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A convenient synthesis of drimenol by treatment of readily available drimane-8α, 11-diol 11-monoacetate with sulfuric acid in ethanol under mild conditions was developed. Oxidation of drimenol with selenium dioxide gives known drim-7-ene-9α, 11-diol and drim-7-ene-11,12-diol as the major products.

An efficient one-step synthesis of the diacetate of the tetracyclic triterpenoid onoceranediol (4) by radical cleavage of the readily available 12-hydroperoxy-8α,12-epoxy-11-bishomodrimane is described. Drim-9(11)-en-8α-yl acetate (7) is formed in this reaction as a byproduct. Onoceranediol diacetate 4 is converted into onoceranediol on treatment with LiAlH4, and acetate 7 is transformed into drim-9(11)-en-8α-ol on saponification.

Reaction of 4-(2-, 3-, 4-pyridyl, or 2-quinolyl)but-3-en-2-ones with carbethoxymethylenetriphenylphosphorane and subsequent hydrolysis gives 3-methyl-5-(2-, 3-, 4-pyridyl, or 2-quinolyl)-2,4-pentadienoic acids and also 3-methyl-4-(2-, 4-pyridyl-, or 2-quinolylmethyl)but-2-en-4-olides as products of cyclization of the corresponding pentadienoic acids.

A simple, efficient two-step synthesis of a mixture of diethyl (Z) and (E)-3-methylglutaconates from ethyl 4,6-dimethyl-2-oxo pyran-5-carboxylate in 83% yield is described. On the basis of this synthesis an improved procedure for the preparation of a mixture of (Z)- and (E)-3-methylglutaconic acids from ethyl acetoacetate in 44% overall yield was elaborated