Publications by authors named "R D WEEKLY"

The advancement of nirmatrelvir, the active ingredient in Paxlovid, from discovery to emergency use authorization was achieved in just 17 months, requiring an unprecedented rate of chemical process development.

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Hydrothermal circulation at the axis of mid-ocean ridges affects the chemistry of the lithosphere and overlying ocean, supports chemosynthetic biological communities and is responsible for significant heat transfer from the lithosphere to the ocean. It is commonly thought that flow in these systems is oriented across the ridge axis, with recharge occurring along off-axis faults, but the structure and scale of hydrothermal systems are usually inferred from thermal and geochemical models constrained by the geophysical setting, rather than direct observations. The presence of microearthquakes may shed light on hydrothermal pathways by revealing zones of thermal cracking where cold sea water extracts heat from hot crustal rocks, as well as regions where magmatic and tectonic stresses create fractures that increase porosity and permeability.

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Two-thirds of Earth's surface is formed at mid-ocean ridges, yet sea-floor spreading events are poorly understood because they occur far beneath the ocean surface. At 9 degrees 50'N on the East Pacific Rise, ocean-bottom seismometers recently recorded the microearthquake character of a mid-ocean ridge eruption, including precursory activity. A gradual ramp-up in activity rates since seismic monitoring began at this site in October 2003 suggests that eruptions may be forecast in the fast-spreading environment.

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SAR studies on the stereoisomers of CP-470,711 suggested that in vivo epimerization was taking place in rats. Further metabolism studies revealed that no epimerization was occurring in dogs, and that no epimerization was expected in humans. A mechanism for the in vivo epimerization is proposed involving an oxidation-reduction pathway of the secondary benzylic alcohol, in contrast to an acid/base-promoted epimerization of the same center during chemical synthesis.

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Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g.

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