David G. Loughhead

The Florisil® catalyzed [1,3]-sigmatropic shift of allyl phenyl ethers — An entryway into novel mycophenolic acid analogues

Abstract Florisil ® was found to be effective in promoting the [1,3]-sigmatropic shift of mycophenolic acid related allyl phenyl ethers. Several novel mycophenolic acid analogues were thus prepared. Through a crossover experiment using two deuterated analogues of the model system, the reaction was shown to be intramolecular.

Novel hexahydropyrrolo[3,4-c]pyrrole CCR5 antagonists.

Starting with a high-throughput screening lead, a novel series of CCR5 antagonists was developed utilizing an information-based approach. Improvement of pharmacokinetic properties for the series was pursued by SAR exploration of the lead template. The synthesis, SAR and biological profiles of the series are described.

Discovery of the Irreversible Covalent FGFR Inhibitor 8-(3-(4-acryloylpiperazin-1-yl)propyl)-6-(2,6-dichloro-3,5-dimethoxyphenyl)-2-(methylamino)pyrido[2,3-d]pyrimidin-7(8H)-one (PRN1371) for the Treatment of Solid Tumors

Aberrant signaling of the FGF/FGFR pathway occurs frequently in cancers and is an oncogenic driver in many solid tumors. Clinical validation of FGFR as a therapeutic target has been demonstrated in bladder, liver, lung, breast, and gastric cancers. Our goal was to develop an irreversible covalent inhibitor of FGFR1-4 for use in oncology indications. An irreversible covalent binding mechanism imparts many desirable pharmacological benefits including high potency, selectivity, and prolonged target inhibition. Herein we report the structure-based design, medicinal chemistry optimization, and unique ADME assays of our irreversible covalent drug discovery program which culminated in the discovery of compound 34 (PRN1371), a highly selective and potent FGFR1-4 inhibitor.

Unusual reductions induced by formic acid

Abstract Treatment of xanthene carbinol 1a or xanthenylidene derivative 2a with refluxing formic acid unexpectedly gave dihydro compound 3a . Thioxanthene and acridine carbinols 1b and 1c and acridinylidene derivative 2c were also partially reduced when treated with formic acid.