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Chiaswee Hong - One of the best experts on this subject based on the ideXlab platform.
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tio2 mediated photomineralization of 2 Chlorobiphenyl the role of o2
Water Research, 2000Co-Authors: Yongbing Wang, Chiaswee HongAbstract:Abstract Photocatalytic mineralization of 2-Chlorobiphenyl (2-CB) in aqueous TiO2 suspensions was conducted under four different oxygen partial pressures (Po2) in closed reactors. The observed O2 adsorption equilibrium constant in TiO2 aqueous suspension was 0.88 (kPa)−1 based on the Langmuir–Hinshelwood rate function. Apart from the conventional electron-scavenging function, the dissolved oxygen was critical for the degradation of the hydroxyl intermediates, i.e., 2-Chlorobiphenyl-ols and biphenyl-2-ol, which are potentially toxic. Degradation of 2-CB in the irradiated H2O2 aqueous solutions under two different Po2 was also studied for comparison. For UV/H2O2, Po2 does not affect the removal of 2-CB, while reducing the Po2 from 21 to 2 kPa resulted in 35% less CO2 formation after 5 h irradiation. The similar O2-dependent destruction of the hydroxyl intermediates was also observed in the UV/H2O2 system. We propose that molecular O2 acts as a key reactant following the attack of a second ·OH radical during the ring opening in the degradation of the hydroxyl byproducts.
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effect of solution matrix on tio2 photocatalytic degradation of 2 Chlorobiphenyl
Environmental Engineering Science, 1999Co-Authors: Yongbing Wang, Chiaswee Hong, Fu FangAbstract:ABSTRACT The effects of solution matrices, i.e., pH, inorganic ions, and humic acids, on the TiO2 photocatalytic degradation of 2-Chlorobiphenyl (2-CB) were investigated. A lower solution pH was found to be favorable for the degradation in the pH range of 3 to 11. Chloride ions showed no rate effect at pH 10. The inhibition by chloride ions at pH 4 was more than that at pH 7. Carbonate/bicarbonate showed an inhibition effect on the degradation at pH 10 and pH 11. Magnesium ions inhibited the degradation under alkaline conditions, but showed no rate effect at pH 4. Humic acids were found to inhibit 2-CB degradation. The degradation rate decreased with increasing concentration of humic acid and leveled off at the concentration of 5 μg/mL. Key words: Photocatalytic degradation; titanium dioxide (TiO2); 2-Chlorobiphenyl (2-CB)
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effect of hydrogen peroxide periodate and persulfate on photocatalysis of 2 Chlorobiphenyl in aqueous tio2 suspensions
Water Research, 1999Co-Authors: Yongbing Wang, Chiaswee HongAbstract:Abstract Decomposition of 2-Chlorobiphenyl (2-CB) in the systems of UV/TiO 2 , UV/oxidant and UV/TiO 2 /oxidant (i.e. H 2 O 2 , S 2 O 8 2− and IO 4 − ), were investigated. The addition of inorganic oxidants to the UV/TiO 2 system showed no rate-enhancing effects for the degradation of 2-CB with oxidant concentration of 10 −3 and 10 −2 M and TiO 2 concentration of 25 mg/l. The negative effect of oxidants on the heterogeneous oxidation was demonstrated. Homogeneous photooxidation seems to dominate over the parallel heterogeneous process when both TiO 2 and oxidants are present.
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kinetics and products of the tio2 photocatalytic degradation of 2 Chlorobiphenyl in water
Chemosphere, 1998Co-Authors: Chiaswee Hong, Yongbing Wang, Brian BushAbstract:Abstract The light-induced degradation of 2-Chlorobiphenyl (2-CB) under simulated solar irradiation has been investigated in aqueous solutions containing TiO2 suspensions as photocatalysts. The apparent quantum yield for an initial 2-CB concentration Co = 3.8 μg/mL at the natural pH was ca. 0.005The oxidation kinetics of 2-CB follows the Langmuir-Hinshelwood kinetic model at natural pH. The primary degradation of 2-CB follows a pseudo-first-order kinetics. Several reaction intermediates were identified using GC/FTIR/MS and ion chromatography. The products at the initial stage of the reaction were seven isomers of 2-Chlorobiphenyl-ol and biphenyl-2-ol. These intermediates underwent further photocatalytic oxidation via aldehydes, ketones, and acids finally into CO2, and HCl. The formation and fate of some of these compounds under irradiation were also investigated. A reaction scheme involving hydroxyl radicals has been proposed.
Dale L Boger - One of the best experts on this subject based on the ideXlab platform.
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total syntheses and initial evaluation of ψ c s nh tpg4 vancomycin ψ c nh nh tpg4 vancomycin ψ ch2nh tpg4 vancomycin and their 4 Chlorobiphenyl methyl derivatives synergistic binding pocket and peripheral modifications for the glycopeptide antibiotics
Journal of the American Chemical Society, 2015Co-Authors: Akinori Okano, Atsushi Nakayama, Kejia Wu, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and...
