Library Synthesis: Building Block Selection, Handling, and Tracking.

Careful selection and manipulation of small molecule building blocks is crucial to the success of a DNA-encoded library. Building block selection impacts the quality of the hits arising out of a selection assay, while proper sample handling and tracking ensure follow-up synthetic work is done with the appropriate synthetic map in mind. In this chapter, possible strategies for building block selection are outlined, as well as best practices for handling and tracking samples to be used for validation and library synthesis.

Small-molecule studies identify CDK8 as a regulator of IL-10 in myeloid cells.

Enhancing production of the anti-inflammatory cytokine interleukin-10 (IL-10) is a promising strategy to suppress pathogenic inflammation. To identify new mechanisms regulating IL-10 production, we conducted a phenotypic screen for small molecules that enhance IL-10 secretion from activated dendritic cells. Mechanism-of-action studies using a prioritized hit from the screen, BRD6989, identified the Mediator-associated kinase CDK8, and its paralog CDK19, as negative regulators of IL-10 production during innate immune activation. The ability of BRD6989 to upregulate IL-10 is recapitulated by multiple, structurally differentiated CDK8 and CDK19 inhibitors and requires an intact cyclin C-CDK8 complex. Using a highly parallel pathway reporter assay, we identified a role for enhanced AP-1 activity in IL-10 potentiation following CDK8 and CDK19 inhibition, an effect associated with reduced phosphorylation of a negative regulatory site on c-Jun. These findings identify a function for CDK8 and CDK19 in regulating innate immune activation and suggest that these kinases may warrant consideration as therapeutic targets for inflammatory disorders.

Synthesis and evaluation of antimigratory and antiproliferative activities of lipid-linked [13]-macro-dilactones.

The biological activities of a family of novel, lipid-linked 13-membered-ring macro-dilactones are reported. These [13]-macro-dilactones were synthesized by diacylation of functionalized diols, followed by ring-closing metathesis under conditions we had previously reported. Antimigratory, cytostatic and cytotoxic activities of the compounds against cancer cells were evaluated. Compound 13 was the most potent in the series, while compound 10 had the broadest concentration range of subtoxic antiproliferative activity. These compounds share common structural components, namely the [13]-macro-dilactone templated by an octyl alpha-glucoside 4,6-diol.