Int. J. Mol. Sci. 2019, 20, 2006
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F4 (35.0 mg) was purified by preparative HPLC (Luna C18, mobile phase H2O + 0.1% FA/CH3CN
+ 0.1% FA, isocratic elution 60:40 during 6 min then linear gradient from 60:40 to 0:100 over 13 min,
flow rate 21 mL/min) to obtain (R)-3-hydroxy-13-methyltetradecanoic acid (5) (0.2 mg, tR = 26.5 min).
F5 (41.4 mg) was purified by preparative HPLC (Luna C8, mobile phase H2O + 0.1% FA / CH3CN +
0.1% FA, isocratic elution 40:60 during 6 min then linear gradient from 40:60 to 0:100 over 13 min,
flow rate 21 m/min) to obtain (R)-2-hydroxy-13-methyltetradecanoic acid (1) (3.7 mg, tR = 14.0 min),
(R)-3-hydroxy-14-methylpentadecanoic acid (2) (1.5 mg, tR = 15.3 min), (S)-β-hydroxypalmitic acid (3)
(1.9 mg, tR = 15.6 min) and 9Z-hexadecenoic acid (7) (0.4 mg, tR = 21.5 min). F6 (258.0 mg) was purified
by preparative HPLC (Luna C8, mobile phase H2O + 0.1% FA / CH3CN + 0.1% FA, isocratic elution
35:65 during 30 min, flow rate 21 mL/min) to obtain (R)-3-hydroxy-15-methylhexadecanoic acid (4)
(7.2 mg, tR= 15.0 min), 9Z-hexadecenoic acid (7) (30.7 mg, tR = 21.0 min), 13-methyltetradecanoic acid
(6) (62.2 mg, tR = 24.0 min) and 15-methyl-9Z-hexadecenoic acid (8) (63.8 mg, tR = 27.0 min).
20
(R)-2-hydroxy-13-methyltetradecanoic acid (1): White powder. [
α
]
= 5.6 (c = 0.5, chloroform).
−
D
1H-NMR (500 MHz, CD3OD): 4.07 (1H, dd, J = 7.4, 4.4, H-2), 1.75 (1H, m, H-3), 1.63 (1H, m, H-3), 1.52
(1H, non, J = 6.7, H-3), 1.44 (2H, m, H-4), 1.30 (14H, s, H-5 to H-11), 1.17 (2H, m, H-11), 0.88 (6H, d, J = 6.8,
H-14, H-15). 13C-NMR (500 MHz, CD3OD): 178.6 (C-1), 71.9 (C-2), 40.4 (C-12), 35.7 (C-3), 31.2–30.8 (5C,
C-6 to C-10), 30.7 (C-5), 29.3 (C-13), 28.7 (C-11), 26.3 (C-4), 23.2 (2C, C-14, C-15). HR-ESI-MS: 257.2109
([M − H]−, C15H29O3−; calc. 257.2122), 515.4294 ([2M − H]−, C30H59O6−: calc. 515.4317).
20
(R)-3-hydroxy-14-methylpentadecanoic acid (2): White powder. [
α
]
= −5.6 (c = 0.5, chloroform).
D
1H-NMR (600 MHz, CD3OD): 3.96 (1H, m, H-3), 2.42 (1H, dd, J = 15.1, 4.7, H-2), 2.34 (1H, dd, J = 15.1,
8.2, H-2), 1.52 (1H, non, J = 6.7, H-14), 1.47 (4H, m, H-4, H-5), 1.30 (14H, s, H-5 to H-12), 1.18 (2H, m,
H-13), 0.88 (6H, d, J = 6.8, H-15, H-16). 13C-NMR (600 MHz, CD3OD): 176.7 (C-1), 69.6 (C-3), 43.7 (C-2),
40.4 (C-13), 38.2 (C-4), 31.2-30.9 (6C, C-6 to C-11), 29.3 (C-14), 28.7 (C-12), 26.8 (C-5), 23.2 (2C, C-1−5,
C-16). HR-ESI-MS: 271.2274 ([M
calc. 543.4630).
