Stereocontrolled Synthesis of the C1-C10 Fragments of Monensin B and Laidlomycin

An efficient synthetic route to the C1‐C10 fragments of laidlomycin and monensin B has been developed toward their total synthesis. The asymmetric carbons have been elaborated by a syn‐aldol reaction using the oxazolidinone chiral auxiliary for C6 and C7, an anti‐aldol reaction for C3 and C4, the Tishchenko–Evans reaction for C5, and a chiral building block for C2. Show me the monensin: Synthetic studies on laidlomycin (24) and monensin B (25) have been endeavored by developing an efficient synthesis of their C1–C10 fragments. The stereogenic centers have been installed by a syn‐aldol reaction using an oxazolidinone chiral auxiliary for C6 and C7, an anti‐aldol reaction for C3 and C4, the Tishchenko–Evans reaction for C5, and a chiral building block for C2.