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Total Syntheses and Initial Evaluation of [Ψ[C(S)NH]Tpg4]vancomycin, [Ψ[C(NH)NH]Tpg4]vancomycin, [Ψ[CH2NH]Tpg4]vancomycin, and Their (4-Chlorobiphenyl)methyl Derivatives: Synergistic Binding Pocket and Peripheral Modifications for the Glycopeptide Antibiotics
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen C. Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and 0.5–0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on d-Ala-d-Ala/d-Ala-d-Lac binding. Such analogues are likely to display especially durable antibiotic activity that is not prone to rapidly acquired clinical resistance
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Total Synthesis of [Ψ[C(NH)NH]Tpg4]Vancomycin and its (4-Chlorobiphenyl)methyl Derivative: Impact of Peripheral Modifications on Vancomycin Analogues Redesigned for Dual d‑Ala‑d‑Ala and d‑Ala‑d‑Lac Binding
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance
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total synthesis of ψ c nh nh tpg4 vancomycin and its 4 Chlorobiphenyl methyl derivative impact of peripheral modifications on vancomycin analogues redesigned for dual d ala d ala and d ala d lac binding
Journal of the American Chemical Society, 2014Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance.
Akinori Okano - One of the best experts on this subject based on the ideXlab platform.
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total syntheses and initial evaluation of ψ c s nh tpg4 vancomycin ψ c nh nh tpg4 vancomycin ψ ch2nh tpg4 vancomycin and their 4 Chlorobiphenyl methyl derivatives synergistic binding pocket and peripheral modifications for the glycopeptide antibiotics
Journal of the American Chemical Society, 2015Co-Authors: Akinori Okano, Atsushi Nakayama, Kejia Wu, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and...
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Total Syntheses and Initial Evaluation of [Ψ[C(S)NH]Tpg4]vancomycin, [Ψ[C(NH)NH]Tpg4]vancomycin, [Ψ[CH2NH]Tpg4]vancomycin, and Their (4-Chlorobiphenyl)methyl Derivatives: Synergistic Binding Pocket and Peripheral Modifications for the Glycopeptide Antibiotics
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen C. Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and 0.5–0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on d-Ala-d-Ala/d-Ala-d-Lac binding. Such analogues are likely to display especially durable antibiotic activity that is not prone to rapidly acquired clinical resistance
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Total Synthesis of [Ψ[C(NH)NH]Tpg4]Vancomycin and its (4-Chlorobiphenyl)methyl Derivative: Impact of Peripheral Modifications on Vancomycin Analogues Redesigned for Dual d‑Ala‑d‑Ala and d‑Ala‑d‑Lac Binding
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance
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total synthesis of ψ c nh nh tpg4 vancomycin and its 4 Chlorobiphenyl methyl derivative impact of peripheral modifications on vancomycin analogues redesigned for dual d ala d ala and d ala d lac binding
Journal of the American Chemical Society, 2014Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance.
Larry W Robertson - One of the best experts on this subject based on the ideXlab platform.
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4 chloro biphenyl 3 yl 2 2 2 trichloro ethyl sulfate
Acta Crystallographica Section E-structure Reports Online, 2010Co-Authors: Xueshu Li, Sean Parkin, Michael W Duffel, Larry W Robertson, Hansjoachim LehmlerAbstract:The title compound, C14H10Cl4O4S, is a 2,2,2-trichloroethyl-protected precursor of 4′-chlorobiphenyl-3-yl sulfate, a sulfuric acid ester of 4′-chlorobiphenyl-3-ol. The Caromatic—O and O—S bond lengths of the Caromatic—O—S unit are comparable to those in structurally analogous biphenyl-4-yl 2,2,2-trichloroethyl sulfates with no electronegative chlorine substituent in the benzene ring with the sulfate ester group. The dihedral angle between the aromatic rings is 27.47 (6)°.
