Lewis acid-promoted 5/6-exo trig hydroalkoxylation/reduction cascade of ω-hydroxy cyclopropenes gave expeditious, stereoselective access to THF/THP derivatives.
Spirodioxolanes were identified as a new series of direct-acting nsP2 helicase inhibitors with activity against alphaviruses. Analogs such as 6b maintained activity against viral mutants with resistance to first-generation nsP2 helicase inhibitors.
Artemeriopolides A–D (1–4), four novel cadinane sesquiterpenoid dimers featuring the rare 2-oxaspiro[4.6]undecan-1,7-dione, 2-oxaspiro[4.5]decan-1-one, and 2-oxaspiro[5.5]undecan-1-one ring systems, were isolated from Artemisia eriopoda.
Developments in the synthesis and application of strained spiro heterocycles are discussed, given their potential as non-classical rigid three-dimensional bioisosteres in drug development.
Seven new and immunosuppressive dimeric diterpenoids were elucidated. Compound 1 possesses a new carbon skeleton. The biomimetic transformation of 2 into 1 was achieved under mild, as well as peroxide- and metal-free conditions.