TY - JOUR
T1 - Ru(II) coordination compounds of N[sbnd]N bidentate chelators with 1,2,3 triazole and isoquinoline subunits
T2 - Synthesis, spectroscopy and antimicrobial properties
AU - Kreofsky, Nicholas W.
AU - Dillenburg, Maxwell D.
AU - Villa, Eric M.
AU - Fletcher, James T.
N1 - Funding Information:
This publication was made possible by grants from the National Institute for General Medical Science (NIGMS) (5P20GM103427), a component of the National Institutes of Health (NIH), and its contents are the sole responsibility of the authors and do not necessarily represent the official views of NIGMS or NIH.
Funding Information:
This publication was made possible by grants from the National Institute for General Medical Science ( NIGMS ) ( 5P20GM103427 ), a component of the National Institutes of Health (NIH), and its contents are the sole responsibility of the authors and do not necessarily represent the official views of NIGMS or NIH. Appendix A
Publisher Copyright:
© 2019 Elsevier Ltd
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2020/2/1
Y1 - 2020/2/1
N2 - Bidentate chelators 1-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline and 3-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline were prepared from benzyl bromide and trimethylsilylethynylisoquinoline precursors using a tandem deprotection/substitution/CuAAC synthetic approach. Each chelator is capable of forming a stable 3:1 Ru(II) coordination compound, which forms as a geometric isomer mixture. These Ru(II) complexes possess unique MLCT absorbance signatures at 450/472 nm (1-isomer) and 367 nm (3-isomer) relative to their constituent chelating units. Minimum inhibitory concentration values as low as 0.4 μM are observed for Ru(II) complexes against representative Gram-positive bacteria Bacillus subtilis and Staphylococcus epidermidis. Comparing the MIC values of these isoquinoline compounds with analogous 2-(1-benzyl-1,2,3-triazol-4-yl)pyridine compounds shows a 2.5- to 40-fold improvement in potency. This study establishes that increased hydrophobicity introduced at the central chelating units of Ru(II) coordination compounds can be a useful means by which to optimize antimicrobial activity that is complimentary to the variation of peripheral substituent identity at the chelator's N1 triazole position.
AB - Bidentate chelators 1-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline and 3-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline were prepared from benzyl bromide and trimethylsilylethynylisoquinoline precursors using a tandem deprotection/substitution/CuAAC synthetic approach. Each chelator is capable of forming a stable 3:1 Ru(II) coordination compound, which forms as a geometric isomer mixture. These Ru(II) complexes possess unique MLCT absorbance signatures at 450/472 nm (1-isomer) and 367 nm (3-isomer) relative to their constituent chelating units. Minimum inhibitory concentration values as low as 0.4 μM are observed for Ru(II) complexes against representative Gram-positive bacteria Bacillus subtilis and Staphylococcus epidermidis. Comparing the MIC values of these isoquinoline compounds with analogous 2-(1-benzyl-1,2,3-triazol-4-yl)pyridine compounds shows a 2.5- to 40-fold improvement in potency. This study establishes that increased hydrophobicity introduced at the central chelating units of Ru(II) coordination compounds can be a useful means by which to optimize antimicrobial activity that is complimentary to the variation of peripheral substituent identity at the chelator's N1 triazole position.
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U2 - 10.1016/j.poly.2019.114259
DO - 10.1016/j.poly.2019.114259
M3 - Article
AN - SCOPUS:85076679286
VL - 177
JO - Polyhedron
JF - Polyhedron
SN - 0277-5387
M1 - 114259
ER -