Assign Priorities 0、20H C 3C..H4 NH2 natural alanine H CH expands to 4 H *C.CH(CH3)2 CH2OH *CCH(CH3)2 2 CH2OH 三> Chapter 5 10Chapter 5 10 Assign Priorities C C O OH H3C NH2 H natural alanine 1 2 3 4 Cl Cl H H * 1 2 3 4 1 2 3 4 => C C O H C H CH2 CH2OH CH(CH3) 2 * expands to C C O C CH2 CH2OH CH(CH3) 2 H O H C C C *