578
Y. Ge et al.
Table 2 Antibacterial activities (MICs, μg ml−1) of thiosemicarbazones
1a-1m against three drug-resistant strains expressing β-lactamases (a),
and MICs of 1a and 1f (16 μg ml−1) synergize three antibiotics (b)
synergistic antimicrobial effect with ampicillin, cefazolin and
meropenem on E. coli producing NDM-1 and EC08, resulting
in MICs of 4-32-, 4-64-, and 4-16-fold decrease, respectively.
a
Acknowledgements This research was funded by the Grants
(22077100 and 2019KW-068 to K.W.Y) from the National Natural
Science Foundation of China and Shaanxi Province International
Cooperation Project and grant (17JS007 to L.Z.) from the Shaanxi
Education Commission, China.
compd. E.coli- EC01 EC08 compd. E.coli- EC01 ECO8
NDM-1
NDM-1
1a
1b
1c
1d
1e
1f
64
64
64
1h
1i
1024
256
64
1024 1024
256
256
128
256
32
256
128
128
256
64
256
256
128
256
32
256
64
256
64
1j
Compliance with ethical standards
1k
1l
32
64
32
256
32
256
128
256
64
Conflict of interest The authors declare no competing interests.
1m
Publisher’s note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations.
1g
256
256
256
cefazolin 256
20000 5000
b
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Thirteen thiosemicarbazones (1a-1m) were synthesized and
characterized by 1H and 13C NMR and MS. Biological assays
revealed that these compounds inhibited NDM-1, with an
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