众透视式一 Fischer投影式 OH OH COOH H-C-COOH 中 H COOH◆ HO -H CH3 CH3 CH3 S S HO、 CH3 CH3 CH; ✉H HO- H HO H CH OH HO H OH CH3 H CH3HO H CH3 H CH3 OH CH3 HO H HO H CH3 透视式 Fischer投影式 C C HO H H CH3 OH CH3 H C COOH OH CH3 H OH COOH CH3 HO COOH H CH3 S S