J. Lv et al. / European Journal of Medicinal Chemistry 43 (2008) 19e24
23
1
C 70.86, H 4.43, N 7.56; ESI-MS m/z 558.19 [M ꢁ H]ꢁ; H
5.3. Crystal data collection and processing of
compound 2a
NMR (CDCl3, 300 MHz) d: 8.43e8.40 (d, J ¼ 7.8 Hz, 2H),
8.20e8.04 (m, 6H), 7.55e7.48 (m, 1H), 7.32e7.27 (m, 8H),
5.94e5.89 (m, 2H), 5.70e5.66 (m, 2H), 3.55e3.33 (m, 4H);
13C NMR (CDCl3, 75 MHz) d: 166.3, 164.5, 149.7, 140.0,
139.7, 139.2, 134.5, 131.1, 129.2, 128.9, 128.2, 127.5,
126.3, 125.4, 124.1, 78.3, 56.5, 38.4; IR (KBr); n (cmꢁ1):
3319.5, 3250.0, 3096.4 2922.7, 2863.3, 1723.4, 1657.1,
1536.4, 1496.7, 1439.9, 1339.1, 1292.6, 1247.2, 1179.8,
1149.0, 1099.8, 1038.8, 993.9, 840.1, 764.7, 748.9.
Crystals of compound 2a are monoclinic with space group
P21. The intensity data for the X-ray crystallographic deter-
mination of 2a were collected at 294(2) K on a Bruker
SMART CCD area-detector diffractometer with Mo Ka,
˚
l ¼ 0.71073 A. Corrections were made for Lorentz and Polar-
ization factors as well as for absorption (numerical).
Structures were solved with direct method using SHELX-97
and were refined by full matrix least-squares method on F2
with SHELXL-97. Non-hydrogen atoms were refined with
anisotropy thermal parameters. All hydrogen atoms were
geometrically fixed and allowed to refine using a riding
model. The crystal data and structure refinement parameters
for compound 2a are given in Table 1.
5.2.4. Compound 2d
Yield: 18%; m.p. > 300 ꢀC; [a]D20 þ111.7 (c 0.6, CH2Cl2);
anal. calcd. for C34H26N2O6: C 73.12, H 4.66, N 5.02; found
1
C 73.14, H 4.67, N 5.00; ESI-MS m/z 559.09 [M þ H]þ; H
NMR (CDCl3, 300 MHz) d: 8.47 (s, 1H), 7.92e7.89 (d,
J ¼ 7.5 Hz, 2H), 7.83e7.80 (d, J ¼ 7.5 Hz, 3H), 7.70 (s,
2H), 7.32e7.27 (m, 8H), 6.59e6.56 (d, J ¼ 8.7 Hz, 2H),
6.00e5.97 (m, 2H), 5.86e5.84 (m, 2H), 3.43e3.19 (m, 4H);
13C NMR (CDCl3, 75 MHz) d: 168.0, 165.5, 139.9, 139.6,
135.7, 133.7, 131.2, 130.5, 129.4, 127.1, 128.9, 128.5,
127.9, 125.4, 124.4, 123.7, 77.7, 57.1, 37.2; IR (KBr); n
(cmꢁ1): 3339.5, 3270.5, 3044.9, 2959.1, 1718.7, 1647.0,
1529.4, 1475.9, 1352.1, 1235.7, 1132.7, 1096.6, 1076.5,
1038.6, 909.1, 823.7, 734.9, 652.3.
5.4. Biological activity
5.4.1. Antibacterial studies
The in vitro antibacterial susceptibility test was done in nu-
trient broth (NB) by a two-fold serial microdilution method,
using 96-well microplates (flat bottom). Bacterial cell suspen-
sions were obtained after being incubated overnight. The
tested compounds were initially dissolved in dimethyl sulfox-
ide (DMSO) at a concentration of 6.4 mg/ml and further di-
luted with sterile growth medium. Serial two-fold dilutions
(64e0.125 mg/ml, 200 ml per well) were dispensed to each
well. After inoculation (5 ml per well) was done by use of
an automatic inoculator, plates were gently but thoroughly
shaken and were incubated at 37 ꢀC for 24 h. The inocula
size was 1e1.5 ꢂ 106 cells/ml for antibacterial assay. The
minimum inhibitory concentration (MIC) of each tested com-
pound was defined as the lowest concentration exhibiting no
visibly detectable bacteria growth. Chloramphenicol (Amresco
0230) was used as reference antibacterial agent. Suitable sol-
vent control (DMSO), positive growth control, and standard
drug control were also run simultaneously. All assays were
performed in triplicate.
