[(2R,6S)-6-(2-oxoethyl)tetrahydropyran-2-yl]acetic acid ethyl ester

((2R,6S)-6-allyltetrahydropyran-2-yl)acetic acid ethyl ester

(S)-1-[(2S,6R)-6-(2-hydroxyethyl)tetrahydropyran-2-yl]pent-4-en-2-ol

[(2R,6S)-6-((S)-2-hydroxypent-4-enyl)tetrahydropyran-2-yl]acetic acid ethyl ester

(2R,6S)-2-[2-(tert-butyldimethylsilanyloxy)ethyl]-6-[(S)-2-(tert-butyldimethylsilanyloxy)pent-4-enyl]tetrahydropyran