The glycosidic bond angle is found in either the syn (0-90) or anti (180-270) conformation relative to the ribose.

Important coupling constants are:

Pyrimidines: J_H1'-C2 is found to be 2 Hz smaller than the J_H1'-C6 for the anti configuration, while the opposite is true for the syn case.

Purines: J_H1'-C4 is found to be 2 Hz smaller than the J_H1'-C8 for the anti configuration, while the opposite is true for the syn case.

Measurement of long-range H1'-C6/8 and H1'-C2/4 in 13C-labeled nucleic acids ( 02JB1-23 )