D. Sriram et al. / Bioorg. Med. Chem. Lett. 16 (2006) 2982–2985
2985
Table 3. In vivo activity data of 3d and gatifloxacin against
Mycobacterium tuberculosis in mice
Acknowledgments
The authors are thankful to University Grants Commis-
sion [F.30-266/2004(SR)] and Council of Scientific and
Industrial Research [01 (1979)/05/EMR/-II], New Delhi,
India, for their financial assistances. This work was also
supported by grants from Fondation pour la Recherche
Compound
Lungs Spleen
(log CFU SEM) (log CFU SEM)
Control
7.88 0.22
4.26 0.19
Gatifloxacin (50 mg/kg) 5.82 0.18
8.84 0.21
5.08 0.31
6.14 0.12
3d (50 mg/kg)
´
Medicale and from the Institut National de la Sante
et de la Recherche Medicale (U655).
´
´
onto 7H10 agar plates. Cultures were incubated at 37 °C
in ambient air for 4 weeks prior to counting. Bacterial
counts were measured and compared with the counts
from negative (untreated) controls (Mean culture-form-
ing units (CFU) in lung: 7.88 and in spleen: 8.84). Com-
pound 3d decreased the bacterial load in lung and spleen
tissues with 3.62- and 3.76-log10 protections, respective-
ly, and was considered to be promising in reducing bac-
terial count in lung and spleen tissues. When compared
to gatifloxacin at the same dose level 3d decreases the
bacterial load with 1.56- and 1.06-log10 protections in
lung and spleen tissues, respectively.
References and notes
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nyl]-4-oxoquinoline-3-carboxylic
acid
(3d):
Yield:
82.9%; mp: 228 °C; IR (KBr) : 3010, 2860, 2846, 1740,
1
1640, 1620, 1506, 1236, 1125 cm; H NMR (DMSO-d6) d
(ppm): 0.28–0.53 (m, 4H, cyclopropyl-H), 1.2 (s, 3H, CH3
of piperazine), 1.4 (m, 1H, cyclopropyl-H), 2.6–3.4
(m, 7H, -piperazine-H), 3.73 (s, 3H, methoxy), 4.2 (s,
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10.02 (s, 2H, CONH2, D2O exchangeable), 10.82 (s, 1H,
NH, D2O exchangeable), 14.86 (br s, 1H, COOH);
Calculated for C29H30 F N7O6: C, 58.88; H, 5.11; N,
16.57. Found: C, 59.01; H, 5.09; N, 16.49.
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