          8—19                                     
                                   O
                                   ‖
  NH—CH—C—OH＋H－NH－G－C－OH
                          |                                                   |       ‖
                         G                                CH             O
     
                          O                             O
                         ‖                            ‖
→NH—G—C—NH—CH—C—OH＋HO    COH
                                                                           |
                                                                                       CH       O
                                                                                         |         ‖
   NH—CH—O—－OH＋H－NH—CH—C—OH
                               |         ‖                                            |
                             CH      C                                           CH                           
                              CH        
                             O                             O
                            ‖                            ‖
→NH—CH—C—NH—CH—C—OH＋HO
                   |                               |
                 CH                          CH
                                                   |
                                                 CH          
                                |
                              COH
                                             
             O                                            O
            ‖                                            ‖
NH—CH—COH＋H－NH－CH－COH
             |                                                |
           CH                                           CH
             |
           CH
             |                                  
          COOH  
     
NH—CH—O—NH—CH—C—CH＋HO
              |          |                    |          |
          CH       C                 CH      O
              |
           CH             
     |
  COOH
                                                                                              
                      O                              O
             |        ‖                    |        ‖
NH—CH—C—NH—CH—C—OH
                         －CH     －NH                －CHCHCOOH      NH     
                                     9—2           
                                                                                          
                                             
                                            
                                            
                                                          
                                           O                     
                                           ‖
    —N—C—C—          
                       O                             O               O                              O
                       ‖                            ‖              ‖                            ‖
NH—CH—C—NH—CH—C—G—C—NH—CH—C 
              |                               |                   |                             |
             G                             G              NHCH                     G
                                                    
                                                        9—8              f     sanger      1945  1955                       1958                                                                                                                 
       Gly     Ala     law    Jeu     lle      Asn      Gln     Lys     Arg      Ser      Tnr     cys     phe       Tyr      His     pro         
                                                    300                                                300                                                                        
                                   9—8                                                    