R. Ramachandran et al. / European Journal of Medicinal Chemistry 46 (2011) 1926e1934
1933
and 1605 (NeC]O and C]N stretching); 1509, 1456, 1392, 1228,
minimum inhibitory concentrations (MICs) were recorded by visual
observations after 24 h (for bacteria) and 72e96 h (for fungi except
C. albicans) of incubation. Streptomycin and Amphotericin B were
used as standards for bacterial and fungal study, respectively.
1266, 1163, 1093, 1011, 955, 834, 749, 668, 597 and 520 (other
stretching frequency). 1H NMR (
d ppm): 6.02 (bs,1H, H-2a); 5.14 (bs,
1H, H-6a); 5.50e5.68 (m, 2H, NCOCH2); 3.03 (dd, 2J5a5e ¼ 17.00 Hz),
3J5a6a ¼ 8.00 Hz, 1H, H-5a; 2.85e2.97 (m, 1H, H-3a); 2.68 (m, 1H, H-
5e); 1.50e1.58 (m, 2H, CH2 CH3); 0.88, t, 2H (J ¼ 7.25 Hz, CH2 CH3);
6.89e7.53 (m, 11H, aryl protons); 8.08 (d, 1H, J ¼ 8.3 Hz, H-c proton
Acknowledgements
of benzotriazole). 13C NMR (
d
ppm): 55.763 (C-2); 54.759 (C-6);
We thank NMR Research Centre, Indian Institute of Science
Bangalore, for providing NMR facilities to record NMR spectra and
Department of Chemistry & SAIF, Indian Institute of Technology e
Madras for recording X-ray Data collection.
52.553 (C-3); 44.032 (C-5); 207.516 (C]O at C-4); 167.742 (NeC]
O); 163.510 & 161.061 (C-20000 and C-60000); (146.185 (C-20 and C-60
ipso)); 136.185, 133.546, 130.733, 129.328, 128.289, 128.070,
127.572, 124.281, 120.282, 116.409, 116.200, 115.952, 115.737,
115.422, 109.805 (other aryl carbons); 56.736 (NeCOCH2); 23.222
(CH2 at CH2 CH3); 11.476 (CH3 at CH2 CH3).
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