Solvent and catalyst free route to 3-indolyl glycoconjugates: synthesis of sugar tethered isoxazolines and isoxazoles from 3-indolyl nitroalkanes†
Abstract
An expedient, solvent and catalyst free strategy for the synthesis of sugar based bis(indolyl)methanes and indolyl nitroalkanes has been developed. The protocol works well within a wide range of substrates, and tolerates various N/O protecting groups. The sugar tethered nitroalkanes were converted to the corresponding nitrile oxides, and subsequently transformed to novel isoxazolines and isoxazoles by cycloaddition with appropriate dipolarophiles.