5.2.5. Compound 2e
Yield: 26%; m.p. > 300 ꢀC; [a]D20 þ170.8 (c 0.4, CH2Cl2);
anal. calcd. for C31H23N3O6S: C 65.84, H 4.06, N 7.40; found
1
C 65.83, H 4.03, N 7.45; ESI-MS m/z 566.09 [M þ H]þ; H
NMR (CDCl3, 300 MHz) d: 8.08e8.05 (d, J ¼ 7.5 Hz, 2H),
7.98e7.93 (m, 1H), 7.73 (s, 2H), 7.70e7.67 (d, 2H), 7.46e
7.30 (m, 8H), 5.96e5.91 (m, 2H), 5.54e5.52 (d, J ¼ 5.3 Hz,
2H), 3.50e3.30 (m, 4H); 13C NMR (CDCl3, 75 MHz) d:
164.8, 161.1, 151.1, 139.8, 139.3, 138.8, 138.1, 134.5,
133.6, 129.5, 128.0, 125.4, 124.6, 77.7, 55.7, 37.6; IR
(KBr): n (cmꢁ1) ¼ 3418.1, 3255.4, 3046.1, 2922.7, 2878.4,
1723.4, 1657.2, 1536.5, 1496.7, 1459.1, 1439.9, 1339.9,
1247.2, 1208.9, 1099.8, 840.1, 748.9.
5.4.2. Antifungal studies
In vitro antifungal activity of the compounds was measured
by standard broth microdilution methods of the US National
Committee for Clinical Laboratory Standards for yeasts [18]
and filamentous fungi [19]. RPMI 1640 (Gibco 31800022)
which had been buffered to pH 7.0 with 0.165 M morpholino-
propanesulfonic acid (Sigma) was used as the assay medium.
Freshly grown fungi on slopes of saturated dextrose agar (log-
arithmic phase) were suspended with physiological saline, and
the cell concentration was adjusted to concentration of
104 cells/ml. The test compounds were initially dissolved in
dimethyl sulfoxide (DMSO) at a concentration of 6.4 mg/ml
and further diluted with sterile growth medium. The final con-
centrations of the compounds ranged from 0.13 to 64 mg/ml.
Compounds’ solutions (100 ml) were added to each well of
a 96-well plate (Costar 3599). After inoculation (100 ml per
well, 5 ꢂ 103 cells/ml), the 96-well plates were incubated at
5.2.6. Compound 2f
Yield: 35%; m.p. > 300 ꢀC; [a]D20 þ166.5 (c 0.4, CH2Cl2);
C 68.06, H 4.29, N 5.01; ESI-MS m/z 565.15 [M þ H]þ; H
anal. calcd. for C32H24N2O6S: C 68.08, H 4.26, N 4.96; found
1
NMR (CDCl3, 300 MHz) d; 8.44 (s, 1H), 7.96e7.94 (d,
J ¼ 7.8 Hz, 2H), 7.78 (s, 2H), 7.55e7.30 (m, 9H), 6.68e
6.65 (d, J ¼ 9 Hz, 2H), 6.00e5.90 (m, 2H), 5.64e5.59 (m,
2H), 3.65e3.14 (m, 4H); 13C NMR (CDCl3, 75 MHz)
d 166.7, 161.1, 139.7, 139.2, 137.6, 135.0, 134.5, 130.2,
129.7, 129.6, 128.2, 126.4, 125.6, 125.4, 77.7, 55.5, 37.4; IR
(KBr): n (cmꢁ1) ¼ 3456.9, 3250.0, 3054.3, 2973.6, 1722.7,
1650.3, 1538.5, 1500.3, 1459.0, 1336.9, 1247.2, 1208.0,
1134.3, 1096.7, 1030.4, 960.1, 880.1, 836.8, 823.6, 763.7,
756.0.