Catalyst-controlled switchable [4 + 1], [4 + 3] and [3 + 2] domino reactions of azadienes and MBH carbonates: diverse synthesis of benzothiophene fused derivatives.

Catalyst-controlled switchable domino reactions between azadienes bearing a benzothiophene moiety and isatin-derived MBH carbonates were developed. The [4 + 1] annulation was triggered in the presence of DABCO, giving a variety of benzothiophene fused pyrrole derivatives, while the [4 + 3] annulation occurred when changing the catalyst to DMAP. Furthermore, the [3 + 2] annulation mode was observed with the use of catalytic PhPMe.

Repercussions of COVID-19 pandemic on solid waste generation and management strategies.

It has been over ten months since the beginning of the 2019 coronavirus disease (COVID-2019), and its impact on solid waste management, especially medical waste, is becoming clearer. This study systematically reviews the potential influences of the COVID-19 pandemic on medical waste, personal protection equipment waste and municipal solid waste (MSW), and discusses the corresponding measures and policies of solid waste management in typical countries. The results show that the generation of medical waste from the pandemic increased significantly, with 18%-425% growth.

Darzens reaction of thioisatins and sulfonium salts: approach to the synthesis of thiochromenone derivatives with anticancer potency.

A new Darzens reaction of thioisatins and sulfonium salts has, for the first time, been reported. This reaction allows efficient access to thiochromenone derivatives in good to excellent yields under mild reaction conditions. The substrate scope includes both electron-withdrawing and electron-donating groups on both the thioisatins and sulfonium salts.