Small molecule xanthine oxidase inhibitors are provided, as well as methods for their use in treating gout or hyperuricemia.

Methods described herein relate to a partial reduction of esters to aldehydes or nitrogen-containing products facilitated by Group IV transition metal catalysts, using hydrosilanes as the reductant. The method allows the product to be preserved at the aldehyde oxidation level rather than over-reduction to the corresponding alcohol and can result in the formation of value-added recycled monomers. Methods described herein can be used for the direct catalytic chemical upcycling of polyester plastic waste through depolymerization transformations.

Methods described herein relate to a partial reduction of esters to aldehydes or nitrogen-containing products facilitated by Group IV transition metal catalysts, using hydrosilanes as the reductant. The method allows the product to be preserved at the aldehyde oxidation level rather than over-reduction to the corresponding alcohol and can result in the formation of value-added recycled monomers. Methods described herein can be used for the direct catalytic chemical upcycling of polyester plastic waste through depolymerization transformations.

Described are methods for preparing a deuterated aldehyde using N-heterocyclic carbene catalysts in a solvent comprising D.sub.2O. The methods may be used to convert a wide variety of aldehydes (e.g., aryl, alkyl, or alkenyl aldehydes) to C-1 deuterated aldehydes under mild reaction conditions without functionality manipulation.

Described are methods for preparing a deuterated aldehyde using N-heterocyclic carbene catalysts in a solvent comprising D.sub.2O. The methods may be used to convert a wide variety of aldehydes (e.g., aryl, alkyl, or alkenyl aldehydes) to C-1 deuterated aldehydes under mild reaction conditions without functionality manipulation.