CHO H OH HH OHH CH,OH HO H HOCH2 CHO OH CHO H OH OH OHH OH OH OH CH,OH HoH CH,OH CH,OH OH O、OH OH CHO OH OH OH OH OH 2 OH OH 不需指明α、β时 D B-D CHOH Haworth式二者互为异构体 OH HOH OH OHα-D β-D Haworth 式二者互为异构体 HOH OH OH OH CH2OH O 不需指明α 、β时 CH2OH H OH H OH HO H H OH CHO CHO OH OH H H H OHOH H HOCH2 CHO OH OH OH OH CH2OH 1 3 2 4 5 6 CHO OH OH OH CH2OH OH 1 3 2 4 5 6 OH OH OH OH CH2OH O + OH OH OH OH CH2OH O