RSC Advances
Paper
a
4
p
Sodium N -lauramide lysine (4d). Yield 89%; HRMS (ESI) for
q ¼
sin q=2
(4)
+
1
l
C
18
H
36
N
2
O
3
, m/z [M + H] : calcd 329.2804, found 329.2812; H
NMR (MeOD, 300 MHz): d 7.73 (s, 1H, CONH), 4.05–4.12 (m, 1H,
CHCOOH), 2.98 (t, J ¼ 6.0 Hz, 2H, CH NH ), 2.51 (t, J ¼ 1.5 Hz,
1H, COCHH), 2.17 (t, J ¼ 7.2 Hz, 1H, COCHH), 1.23–2.12 (m,
where q is the scattering angle and l is the wavelength of the
radiation (l ¼ 0.154 nm). The q range obtained with our setup
2
2
ꢁ
1
was from 0.5 to 6.5 nm
.
1
3
2
4H, CH ), 0.85 (t, J ¼ 6.6 Hz, 3H, CH ). C NMR (75 MHz,
2
3
XRD data were recorded by an ARL X'TRA X-ray diffractom-
eter at a scanning speed of 10 min
ꢀ
ꢁ1
MeOD) d 179.36 (s), 175.21 (s), 53.28 (s), 41.43 (s), 33.48 (s),
2.23 (d, J ¼ 1.5 Hz), 32.09 (s), 29.23 (dd, J ¼ 18.5, 6.0 Hz), 25.99
s), 23.25 (d, J ¼ 16.0 Hz), 22.64 (s), 13.33 (s). Elemental analysis
for C18 Na, calcd 350.25, C% calcd 61.69, found 61.64,
.
3
(
Scanning electron microscope imaging of the samples was
done using a Hitachi S-3400N II scanning electron microscope.
The samples were dried overnight in a vacuum before the
observation.
FTIR spectra were obtained with a JASCO FT/IR-660 Plus. To
obtain FTIR spectra, the gels were dried under vacuum. The
dried samples and KBr were mixed and ground to form a ne
powder under-lamp sample loading to avoid atmospheric
moisture.
35 2 3
H N O
H% calcd 10.07, found 10.11, N% calcd 7.99, found 7.98.
a
Sodium N -myristamide lysine (4e). Yield 83%; HRMS (ESI)
+
for C20
H
40
N
2
O
3
, m/z [M + H] : calcd 357.3072, found 357.3113;
1
H NMR (300 MHz, MeOD) d 4.31–4.18 (m, 1H, CHCOOH), 2.61
t, J ¼ 6.6 Hz, 2H, CH NH ), 2.31–2.10 (m, 2H, COCH ), 1.55–
(
1
2
2
2
1
3
.21 (m, 28H, CH ), 0.93 (dd, J ¼ 25.1, 7.0 Hz, 3H, CH ).
C
2
3
NMR (75 MHz, MeOD) d 178.26 (s), 174.25 (s), 55.28 (s), 41.53 (s),
6.48 (s), 32.93 (d, J ¼ 1.5 Hz), 32.01 (s), 29.53 (dd, J ¼ 18.5, 6.0
Hz), 25.99 (s), 23.25 (d, J ¼ 16.0 Hz), 22.65 (s), 13.37 (s).
Elemental analysis for C20 Na, calcd 378.29, C% calcd
3.46, found 63.50, H% calcd 10.39, found 10.42, N% calcd 7.40,
found 7.38.
The elemental analyses measurements were performed with
a Vario Micro cube (Elementar, Germany).
3
39 2 3
H N O
a
General procedure for the synthesis of N -acylation lysine
6
based derivatives(4a–4f)
a
Water (100 mL), a-octanamide-3-caprolactam (50 mmol, 12.7 g)
Sodium N -palmitamide lysine (4f). Yield 79%; HRMS (ESI)
+
and NaOH (100 mmol, 4.0 g) were added to the ask reuxing. for C H N O , m/z [M + H] : calcd 385.3385, found 385.3425;
2
2
44 2 3
1
Aer being stirred for 8 h, the solution was ltered while hot to
2
H NMR (400 MHz, D O) d 4.07 (s, 1H, CHCOOH), 2.61 (s, 2H,
remove insoluble impurities. The ltrate was cooled to room CH NH ), 2.18 (s, 2H, COCH ), 1.67–1.46 (d, J ¼ 36.4 Hz, 4H,
2
2
2
1
3
temperature then adjusted to neutral pH. Crude products were CH ), 1.20 (s, 28H, CH ), 0.78 (s, 3H, CH ). C NMR (75 MHz,
2
2
3
precipitated from water. Aer ltering, washing and drying, DMSO) d 177.22 (s), 173.19 (s), 55.79 (s), 42.82 (s), 41.11 (d, J ¼
a
1
3.7 g of sodium N -octanamide lysine was obtained.
