Diastereoselective Synthesis of the Hydroperoxide–Keto Form of (±)-Steenkrotin B

Abstract

A diastereoselective approach for the synthesis of the hydroperoxide-keto form of (±)-steenkrotin B (2') is described. The key features of the strategy involve a Diels-Alder cycloaddition, a titanium(III)-catalyzed reductive annulation, and a regio- and diastereoselective hydroperoxidation.

Late-stage modification of bioactive compounds: Improving druggability through efficient molecular editing

“…Indeed, oxygenation reactions have been extensively developed, encompassing various transformations such as C–H bond oxygenation 176 , 177 , 178 , oxygen insertion 179 , conversion of functional groups to hydroxyls 180 , 181 , 182 , 183 , 184 , 185 , hydroperoxidation 186 , 187 , 188 and oxygenation through C–C/C=C bond cleavage 189 , 190 , 191 , some of which are applied to late-stage modification of bioactive molecules.…”

Advances in the synthesis of 1,2-dioxolanes and 1,2-dioxanes

“…In a recent total synthesis work trying to access to this natural product, the last cyclizing step, namely addition of hydroperoxide function to the ketone, was unsuccessful. 72 Yet, the cyclization to the peroxyketal is supposed to be spontaneous, if favored, therefore assignment of the original structure of stenkrotin B can be questioning. Mulinic acid 73 is also a diterpenic compound isolated from Mulinum crassifolium, a shrub growing in the north of Chile.…”

Syntheses of (+)-Antrodiellin B, (−)-Hypnophilin and (−)-Coriolin and Strained 5/5/5 and 5/6/4 Skeletons via [5+2+1]/Epoxidation/Transannular Radical Cyclization

“…With this in mind, we then decided to use Ti(III)-mediated radical cyclization to test our ideas, considering that this Ti(III) mediated cyclization can build strained structures, as demonstrated by many leading synthetic chemists in their pursuits of the syntheses of natural products. [66][67][68][69][70][71][72][73][74][75][76] Our design was outlined in Fig. 3 A.…”