1670
S. K. Mamidyala et al. / Bioorg. Med. Chem. Lett. 23 (2013) 1667–1670
Table 1
Biological assay results
Compounds
Vancomycin
12a
13a
14a
12b
13b
14b
12c
13c
14c
12d
13d
14d
G-positive (MIC
S. aureusa
MRSAb
l
1
2
1
g/mL)
>128
>128
>128
64
64
64
>128
>128
>128
>128
>128
>128
>128
128
128
64
64
128
>128
64
128
16
16
16
16
16/32
128
>128
>128
>128
16
16
32
32
64
128
S. aureusc
Cytotoxicity (CC50 lM)
HEK293
HepG2
Nd
Nd
>100
>100
97.0
71
>100
>100
>100
>100
65
79
65
71
93
104
38
25
35
35
119.2
117
52
30
40
38
a
b
c
ATCC25923.
ATCC43300.
NRS 19 (GISA, glycopeptide-intermediate S. aureus).
bacteria. The compounds containing carbon–carbon single bond
linker with free carboxylic acid and phenolic group showed 16–
128 lg/mL activities against Gram-positive bacteria. The cytotoxic-
of biological assays) associated with this article can be found, in
ity of the compounds was evaluated against HepG2 and HEK293
cell lines and is detailed in the Supplementary data. Compared to
o-anisic acid derivatives the substituted o-anisic acid derivatives
gave no significant improvement in antimicrobial activities but
were found to be more cytotoxic (Table 1).
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The authors are thankful to National Health and Medical Re-
search Council (NHMRC) for the financial support in terms of fund-
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Antimicrobial Resistance in Staphylococcus aureus (NARSA) pro-
gram:
supported
under
NIAID,
NIH
Contract
HHSN272200700055C.
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Supplementary data
Supplementary data (experimental details for the synthesis of
new compounds, analytical data including NMR spectra and details