Water-compatible Cycloadditions of Oligonucleotide-conjugated Strained Allenes for DNA-encoded Library Synthesis.

DNA-encoded libraries of small molecules are being explored extensively for the identification of binders in early drug-discovery efforts. Combinatorial syntheses of such libraries require water- and DNA-compatible reactions, and the paucity of these reactions currently limit the chemical features of re-sulting barcoded products. The present work introduces strain-promoted cycloadditions of cyclic allenes under mild condi-tions to DNA-encoded library synthesis. Owing to distinct cycloaddition modes of these reactive intermediates with acti-vated olefins, 1,3-dipoles and dienes, the process generates diverse molecular architectures from a single precursor. The resulting DNA-barcoded compounds exhibit unprecedented ring and topographic features-related to elements found to be powerful in phenotypic screening.