6-methyl-8t-(2,6,6-trimethyl-cyclohex-1-enyl)-octa-3t,5c,7-trien-2-one

magnesium,ethynoxyethane,bromide

5-(2,6,6-trimethyl-cyclohex-1-enyl)-3-methyl-1-chloro-penta-2,4-diene

4-chloro-5-((2E,4E)-3-methyl-5-(2,6,6-trimethylcyclohex-1-en-1-yl)penta-2,4-dien-1-yl)-2,3-dihydrofuran

13-顺式视黄醇