−
H]−, C16H31O3−; calc. 271.2279), 543.4611 ([2M
−
H]−, C32H63O6
;
1
(S)-β-hydroxypalmitic acid (3): White powder. [α]
20 = +18 (c = 0.1, chloroform). H-NMR (600 MHz,
D
CD3OD): 3.97 (1H, m, H-3), 2.43 (1H, dd, J = 15.1, 4.7, H-2), 2.36 (1H, dd, J = 15.1, 8.2, H-2), 1.47 (4H, m,
H-4, H-5), 1.30 (20H, s, H-6 to H-15), 0.90 (3H, t, J = 7.2, H-16). 13C-NMR (600 MHz, CD3OD): 176.1
(C-1), 69.5 (C-3), 43.5 (C-2), 38.3 (C-4), 33.2 (C-14), 30.9-30.6 (8C, C-6 to C-13), 26.8 (C-5), 23.9 (C-15), 14.6
H]-, C16H31O3 ; calc. 271.2279), 543.4611 ([2M
−
H]−, C32H63O6
-
−
;
(C-16). HR-ESI-MS: 271.2274 ([M
calc. 543.4630).
−
20
(R)-3-hydroxy-15-methylhexadecanoic acid (4): White powder. [
α
]
= 20 (c = 0.1, chloroform).
−
D
1H-NMR (500 MHz, CD3OD): 3.96 (1H, m, H-3), 2.43 (1H, dd, J = 15.1, 4.7, H-2), 2.35 (1H, dd, J = 15.2,
8.2, H-2), 1.53 (1H, non, J = 6.7, H-15), 1.47 (2H, m, H-4), 1.30 (18H, s, H-5 to H-12), 1.18 (2H, m, H-14),
0.88 (6H, d, J = 6.6, H-16, H-17). 13C-NMR (500 MHz, CD3OD): 176.5 (C-1), 69.7 (C-3), 43.7 (C-2), 40.4
(C-14), 38.3 (C-4), 31.2-30.9 (7C, C-6 to C-12), 29.3 (C-15), 28.7 (C-12), 26.8 (C-5), 23.2 (2C, C-15, C-16).
HR-ESI-MS: 285.2431 ([M
571.4943).
−
H]−, C17H33O3−; calc. 285.2435), 571.4926 ([2M
−
H]
, C34H67O6−; calc.
−
20
(R)-3-hydroxy-15-methylhexadecanoic acid (4): White powder. [
α
]
= 20 (c = 0.1, chloroform).
−
D
1H-NMR (500 MHz, CD3OD): 3.96 (1H, m, H-3), 2.43 (1H, dd, J = 15.1, 4.7, H-2), 2.35 (1H, dd, J = 15.2,
8.2, H-2), 1.53 (1H, non, J = 6.7, H-15), 1.47 (2H, m, H-4), 1.30 (18H, s, H-5 to H-12), 1.18 (2H, m, H-14),
0.88 (6H, d, J = 6.6, H-16, H-17). 13C-NMR (500 MHz, CD3OD): 176.5 (C-1), 69.7 (C-3), 43.7 (C-2), 40.4
(C-14), 38.3 (C-4), 31.2-30.9 (7C, C-6 to C-12), 29.3 (C-15), 28.7 (C-12), 26.8 (C-5), 23.2 (2C, C-15, C-16).
HR-ESI-MS: 285.2431 ([M
571.4943).
−
H]−, C17H33O3−; calc. 285.2435), 571.4926 ([2M
−
H]
, C34H67O6−; calc.
−
20
(R)-3-hydroxy-13-methyltetradecanoic acid (5): White powder. [
α
]
= 15 (c = 0.1, chloroform).
−
D
1H-NMR (600 MHz, CD3OD): 3.89 (1H, s, H-3), 2.33 (1H, m, H-2), 2.24 (1H, m, H-2), 1.52 (1H, m, H-13),
1.45 (4H, s, H-4, H-5), 1.30 (12H, s), 1.18 (2H, s, H-12), 0.88 (6H, d, J = 6.6, H-14, H-15). 13C-NMR (600