Synthesis and biological evaluation of natural methyl ester, lactone and their synthetic analogs.

(2)- methyl ester and (4)- lactone were recently identified as major components in essential oils and extracts of from Togo. Extended biological evaluation of these acetylenic compounds was however hampered by the reduced amounts isolated. A synthetic route was designed providing access to larger quantities of these two natural products as well as to original non-natural analogs with the prospect of exploring for the first time the structure-activity relationships in this series.