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4′-Chlorobiphenyl-3-yl 2,2,2-trichloroethyl sulfate
International Union of Crystallography, 2010Co-Authors: Sean Parkin, Michael W Duffel, Larry W Robertson, Hansjoachim LehmlerAbstract:The title compound, C14H10Cl4O4S, is a 2,2,2-trichloroethyl-protected precursor of 4′-Chlorobiphenyl-3-yl sulfate, a sulfuric acid ester of 4′-Chlorobiphenyl-3-ol. The Caromatic—O and O—S bond lengths of the Caromatic—O—S unit are comparable to those in structurally analogous biphenyl-4-yl 2,2,2-trichloroethyl sulfates with no electronegative chlorine substituent in the benzene ring with the sulfate ester group. The dihedral angle between the aromatic rings is 27.47 (6)°
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4′-Chlorobiphenyl-4-yl 2,2,2-trichloroethyl sulfate
International Union of Crystallography, 2008Co-Authors: Hansjoachim Lehmler, Larry W Robertson, Sean ParkinAbstract:The title compound, C14H10Cl4O4S, is an intermediate in the synthesis of the PCB sulfate monoester of 4′-chloro-biphenyl-4-ol. Both the sulfate monoester and 4′-chloro-biphenyl-4-ol are metabolites of PCB 3 (4-Chlorobiphenyl). There are two molecules with different conformations in the asymmetric unit. The solid state dihedral angles between the benzene rings are 18.52 (10) and 41.84 (16)° in the two molecules, whereas the dihedral angles between the least-squares plane of the sulfated benzene ring and O—S (Ar—C—O—S) are 66.2 (3) and 89.3 (3)°. The crystal was an inversion twin with a refined component fraction of 0.44 (7)
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influence of fluoro substitution on the planarity of 4 Chlorobiphenyl pcb 3
Acta Crystallographica Section B-structural Science, 2007Co-Authors: D C Swenson, G Luthe, Larry W RobertsonAbstract:Accurate structure determinations by X-ray crystal analysis and computation using semi-empirical self-consistent field molecular orbital calculations are described and compared for five monofluorinated analogues of 4-Chlorobiphenyl, i.e. 2-fluoro-4-Chlorobiphenyl, 2'-fluoro-4-Chlorobiphenyl, 3-fluoro-4-Chlorobiphenyl, 3'-fluoro-4-Chlorobiphenyl and 4'-fluoro-4-Chlorobiphenyl. Intermolecular interactions for all monofluorinated isomers are dominated by phenyl-phenyl stacking and C-H-phenyl interactions. C-F bond lengths varied between 1.341 and 1.374 A, C-Cl between 1.733 and 1.765 A, and both correlate with electron-density differences as determined by (13)C NMR shifts. The interior ring angles at ipso-fluoro substitution increase up to 122.2-124.2 degrees due to hyperconjugation by 2p-pi-orbital overlapping, a phenomenon that was also reflected in the computer calculation. The angles of C-F and C-Cl relative to the aromatic ring for vicinal fluoro- and chloro substituents show an attraction, not a repulsion, between the adjacent F and Cl substituents. This finding is explained on the basis of electron donor and acceptor properties. The dihedral angles of ortho-substituted biphenyls show that monofluoro substitution results in slightly smaller increases compared with chlorine, while additional ortho-fluorination results in little further change in the dihedral angle. In contrast, ortho-chlorination strongly decreases the co-planarity. This is likely to be due to interior ring-angle distortion and the size of the halogen substituent. Fluoro substitution does indeed affect the planarity of the PCB3 analogues, but these effects are minor compared with chloro substitution. Fluorine tagging offers promise for use in in vitro and in vivo studies. Differences in computational versus measured data emphasize the need to use a variety of methods to ascertain the true nature of the physical properties of a compound.
Alex W Schammel - One of the best experts on this subject based on the ideXlab platform.
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total syntheses and initial evaluation of ψ c s nh tpg4 vancomycin ψ c nh nh tpg4 vancomycin ψ ch2nh tpg4 vancomycin and their 4 Chlorobiphenyl methyl derivatives synergistic binding pocket and peripheral modifications for the glycopeptide antibiotics
Journal of the American Chemical Society, 2015Co-Authors: Akinori Okano, Atsushi Nakayama, Kejia Wu, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and...
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Total Syntheses and Initial Evaluation of [Ψ[C(S)NH]Tpg4]vancomycin, [Ψ[C(NH)NH]Tpg4]vancomycin, [Ψ[CH2NH]Tpg4]vancomycin, and Their (4-Chlorobiphenyl)methyl Derivatives: Synergistic Binding Pocket and Peripheral Modifications for the Glycopeptide Antibiotics
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Erick A Lindsey, Alex W Schammel, Yiqing Feng, Karen C. Collins, Dale L BogerAbstract:Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral l-vancosaminyl-1,2-d-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral Chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual d-Ala-d-Ala/d-Ala-d-Lac binding. Their collective assessment indicates that combined binding pocket and Chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 and 0.5–0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on d-Ala-d-Ala/d-Ala-d-Lac binding. Such analogues are likely to display especially durable antibiotic activity that is not prone to rapidly acquired clinical resistance
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Total Synthesis of [Ψ[C(NH)NH]Tpg4]Vancomycin and its (4-Chlorobiphenyl)methyl Derivative: Impact of Peripheral Modifications on Vancomycin Analogues Redesigned for Dual d‑Ala‑d‑Ala and d‑Ala‑d‑Lac Binding
2015Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance
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total synthesis of ψ c nh nh tpg4 vancomycin and its 4 Chlorobiphenyl methyl derivative impact of peripheral modifications on vancomycin analogues redesigned for dual d ala d ala and d ala d lac binding
Journal of the American Chemical Society, 2014Co-Authors: Akinori Okano, Atsushi Nakayama, Alex W Schammel, Dale L BogerAbstract:The total synthesis of two key analogues of vancomycin containing single-atom exchanges in the binding pocket (residue 4 amidine and thioamide) are disclosed as well as their peripherally modified (4-Chlorobiphenyl)methyl (CBP) derivatives. Their assessment indicates that combined pocket amidine and CBP peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies (MIC = 0.06–0.005 μg/mL) against both vancomycin-sensitive and -resistant bacteria and likely benefit from two independent and synergistic mechanisms of action. Like vancomycin, such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance.