N-Hydroxybenzimidazole inhibitors of ExsA MAR transcription factor in Pseudomonas aeruginosa: In vitro anti-virulence activity and metabolic stability.

ExsA is a multiple adaptational response (MAR) transcription factor, regulating the expression of a virulence determinant, the type III secretion system (T3SS) in Pseudomonas aeruginosa. Non-cytotoxic, non-antibacterial N-hydroxybenzimidazoles were identified as effective inhibitors of ExsA-DNA binding, and their potential utility as anti-virulence agents for P. aeruginosa was demonstrated in a whole cell assay. Select N-hydroxybenzimidazole inhibitors were stable in an in vitro human liver microsomal assay.

A Scalable, One-Pot Synthesis of 1,2,3,4,5-Pentacarbomethoxycyclopentadiene.

1,2,3,4,5-Pentacarbomethoxycyclopentadiene (PCCP) is a strong organic acid and a precursor to useful organocatalysts, including chiral Brønsted acids and silicon-based Lewis acids. The synthetic route to PCCP, first reported in 1942, is inconvenient for a number of reasons. The two-step synthesis requires the purification of intermediates from intractable side-products, high reaction temperatures, and extensive labor (3 days). We have developed an improved procedure that delivers PCCP efficiently in 24 hours in one pot at ambient temperature and without isolation.

Tetracyclines that promote SMN2 exon 7 splicing as therapeutics for spinal muscular atrophy.

There is at present no cure or effective therapy for spinal muscular atrophy (SMA), a neurodegenerative disease that is the leading genetic cause of infant mortality. SMA usually results from loss of the SMN1 (survival of motor neuron 1) gene, which leads to selective motor neuron degeneration. SMN2 is nearly identical to SMN1 but has a nucleotide replacement that causes exon 7 skipping, resulting in a truncated, unstable version of the SMA protein. SMN2 is present in all SMA patients, and correcting SMN2 splicing is a promising approach for SMA therapy. We identified a tetracycline-like compound, PTK-SMA1, which stimulates exon 7 splicing and increases SMN protein levels in vitro and in vivo in mice. Unlike previously identified molecules that stimulate SMN production via SMN2 promoter activation or undefined mechanisms, PTK-SMA1 is a unique therapeutic candidate in that it acts by directly stimulating splicing of exon 7. Synthetic small-molecule compounds such as PTK-SMA1 offer an alternative to antisense oligonucleotide therapies that are being developed as therapeutics for a number of disease-associated splicing defects.