(2S,3R)-3-[1-((2S,3S)-3-Allyl-1,4-dioxa-spiro[4.4]non-2-yl)-vinyl]-1,4-dioxa-spiro[4.4]nonane-2-carbaldehyde

(2S,3S)-2-allyl-3-(1-((2R,3R)-3-ethynyl-1,4-dioxaspiro[4.4]nonan-2-yl)vinyl)-1,4-dioxaspiro[4.4]nonane

{(2R,3R)-3-[1-((2S,3S)-3-Allyl-1,4-dioxa-spiro[4.4]non-2-yl)-vinyl]-1,4-dioxa-spiro[4.4]non-2-yl}-methanol

((2S,3S)-3-{1-[(2R,3R)-3-(4-Methoxy-benzyloxymethyl)-1,4-dioxa-spiro[4.4]non-2-yl]-vinyl}-1,4-dioxa-spiro[4.4]non-2-yl)-acetaldehyde

(2R,3R)-2-(1-((2S,3S)-3-allyl-1,4-dioxaspiro[4.4]nonan-2-yl)vinyl)-3-(((4-methoxybenzyl)oxy)methyl)-1,4-dioxaspiro[4.4]nonane