No abstract

Influenza A virus is the major cause of seasonal or pandemic flu worldwide. Two main treatment strategies–vaccination and small molecule anti-influenza drugs are currently available. As an effective vaccine usually takes at least 6 months to develop, anti-influenza small molecule drugs are more effective for the first line of protection against the virus during an epidemic outbreak, especially in the early stage. Two major classes of anti-influenza drugs currently available are admantane-based M2 protein blockers (amantadine and rimantadine) and neuraminidase (NA) inhibitors (oseltamivir, zanamivir, and peramivir). However, the continuous evolvement of influenza A virus and the rapid emergence of resistance to current drugs, particularly to amantadine, rimantadine, and oseltamivir, have raised an urgent need for developing new anti-influenza drugs against resistant forms of influenza A virus. In this review, we first give a brief introduction of the molecular mechanisms behind resistance, and then discuss new strategies in small-molecule drug development to overcome influenza A virus resistance targeting mutant M2 proteins and neuraminidases, and other viral proteins not associated with current drugs.

Post-stroke angiogenesis facilitates neurovascular remodeling process and promotes neurological recovery. Proangiogenic effects of Salvianolic acids (Sals) have been reported in various ischemic disorders. However, the underlying mechanisms are still poorly understood. Previous studies of our laboratory have demonstrated that activating Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway is involved in the protection against cerebral ischemia/reperfusion injury. In this study, we investigated the impacts of Sals on angiogenesis and long-term neurological recovery after ischemic stroke as well as the potential mechanisms. Male mice subjected to permanent distal middle cerebral artery occlusion were administrated with Sals, 5-bromo-2'-deoxyuridine, and JAK2 inhibitor AG490 once daily from day 1 to day 14 after distal middle cerebral artery occlusion. Compared with the control group, Sals treatment significantly improved neurological recovery at day 14 and 28 after ischemic stroke. Sals enhanced post-stroke angiogenesis, pericytes and astrocytic endfeet covered ratio in the peri-infarct area. The JAK2/STAT3 signaling pathway was activated by Sals in the angiogenesis process, and inhibition of JAK2/STAT3 signaling blocked the effects of Sals on post-stroke angiogenesis and neurological recovery as well as abolished the mediation of proangiogenic factors. In summary, these data suggest that Sals administration enhances cerebral angiogenesis and promotes neurological recovery after ischemic stroke, mediated by the activation of JAK2/STAT3 signaling pathway.

The 3C-like protease (3CLpro) is an essential enzyme for the replication of SARS-CoV-2 and other coronaviruses and thus is a target for coronavirus drug discovery. Nearly all inhibitors of coronavirus 3CLpro reported so far are covalent inhibitors. Here, we report the development of specific, noncovalent inhibitors of 3CLpro. The most potent one, WU-04, effectively blocks SARS-CoV-2 replications in human cells with EC50 values in the 10-nM range. WU-04 also inhibits the 3CLpro of SARS-CoV and MERS-CoV with high potency, indicating that it is a pan-inhibitor of coronavirus 3CLpro. WU-04 showed anti-SARS-CoV-2 activity similar to that of PF-07321332 (Nirmatrelvir) in K18-hACE2 mice when the same dose was administered orally. Thus, WU-04 is a promising drug candidate for coronavirus treatment.

A conceptually novel sulfoxonium metathesis reaction between TMSOI and cost-effective DMSO-d 6 is developed for the efficient generation of a new trideuteromethylation reagent TDMSOI. The new reagent TDMSOI is produced highly efficiently by simply heating a mixture of TMSOI and DMSO-d 6 and directly used for subsequent trideuteromethylation in a “one-pot” operation. The preparative power of the new versatile reagent and the “one-pot” protocol is demonstrated by its use to install the −CD3 moiety into broad functionalities including phenols, thiophenols, acidic amines, and enolizable methylene units in high yield and at a useful level of deuteration (>87% D).