Table 1 Resonance assignments with chemical shifts of constituents identified in 600 MHz ¹H-NMR, HSQC and HMBC spectra of Tongkat Ali (E. longifolia) methanol extract. ¹H-NMR quantification of most primary and secondary metabolites are expressed as μg/mg dry powder ± S.D (n = 3), see experimental section.

Sugars

α-Glucose (N1)

C-1

5.10 (d, J = 3.6 Hz)

94.1

–

C-2

3.36^a

73.5

74.5(C3)

C-5

3.68 (d, J = 2.4 Hz)

–

73.1(C4)

 β-Glucose (N2)

C-1

4.47 (d, J = 7.87 Hz)

97.8

–

C-2

3.13 (dd, J = 9.30, 7.87 Hz)

76.2

–

C-5

3.31^a

49.2

–

Sucrose (N3)

C-1

5.38 (d, J = 3.81 Hz)

93.5

74.5(C5), 105.1 (C2′)

C-2

3.40^a

73

74.5 (C3)

C-3

3.707^a

74.1

73.6(C2)

α-Fructofuranose (N4)

C-5

4.01 (d, J = 1.43 Hz)

73.1

71.1(C4)

β-Fructofuranose (N5)

C-3

4.10 (d, J = 8.34 Hz)

78.1

75.6 (C5)

C-6

3.71^a

63.7

72.9(C5)

Glycerol (N6)

C-1

3.58 (dd, J = 11.2, 4.8 Hz)

64.6

73.6 (C2)

C-2

3.64^a

73.8

–

Nitrogenous compounds

 Choline (N7)

N-(CH₃)₃

3.26^a

54.7

53.7 (N-CH₃), 67.3 (N-CH₂)

N-CH₂

3.8^a

67.3

53.7 (N-CH₃)

Organic and fatty acids

 Acetic acid (N8)

C-2

1.97 (s)

21.9

176 (C1)

 Succinic acid (N9)

C-2(α,β)

2.5^a

32

–

 Syringic acid (N10)

C-3/C-5

3.91^a

56

149.3 (C3/5)

C-2/C-6

7.03^a

112

120.9(C1)

 Fatty acid (N11)

C-1

–

175.1

C-2

2.33^a

35.0

25.9(C3), 30.1(C4), 175.1(C1)

C-3

1.60^a

26.0

30.1(C3)

Inner CH₂

1.28–1.30 br. S

30–31

30.8 (inner CH₂)

ω-1

1.34^a

23.5

30.2 (inner CH₂)

ω

0.9 (t, J = 7.15 Hz)

14.3

23.9(ω-1), 30.8(ω-2)

Quassinoids

 Eurycomanone (N12)

C-1

4.30 (s)

84.3

46.7 (C10), 198.8 (C2)

C-3

6.05^a

125.94

–

C-5

3.041^a

42.7

–

C6

2.056^a

26.2

130.8 (C4)

C-7

4.72^a

77.6

175.1 (C16)

C-15

4.618^a

71.8

175.1 (C16)

C-21

5.43^a

121.7

80.8 (C12), 79.34 (C20)

 13,21 Dihydroeurycomanone (N13)

C-21

1.241^a

10.8

42.5(C13), 84.3 (C12/C14)

C-13

2.178^a

–

–

Cinnamic and coumarin derivatives

 Scopoletin (N14)

C-2

6.18 (d, J = 9.4 Hz)

112.4

163.8(C1)

C-3

7.85 (d, J = 9.4 Hz)

146.1

163.8(C1), 112.7(C2)

C-8

6.71

103.3

113.8 (C4), 163.8(C1)

OCH₃

3.87

57.1

–

(E)-Cinnamaldehyde (N15)

C-1

9.66 (d, J = 7.87 Hz)

–

129.4(C2)

C-2

6.78 (dd, J = 16.0, 7.87 Hz)

–

–

C-3

7.68 (d, J = 15.5 Hz)

155

129.6 (C5/9)

C5/C9

7.68^a

130

132.6 (C 6/7/8)