Ethambutol–sugar hybrids as potential inhibitors of mycobacterial cell-wall biosynthesis

Reynolds, Robert C.; Bansal, Namita; Rose, J. D.; Friedrich, Joyce D.; Suling, William J.; Maddry, Joseph A.

doi:10.1016/s0008-6215(99)00069-5

Cited by 45 publications

(13 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Ethambutol, ein natürlich vorkommender Inhibitor der Arabinosyltransferase,96 wird in der Behandlung der Tuberkulose verwendet und seine antibiotische Wirkung ist spezifisch für Mycobakterien (Schema ). Da Ethambutol nur relativ schwach aktiv ist und eine Reihe von Nebenwirkungen hat, wurden synthetische Inhibitoren der Arabinosyltransferase untersucht, einschließlich einiger Ethambutol‐Zucker‐Hybride97 und aza‐Analoga der Arabinofuranose 98. Leider waren die Verbindungen weniger aktiv als das Ethambutol.…”

Section: Antibiotika Die Die Zellhülle Angreifenunclassified

Plasmonic Enhancement of a Photocycloreversion Reaction of a Diarylethene Derivative Using Individually Dispersed Silver Nanoparticles

2012

View full text Add to dashboard Cite

The fabrication of silver nanoparticles covered with polymers with a well-defined core-shell structure and the quantitative evaluation of the plasmonic enhancement effect on a photochemical reaction in the vicinity of these silver nanoparticles individually dispersed in a medium are described. The photocycloreversion reaction of a diarylethene polymer in the vicinity of silver nanoparticles was enhanced by 2-6 times relative to the reaction without the nanoparticles. The promotion of the photocycloreversion reaction is due to enhancement of the electromagnetic field near the surface of the silver core.

show abstract

Section: Antibiotika Die Die Zellhülle Angreifenunclassified

Plasmonic Enhancement of a Photocycloreversion Reaction of a Diarylethene Derivative Using Individually Dispersed Silver Nanoparticles

2012

View full text Add to dashboard Cite

show abstract

“…Staudinger reaction of azide 6 with Me 3 P in THF [30], followed by treatment of the crude iminophosphorane 6A with aldehyde 10, generated an imine [30] [31] that was reduced in situ with NaBH 3 CN [32] to yield 70% of the A*[n]U dinucleoside 15 (Scheme 3). Debenzoylation of 15 with MeONa in MeOH gave the silyl ether 16 (90%) that was desilylated by treatment with (HF) 3 · Et 3 N in THF [33] to yield 88% of the alcohol 17.…”

mentioning

confidence: 99%

Oligonucleotide Analogues with Integrated Bases and Backbones. Part 24

Chiesa

Shvoryna

Bernet

et al. 2010

Helvetica Chimica Acta

View full text Add to dashboard Cite

Inspection of Maruzen models and force-field calculations suggest that oligonucleotide analogues integrating backbone and bases (ONIBs) with an aminomethylene linker form similar cyclic duplexes as the analogous oxymethylene linked dinucleosides. The self-complementary adenosine-and uridinederived aminomethylene-linked A*[n]U dinucleosides 15 -17 were prepared by an aza-Wittig reaction of the aldehyde 10 with an iminophosphorane derived from azide 6. The sequence-isomeric U*[n]A dinucleosides 18 -20 were similarly prepared from aldehyde 3 and azide 12. The N-ethylamine 5, the acetamides 7 and 14, and the amine 13 were prepared as references for the conformational analysis of the dinucleosides. In contradistinction to the results of calculations, the N-ethylamine 5 exists as intramolecularly H-bonded hydroxyimino tautomer. The association in CDCl 3 of these dinucleosides was studied by 1 H-NMR and CD spectroscopy. The A*[n]U dinucleosides 16 and 17 associate more strongly than the sequence isomers 19 and 20; the cyclic duplexes of 16 form preferentially Watson -Crick-type base pairs, while 17, 19, and 20 show both Watson -Crick-and Hoogsteen-type base pairing. The cyclic duplexes of the aminomethylene-linked dinucleosides prefer a gg-orientation of the linker. No evidence was found for an intramolecular H-bond of the aminomethylene group. The CD spectra of 16 and 17 show a strong, those of 19 a weak, and those of 20 almost no temperature dependence.Helvetica Chimica Acta -Vol. 93 (2010) 668 2010 Verlag Helvetica Chimica Acta AG, Zürich 1 ) Conventions for abbreviated notation: The substitution at C(6) of pyrimidines and C(8) of purines is denoted by an asterisk (*); for example, A* and U* for thiomethylated adenosine and uridine derivatives, respectively. The moiety x linking C(6)ÀCH 2 or C(8)ÀCH 2 of unit II and C(5') of unit I is indicated in square brackets, i.e., [c] for a C-, [o] for a O-, [n] for a N-, and [s] for a S-atom.

show abstract

“…The complex cell wall structure of M. tuberculosis , consisting of a dense network of cross‐linked sugar residues esterified with mycolic acid at their ends, contribute to its defence against TB 5. There have been some reports of interference in the defence mechanism by sugar derivatives, either in the form of imino alditols6 or as appendages to known drugs 7. With the resurgence of multi‐drug resistant Mycobacterium the present therapy is proving ineffective and there is a need to explore completely new chemical entities which can work as antimycobacterial agents.…”

mentioning

confidence: 99%

Tandem mass spectra of ammonium ion, metal ion and ligated metal ion adducts of acyclic sugar derivatives

Madhusudanan

Kumar

Pathak

et al. 2003

Rapid Comm Mass Spectrometry

View full text Add to dashboard Cite

The tandem mass (MS/MS) spectra of ammonium ion, metal ion and ligated metal ion adducts of chain-extended acyclic nitro-containing deoxyglucose and deoxygalactose derivatives have been studied. The ammonium adducts fragment primarily by elimination of ammonia followed by acetic acid, thus not giving much structural information. In contrast, cationization of these compounds by metal ions and ligated metal ions gave structurally informative and useful fragment ions on MS/MS. The metal ions and ligated metal ions play an important role in controlling and directing fragmentation. Retro-aldol fragmentation is facilitated by metal ions such as Li(+), Na(+), Ag(+) and Cu(+), whereas the adducts with higher alkali metal ions such as Rb(+) and Cs(+) fragment to give only the corresponding metal ions. The divalent metal ions such as Cu(2+) and Ba(2+) also induce retro-aldol fragmentation. However, the charge is carried by the aldehyde fragment in the case of Cu(2+) adducts, whereas the nitroalkane fragment carries the charge in the case of Ba(2+) adducts. Ligated metal ions such as ZnCl(+), CuCl(+), InCl(2) (+) and BaCl(+) also behave similarly and induce retro-aldol fragmentation in these acyclic sugars. Both the metal ion and ligated metal ion adducts can fragment by elimination of metal-containing neutral molecules.

show abstract

Ethambutol–sugar hybrids as potential inhibitors of mycobacterial cell-wall biosynthesis

Cited by 45 publications

References 19 publications

Plasmonic Enhancement of a Photocycloreversion Reaction of a Diarylethene Derivative Using Individually Dispersed Silver Nanoparticles

Plasmonic Enhancement of a Photocycloreversion Reaction of a Diarylethene Derivative Using Individually Dispersed Silver Nanoparticles

Oligonucleotide Analogues with Integrated Bases and Backbones. Part 24

Tandem mass spectra of ammonium ion, metal ion and ligated metal ion adducts of acyclic sugar derivatives

Contact Info

Product

Resources

About