1538
Pernak J, et al. Sci China Chem August (2012) Vol.55 No.8
Table 8 The effective dose (ED50) of tested cyclamates for Lepidium sativum
Entry
11
ED50 (ppm)
8.14
Equationa)
ED50 (µM)
y = 0.8640lnx + 76.061
y = 3.9195lnx + 22.867
y = 5.3732lnx + 33.369
y = 3.9628lnx + 50.096
y = 23.859lnx – 189.95
y = 1.1509lnx + 67.266
20
2100
40
12
1014.92
22.09
13
14
0.97
2
15
23318.48
3.05
73550
6
16
a) “x” denotes concentration in ppm.
formed at the Adam Mickiewicz University, Poznan (Po-
land). The water content was determined by using an Aq-
uastar volumetric Karl-Fischer titration with Composite 5
solution as the titrant and anhydrous methanol as a solvent.
Melting points were determined by visual observation via
hot-plate apparatus.
30.5, 31.6, 32.7, 34.1, 52.9, 71.2, 89.5, 128.1, 143.3, 144.2;
Elemental analysis calcd (%) for C18H32N2O4S (372.52): C
58.03, H 8.66, N 7.52; found C 58.20, H 8.80, N 7.35.
1
1-Dodecyloxymethylpyridinium cyclamate (9): H NMR
(CDCl3) δ in ppm 0.86 (t, J = 6.7 Hz, 3H), 1.24(m, 20H),
1.58(m, 2H), 1.61 (m, 2H), 1.71(m, 1H), 1.89(m, 2H),
1.98(m, 2H), 2.11(m, 2H), 3.23(m, 1H), 3.48(m, 2H), 6.35(s,
2H), 8.19 (t, J = 7.1 Hz, 2H), 8.61(t, J = 7.7 Hz, 1H), 9.24(d,
J = 5.5 Hz, 2H); 13C NMR (CDCl3) δ in ppm 14.0, 22.5,
24.9, 25.6, 25.7, 29.2, 29.2, 29.3, 29.4, 29.5, 29.5, 29.5,
31.8, 34.0, 52.9, 71.5, 89.5, 128.2, 143.3, 146.7; Elemental
analysis calcd (%) for C24H44N2O4S (456.68) C 63.12, H
9.71, N 6.13; found C 63.31, H 9.59, N 6.05.
4.2 Synthetic procedure of cyclamates
(0.01 mol) Sodium cyclamate was dissolved in distilled
water and added to aqueous solutions containing 0.01 mol
of 1-alkoxymethylpyridinium chlorides or 1-alkylpyridin-
ium chlorides or didecyldimethylammonium chloride or
benzalkonium chloride or 3-butyl-1-methylimidazolium
chloride or 1-methyl-3-tetradecyloxymethylimidazolim
chloride. The mixture was stirred at room temperature for
24 h. The product was isolated by one of the following
methods:
Method A: The water was evaporated, and crude product
was dried under high vacuum at 50 °C. After that dry ace-
tone was added and the mixture was stirred at room temper-
ature for 24 h. The crystalline sodium chloride was removed
by filtration and the acetone was removed by distillation.
The obtained product was dried overnight in vacuum at
80 °C.
Method B: The product was extracted from the aqueous
solution with chloroform. The chloroform phase was sepa-
rated and washed with distilled water until chloride ions
were no longer detected using AgNO3. Solvent was evapo-
rated and the product was dried under vacuum overnight at
80 °C.
1-Alkoxymethylpyridinium chlorides and 1-methyl-3-
tetradecyloxymethylimidazolium chloride were prepared
according to the procedure described earlier [21, 22].
1-Alkylpyridinium chlorides, didecyldimethylammonium
chloride, benzalkonium chloride and 3-butyl-1-methylim-
idazolium chloride are commercial products, were used
without further purification.
1-Dodecylpyridinium cyclamate (11): 1H NMR (CDCl3) δ
in ppm 0.89 (t, J = 6.7 Hz, 3H), 1.19(m, 3H), 1.23(m, 18H),
1.59 (m, 2H), 1.71(m, 1H), 1.89(m, 2H), 2.01(m, 2H),
2.11(m, 2H), 3.22 (m, 1H), 3.31(m, 1H), 4.82(t, J = 7.4 Hz,
2H), 8.15 (t, J = 7.3 Hz, 2H), 8.49 (t, J = 7.8 Hz, 1H),
9.31(d, J = 5.7 Hz, 2H); 13C NMR (CDCl3) δ in ppm 14.0,
22.5, 24.9, 25.6, 26.0, 29.2, 29.3, 29.4, 29.5, 31.7, 31.8,
34.3, 52.8, 61.9, 128.3, 144.8, 145.1; Elemental analysis
calcd (%) for C23H42N2O3S (426.29) C 64.75, H 9.92, N
6.57; found C 65.07, H 10.01, N 6.94.
1-Hexadecylpyridinium cyclamate (12): 1H NMR (CDCl3)
δ in ppm 0.87 (t, J = 6.6 Hz, 3H), 1.23(m, 3H), 1.25(m, 26H),
1.59(m, 2H), 1.71(m, 1H), 1.89(m, 2H), 1.99(m, 2H),
2.12(m, 2H), 3.24(m, 1H), 3.49(s, 1H), 4.84 (t, J = 7.4 Hz,
2H), 8.12 (t, J = 7.2 Hz, 2H), 8.48 (t, J = 6.6 Hz, 1H), 9.34
(d, J = 5.5 Hz, 2H); 13C NMR (CDCl3) δ in ppm 14.0, 22.6,
25.0, 25.7, 26.0, 29.0, 29.3, 29.4. 29.6, 31.8, 31.9, 34.4,
52.8, 52.8, 128.4, 144.8, 145.4; Elemental analysis calcd (%)
for C27H50N2O3S (482.76) C 67.17, H 10.44, N 5.80, found
C 67.40, H 10.69, N 6.16.
Didecyldimethylammonium cyclamate (13): 1H NMR
(CDCl3) δ in ppm 0.88 (t, J = 6.7 Hz, 6H), 1.01(m, 3H),
1.26(m, 30H), 1.48 (m, 1H), 1.68(m, 6H), 2.08(m, 2H),
2.90(m, 1H), 3.36(s, 6H), 3.47(m, 4H), 3.98(s, 1H); 13C
NMR (CDCl3) δ in ppm 14.0, 22.6, 22.7, 25.0, 25.7, 26.2,
29.1, 29.3, 31.7, 34.4, 51.1, 52.7, 63.4; Elemental analysis
calcd (%) for C28H60N2O3S (504.853) C 66.61, H 11.98, N
5.55; found C 66.40, H 12.24, N 5.69.
1-Hexyloxymethylpyridinium cyclamate (3): 1H NMR
(CDCl3) δ in ppm 0.86 (t, J = 6.7 Hz, 3H), 1.05(m, 3H)
1.25(m, 10H), 1.46(m, 2H), 1.53(m, 1H), 1.68(m, 2H),
2.05(m, 2H), 3.11(m, 1H), 3.91(s, 1H), 6.16(m, 2H), 8.18(t,
J = 3.7 Hz, 2H), 8.59(t, J = 4.5 Hz, 1H), 9.30(d, J = 5.5 Hz,
2H); 13C NMR (CDCl3) δ in ppm 13.9, 22.4, 25.0, 25.4,
1
Benzalkonium cyclamate (14): H NMR (CDCl3) δ in
ppm 0.88 (t, J = 6.7 Hz, 3H); 1,24(m, 26H); 1,55(m, 2H);