Conjugates of terpenoids with 1,3,5-trisubstituted pyrazoles were synthesized by the cross-coupling of methyl 16-(2-chloro-2-oxoacetyl)labdatrienoate with terminal arylacetylenes via the Castro—Stephens reaction and heterocyclization of arylalkyne-1,2-diones with arylhydr-azines. The structure of one reaction product was established by X-ray diffraction. The conditions for the formation of furanolabdanoid arylalkyne-1,2-diones were found. The newly synthesized pyrazoles exhibit analgesic activity in a model of chemical irritation.
- Castro—Stephens cross-coupling
- phlomisoic acid
- X-ray diffraction
- ACETYLENIC KETONES
- LAMBERTIANIC ACID
- Castro-Stephens cross-coupling