NATURAL ACETYLENES .30. POLYACETYLENES FROM LACTUCA (LETTUCE) SPECIES OF LIQULIFLORAE SUB-FAMILY OF COMPOSITAE

Seven C10 polyacetylenes were isolated from Lactuca plumieri Gren. and Godr. Dec-1-ene-4,6,8-triyn-3-one 1-hydroxydeca-4,6,8-triyn-3-one, (R)-deca-4,6,8-triyne-1,3-diol, and (R)-trans-1-(3-hydroxy-2-tetrahydrofurylidene)-hexa-2,4-diyne are new compounds and synthetic deca-4,6,8-triyn-1-ol is known. Dehydromatricarianol and its aldehyde are known natural products as also is heptadeca-8,10,16-triene-2,4,6-triyne, now isolated from the garden lettuce, L. sativa L. These are the first polyacetylenes to be found in the Liguliflorae.