Table 2 ¹H (400 MHz) and ¹³C (100 MHz) NMR data of 2 in DMSO-d₆^a

L-Ala

1

CO

172.6

–

2

CH

48.4

4.22 m

3

CH₃

17.8

1.20 d (7.1)

NH

–

7.89 br d (6.9)

L-Glu

1

CO

171.3

–

2

CH

52.5

4.19 m

3

CH₂

26.7

1.75 m, 1.93 m

4

CH₂

30.3

2.22 m, 2.22 m

5

COOH

174.4

–

NH

–

8.18 d (7.2)

L-Asn

1

CO

171.1

–

2

CH

49.6

4.50 dt (7.4, 5.6)

3

CH₂

36.8

2.65 dd (15.5, 5.6), 2.73dd (15.5, 5.6)

4

CONH₂

172.3

–

NH

–

8.12 br d (7.4)

CONH₂

–

7.03 br s, 7.54br s

L-Ser

1

CO

170.2^a

2

CH

57.0

4.11 q (5.4)

3

CH₂

60.9

3.68 m, 3.68 m

NH

–

8.15 br s

L-Ser

1

CO

170.1^a

2

CH

56.3

4.27 m

3

CH₂

61.2

3.64 m, 3.64 m

NH

–

8.21 br s

L-Ser

1

CO

170.1^a

–

2

CH

55.1

4.36 dt (7.8, 5.6)

3

CH₂

61.8

3.65 m, 3.65 m

NH

–

7.75br d (7.8)

D-allo-Thr

1

CO

170.0^a

–

2

CH

58.4

4.25 m

3

CH

66.5

3.93 m

4

CH₃

19.6

1.07 d (6.3)

NH

–

7.93br d (8.8)

Gly

1

CO

168.8

–

2

CH₂

40.9

3.78dd (17.3, 5.5), 3.87dd (17.3, 5.5)

NH

–

7.96br t (5.5)

HMHDA

1

CO

169.4

–

2

CH₂

36.9

2.32 m, 2.35 m

3

CH

75.4

5.04 m

4

CH

35.8

1.71 m

5

CH₂

31.7

1.03 m, 1.33 m

6

CH₂

26.4

1.22 m, 1.31 m

7–13

CH₂

28.7–29.2

1.22 m–1.28 m

14

CH₂

31.3

1.24 m, 1.24 m

15

CH₂

22.1

1.24 m, 1.29 m

16

CH3

13.9

0.86 t (6.6)

17

CH₃

14.6

0.83 d (6.6)