa configuration.

in A and B, OH is above on anomeric carbon, hence beta configuration.