15008-33-0Relevant articles and documents
Hydrophobic Vitamin B12. Part 6. Carbon-skeleton Rearrangement via Formation of Host-Guest Complexes derived from an 'Octopus Azaparacyclophane and hydrophobic Vitamin B12 Derivatives: a Novel Holoenzyme Model System
Murakami, Yukito,Hisaeda, Yoshio,Kikuchi, Jun-ichi,Ohno, Teruhisa,Suzuki, Masashi,et al.
, p. 1237 - 1246 (1988)
The alkylation reactions of a hydrophobic vitamin B12 derivative with alkyl bromides in an 'octopus' azaparacyclophane having eight hydrocarbon chains have been investigated.Molecular discrimination has been shown to originate from electrostatic interaction between the octopus cyclophane and the alkyl bromides.Alkylation was enhanced by desolvation and proximity effects operating on the reacting species via formation of a ternary complex composed of the octopus cyclophane, the hydrophobic vitamin B12 derivative, and an alkyl halide.Carbon-skeleton rearrangement reactions of alkyl ligands bound to the hydrophobic vitamin B12 were found to be markedly favoured in the hydrophobic cavity provided by the octopus cyclophane, relative to the reactions in methanol and benzene, under anaerobic photolysis conditions at ordinary temperatures.The same reactions took place readily in solid benzene below 4 deg C under similar conditions.The central cobalt atom of the hydrophobic vitamin B12 participates in the rearrangement reaction via formation of a tight pair with an alkyl radical species.Non-enzymic rearrangement reactions have been shown here to proceed quite efficiently by employing a relevant apoenzyme model.
Ion channel topography of the neuronal nicotinic acetylcholine receptor: Pharmacochemical approaches
Gmiro,Brovtsyna,Serdyuk,Lukomskaya
, p. 116 - 127 (2002)
Forty-three bisammonium ganglionic blockers were synthesized to study the structure of the ion channel of nicotinic acetylcholine receptor. The conformational parameters of these blockers were studied, and their effects toward the ganglionic transmission in situ on the sympathetic feline superior cervical ganglia and in vitro on the parasympathetic guinea-pig small intestine ganglia were determined. A model of the binding site for the bisammonium ganglionic blockers in the neuronal ion channel was proposed.
Thiol- And Disulfide-Containing Vancomycin Derivatives against Bacterial Resistance and Biofilm Formation
Gademann, Karl,Shchelik, Inga S.
supporting information, p. 1898 - 1904 (2021/11/16)
Antibiotic-resistant and biofilm-associated infections constitute a rapidly growing issue. Use of the last-resort antibiotic vancomycin is under threat due to the increasing appearance of vancomycin-resistant bacteria as well as the formation of biofilms. Herein, we report a series of novel vancomycin derivatives carrying thiol- and disulfide-containing moieties. The new compounds exhibited enhanced antibacterial activity against a broad range of bacterial strains, including vancomycin-resistant microbes and Gram-negative bacteria. Moreover, all obtained derivatives demonstrated improved antibiofilm formation activity against VanB-resistant Enterococcus compared to vancomycin. This work establishes a promising strategy for combating drug-resistant bacterial infections or disrupting biofilm formation and advances the knowledge on the structural optimization of antibiotics with sulfur-containing modifications.
Organic synthesis in soft wall-free microreactors: Real-time monitoring of fluorogenic reactions
Marchand,Dubois,Delattre,Vinet,Blanchard-Desce,Vaultier
, p. 6051 - 6055 (2008/12/22)
A new approach of "laboratory on a chip" (LOC) devoted to organic synthesis based on electrically operated ionic liquid microdroplets used as air-stable "soft" microreactors was recently introduced. A number of challenging issues have yet to be addressed