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Efficient syntheses of six potentially useful optically pure macroheterocycles with ester and dihydrazide fragments were developed from available natural Δ3-carene through intermediate (31R,33S)-32,32-dimethyl-3(1,3)cyclopropyla-5-oxohexanoic acid using in the key steps [2+1]-reactions of the last with di- or triethylene glycol and [1+1]-condensation of the resulting α,ω-diketodiesters with several dicarboxylic acid dihydrazides. The structures of the obtained compounds were confirmed by IR and NMR spectroscopy and LC-MS.

Reduction of the peroxide ozonolysis products of (–)-α-pinene and (+)-3-carene by capric and benzoic acid hydrazides in CH2Cl2 or THF produced diacylhydrazones either pure or mixed with the corresponding ketoacids. The capric acid diacylhydrazone formed primarily in CH2Cl2; benzoic acid diacylhydrazone, in THF. The only reaction products formed in MeOH were the corresponding ketoesters.

Controlled ozonolysis of (S)-(–)-limonene in the presence of Py gave 4-methyl-3-(3-oxobutyl)pent-4-enal or 4-methyl-3-(3-oxobutyl)pent-4-enoic acid depending on the solvent (CH2Cl2 or MeOH). Exhaustive ozonolysis produced 3-acetyl-6-oxoheptanoic acid. Ozonolysis of abietic acid in CH2Cl2 in the presence of Py formed stable epoxytrioxolaneabietic acid; in MeOH–Py, the epoxyketoaldehyde corresponding to cleavage of the C13–C14 bond.