19.6 Hz), 40.68 (s), 40.40 (s), 40.12 (s), 37.43 (s), 34.52 (s), 34.18
a
Sodium N -hexanamide lysine (4a). Yield 85.8%; HRMS (ESI) (s), 32.85 (s), 30.78–29.87 (m), 26.95 (s), 24.07 (s), 23.59 (s), 15.01
for C H N O , m/z [M + H] : calcd 245.1820, found 245.1842; (s). Elemental analysis for C H N O Na, calcd 406.32, C%
H NMR (300 MHz, D
+
1
2
24
2
3
22 43 2 3
1
2
O): d 4.25 (dd, J ¼ 8.3, 4.7 Hz, 1H, calcd 64.99, found 65.03, H% calcd 10.66, found 10.69, N%
NH ), 2.47–2.21 (m, 2H, calcd 6.89, found 6.87.
), 0.97 (t, J ¼ 6.5 Hz, 3H,
O) d 182.16–182.00 (m), 179.20 (s), for C H N O , m/z [M + H] : calcd 413.3698, found 413.3743;
CHCOOH), 2.68 (t, J ¼ 6.7 Hz, 2H, CH
2
2
a
CH
CH
5
2
CONH), 1.96–1.28 (m, 12H, CH
2
Sodium N -stearamide lysine (4g). Yield 75%; HRMS (ESI)
1
3
+
3
). C NMR (75 MHz, D
2
2
4
48 2 3
1
7.81 (s), 43.27 (s), 38.65 (s), 34.40 (d, J ¼ 5.8 Hz), 33.33 (s), 27.84
s), 25.42 (s), 24.44 (s), 16.05 (s). Elemental analysis for (t, J ¼ 6.9 Hz, 2H, CH NH ), 2.30–2.15 (m, 2H, COCH ), 1.74–
H NMR (300 MHz, MeOD) d 4.29–4.19 (m, 1H, CHCOOH), 2.61
(
2
2
2
C H N O Na, calcd 266.16, C% calcd 54.12, found 54.17, H% 1.54 (m, 6H, CH ), 1.29 (s, 30H, CH ), 0.89 (d, J ¼ 6.8 Hz, 3H,
1
2
23
2
3
2
2
1
3
calcd 8.71, found 8.74, N% calcd 10.52, found 10.48.
CH ). C NMR (75 MHz, MeOD) d 178.17 (s), 174.22 (s), 55.24
3
a
Sodium N -octanamide lysine (4b). Yield 93%; HRMS (ESI) (s), 41.52 (s), 38.37 (s), 36.49 (s), 32.94 (s), 32.00 (s), 29.90–29.23
+
for C14
H
28
N
2
O
3
, m/z [M + H] : calcd 273.2133, found 273.2199; (m), 25.99 (s), 23.10 (s), 22.65 (s), 13.35 (s). Elemental analysis
O) d 4.32 (s, 1H, CHCOOH), 3.13 (s, 2H, for C H N O Na, calcd 434.35, C% calcd 66.32, found 66.36,
1
H NMR (300 MHz, D
2
2
4
47 2 3
CH
2
NH
2
), 2.40 (s, 2H, CH
2
CONH), 2.05–1.48 (m, 16H, CH
). C NMR (75 MHz, D O) d 180.80 (s), 178.17 (s),
7.20 (s), 42.20 (s), 38.79 (s), 34.37 (s), 34.03 (s), 31.68 (d, J ¼ 15.6
2
), 0.99 H% calcd 10.90, found 10.92, N% calcd 6.45, found 6.43.
1
3
(s, 3H, CH
3
2
5
Conflicts of interest
Hz), 29.35 (s), 28.43 (s), 25.18 (s), 16.52 (s). Elemental analysis
for C H N O Na, calcd 294.19, C% calcd 57.12, found 57.18, The authors declared that they have no conicts of interest to
1
4
27 2 3
H% calcd 9.21, found 9.25, N% calcd 9.52, found 9.49.
this work.
a
Sodium N -capramide lysine (4c). Yield 90%; HRMS (ESI) for
+
1
16 32 2 3
C H N O , m/z [M + H] : calcd 301.2446, found 301.2489; H
Acknowledgements
NMR (300 MHz, D
CH NH ), 2.34 (s, 2H, CH
s, 3H, CH
2
O) d 4.22 (s, 1H, CHCOOH), 3.05 (s, 2H,
CONH), 1.72–1.42 (m, 21H, CH
). C NMR (75 MHz, D
O) d 181.36 (s), 177.44 (s), College of Biotechnology and Pharmaceutical Engineering,
2
2
2
2
), 0.95 We are grateful for the donation of lysine from Hong Xu Group,
1
3
(
3
2
5
2
7.62 (s), 42.02 (s), 38.88 (s), 34.62 (s), 34.30 (s), 32.63–31.87 (m), Nanjing Tech University. The research has been supported by
9.33 (s), 28.49 (s), 25.16 (d, J ¼ 19.6 Hz), 16.50 (s). Elemental the National Key Research and Development Program of China
31 2 3
analysis for C16H N O Na, calcd 322.22, C% calcd 59.60, found (2016YFB0301501), the National Natural Science Foundation of
59.64, H% calcd 9.69, found 9.72, N% calcd 8.69, found 8.68.
China (Grant No. 21776130), and the Jiangsu Synergetic
7592 | RSC Adv., 2019, 9, 7587–7593
This journal is © The Royal Society of Chemistry 2019