Oxylipin total synthesis uncovers stereochemistry-dependent conformations of masked diols

A two-step anti-1,2-diol synthesis was developed using aldehyde α-oxygenation followed by Grignard addition. This method was highlighted in the synthesis and stereochemical assignment of two unnamed oxylipins from Dracontium loretense. Unexpected NMR chemical shift signatures in the differentially-masked 1,2-diols led to identification of unexpected stereochemistry-dependent conformational biases in 2,2,6,6-tetramethylpiperidinyl-masked 1,2-diols.