J Fluoresc (2011) 21:991–1000
999
purified by column chromatography on silica gel [eluent:
CHCl3/CH3CH2OH = 30:1 (v/v)]. The pure product was
obtained as a pale yellow solid.
8.0 Hz, 2H, Ar–H), 7.79 (d, J=9.6 Hz, 2H, Ar–H), 7.64
(d, J=8.1 Hz, 2H, Ar–H), 7.22 (d, J=7.6 Hz, 2H, Ar–H),
7.19 (d, J=7.2 Hz, 2H, Ar–H), 7.17−7.13 (t, J=4.8 Hz, 2H,
Ar–H), 6.55 (s, 2H, OH), 4.12 (d, J=8.0 Hz, 4H, Ar-CH2),
3.88 (s, 4H, CH2), 3.03–2.95 (m, 4H, CH2 ), 2.79−2.70 (m,
4H, CH2 ), 2.38 (s, 2H, NH), 1.44 (s, 18H, CH3), 13C NMR
(CDCl3): δ=174.03, 153.59, 153.31, 134.99, 133.96,
133.44, 133.17, 132.54, 131.06, 130.86, 130.58, 129.91,
128.71, 127.53, 126.62, 126.01, 125.93, 125.85, 125.73,
124.58, 74.09, 58.39, 58.49, 39.89, 24.92 ppm. ESI-MS:
m/z (%) =767. [M+Na]+. C40H52N6O8: calcd. C 64.50, H
7.04, N 11.28; found C 64.29, H 7.09, N 11.19;
S-1a: yield: 77%; ½aꢁ 20 ¼ ꢀ27:96(c=0.05, CHCl3); R-
D
1a: yield: 79%; ½aꢁ 20 ¼ þ35:42(c=0.05, CHCl3). IR (film,
D
cm−1): υ 3432, 3353, 3259, 3216, 3061, 1640, 1271, 1196,
1
1074, 1049, 822, 748. H NMR (CDCl3) δ=9.35 (s, 2H,
CONH), 7.94 (d, J=8.0 Hz, 2H, Ar–H), 7.91(d, J=9.8 Hz,
2H, Ar–H), 7.74 (d, J=7.6 Hz, 2 H, Ar–H), 7.63 (d, J=
7.8 Hz, 2 H, Indole-NH), 7.52(d, J=8.1 Hz, 2 H, Indole),
7.35 (d, J=7.2 Hz, 2H, Ar–H), 7.23−7.19 (m, 4H, Ar–H),
7.16−7.11 (m, 6H, Ar–H), 6.72 (s, 2H, OH), 6.45 (s, 2H,
Boc-NH), 5.53(s, 2 H,NC*HCO), 4.65 (d, J=8.0 Hz, 4H,
Ar-CH2), 3.38 (m, 4H, Indole-CH2), 3.12–3.21 (m, 8H,
NCH2C), 2.43 (s, 2H, NH), 1.42(s, 18 H, Boc-tBu) ppm;
13C NMR (CDCl3): δ=28.6, 34.4, 38.5, 39.3, 43.8, 57.4,
76.1, 82.1, 115.4, 119.6, 121.4, 122.6, 123.8, 124.3, 125.6,
126.2, 126.8, 127.6, 128.6, 127.9, 129.1,132.9, 140.2,
142.1, 142.6, 149.7, 151.0, 155.6, 169.6, 172.7 ppm, ESI-
Preparation of samples for fluorescence measurement
All solutions were prepared using volumetric syringes,
pipettes, and volumetric flasks. The tetrabutylammonium
salts were prepared by adding 1 equiv. of tetrabutylammonium
hydroxide in methanol to a solution of the corresponding
carboxylic acid in methanol and stock solutions of the salts
were prepared in CHCl3. The resulting syrup was dried under
high vacuum for 24 h, analyzed by NMR spectroscopy, and
stored in a desiccator. The compounds S-1a, S-1b, R-1a,
R-1b and S-7 were prepared as stock solutions in CHCl3.
