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Chapter 21 725
Copyright © 2017 Pearson Education, Inc.
aspartame
NHCH OCH
3
H
2
NCH
CH
2
COO
−
CH
2
Cl
2
CF
3
CO
2
H
NHCH OCH
3
NHCH
CH
2
COO
−
(CH
3
)
3
CO
H
2
NCH OCH
3
2. CH
3
OH
1. SOCl
2
H
2
NCH O
−
CH
2
DCC
DCCD
H
The amino group of the N-terminal
amino acid is activated.
The carboxyl group of
the N-terminal amino
acid is activated.
methyl ester of
phenylalanine
2
NCH O
−
CH
2
COO
−
+
(CH
3
)
3
CO O OC
NHCH O
−
(CH
3
)
3
(CH
3
)
3
CO
CH
2
COO
−
C
O
C
O
C
O
C
O
C
O
NHCH O
(CH
3
)
3
CO
CH
2
COO
−
CH
2
CH
2
CH
2
C
O
C
O
C
O
C
O
C
O
C
O
C
O
C
O
C
O