An efficient and tunable route to AG7088, a rhinovirus protease inhibitor
Aldol reaction of N,N-dibenzyl valinal with propiolic acid ethyl ester derived lithium reagent provides anti-aminoalcohol 8 and syn-aminoalcohol 9, which are converted into the lactone 6 via two different routes. Alkylation of 6 followed by lactone ring o