The test solutions were prepared by adding different volumes
of anion solution to a series of test tubes and then the same
amount of stock solution of the host compound was added to
each of the test tubes and diluted to 3.0 mL with CHCl3.
After being shaken for several minutes, the test solutions
were analyzed immediately.
+
MS m/z: 1025 (M+Na) . C58H66N8O8: calcd. C 69.44, H
6.63, N 11.17; S-1a: found C 69.21, H 6.71, N 11.01; R-1a:
found C 69.18, H 6.72, N 11.04;
S-1b: yield: 72.4%; ½aꢁ 20 ¼ ꢀ25:62 (c=0.05, CHCl3).
D
R-1b: yield: 78.2%; ½aꢁ 20 ¼ þ32:09 (c=0.05, CHCl3). IR
D
(film, cm−1): υ 3434, 3357, 3259, 3218, 3065, 1642, 1270,
1
1196, 1078, 1049, 822, 747. H NMR (CDCl3) δ (ppm):
9.32 (s, 2H, CONH), 7.91 (d, J=8.0 Hz, 2H, Ar–H), 7.88(d,
J=9.8 Hz, 2H, Ar–H), 7.72 (d, J=7.6 Hz, 2 H, Ar–H), 7.60
(d, J=7.8 Hz, 2 H, Indole-NH), 7.56(d, J=8.1 Hz, 2 H,
Indole), 7.39 (d, J=7.2 Hz, 2H, Ar–H), 7.21−7.15 (m, 4H,
Ar–H), 7.14−7.08 (m, 6H, Ar–H), 6.72 (s, 2H, OH), 6.46
(s, 2H, Boc-NH), 5.51(s, 2 H,NC*HCO), 4.62 (d, J=
8.0 Hz, 4H, Ar-CH2), 3.36 (m, 4H, Indole-CH2), 3.12–3.21
(m, 8H, CH2), 2.43 (s, 2H, NH), 2.22−2.11 (m, 4H, CH2),
1.42(s, 18 H, Boc-tBu), 13C NMR (CDCl3): δ=28.6,29.9,
34.6, 38.7, 39.7, 43.9, 57.6, 76.4, 82.0, 115.2, 119.3, 121.1,
122.2, 123.2, 124.1, 125.8, 126.0, 126.7, 127.9, 128.1,
128.9, 129.4,132.6, 140.5, 142.6, 142.9, 149.3, 151.2,
155.1, 169.0, 172.1 ppm, ESI-MS m/z: 1053 (M+Na+).
C60H70N8O8: calcd. C 69.88, H 6.84, N 10.87; S-1b: found
C 69.61, H 6.89, N 10.75; R-1b: found C 69.65, H 6.90,
N 11.72;
Job plots
Stock solutions of host S-1a and the (S)-Phe, (R)-Phe
tetrabutylammonium salts in CHCl3 system (the total
concentration of the host and guest is 1.0×10−6 mol L−1)
were freshly prepared. The receptor and Phe solutions were
added to the test tubes in ratios of 9:1, 8:2 to 0:10,
respectively. After being shaken for several minutes, the
work solution could be measured immediately.
Acknowledgments We thank the National Natural Science Foundation
for financial support (Grant No. 20872027/B0206).
Preparation and characterization of compound S-7
The preparation procedure was the same as that of S-1 or
R-1 by starting with compound 6. After workup, the crude
product was purified by column chromatography on silica
gel [eluent: CHCl3/CH3CH2OH = 50:1 (v/v)]. The pure
product was obtained as a pale yellow solid. yield: 79.6%;
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2. Sara R, Graham MK, David LT, Neil JW, Jeremy DK (2002) A
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½aꢁ 20 ¼ ꢀ68:32(c=0.05, CHCl3); IR (film, cm−1): υ 3402,
D
3092, 2969, 1679, 1529, 1268, 1234, 752. 1H NMR
(CDCl3) δ (ppm): 7.89 (s, 2H, CONH), 7.87 (d, J=