Fluorination and chlorination of nitroalkyl groups
摘要:
Heterocycles substituted with a nitromethyl (CH2NO2) or phenyl-nitromethyl (CHPhNO2) group were prepared by reaction of a methyl- or phenylmethyl-substituted heterocycle, respectively, with lithium di-isopropylamide followed by quenching the intermediate carbanion with methyl nitrate. Conversion of CH2NO2 attached to an alkyl or aryl moiety into a dichloronitromethyl (CCl2NO2) group was achieved using N-chlorosuccinimide and 1,8-diazabicyclo[5.4.0] undec-7-ene (DBU) in dichloromethane. Similarly, CH2NO2 attached to an alkyl or aryl group was converted into difluoronitromethyl (CF2NO2) using either 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis( tetrafluoroborate) (Selectfluor (TM)) or N-fluorobenzenesulfonimide with DBU as base and dichloromethane as solvent. Reaction of omega-nitroacetophenone with Selectfluor/DBU in dimethylformamide followed by acidification and distillation gave the parent difluoronitromethane in a useful 'one-pot' procedure. (c) 2007 Elsevier Ltd. All rights reserved.
The present invention relates, in part, to methods of treatment, prevention, and inhibition of viral disorders. In one aspect, the present invention relates to inhibition of the M2 proton channel of influenza viruses (e.g. influenza A virus) and other similar viroporins (e.g., VP24 of Ebola and Marburg viruses; and NS3 protein of Bluetongue). The present invention further relates, inter alia, to compounds which have been shown to possess antiviral activity, in particular, inhibiting the M2 proton channel of influenza viruses.