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Single-pot ozonolytic synthesis of acylhydrazones based on ozonolytic cleavage of 1-methyl-2,2-dichloro-1-ethenylcyclopropane in methanol and the treatment of intermediate peroxides with a twofold excess of hydrazides of a series of carboxylic acids (decanoic, cyclohexanecarboxylic, isonicotinic, benzoic, p- and o-hydroxybenzoic ones) has been suggested.

The behavior of aliphatic (cyclohexanecarboxylic) and aromatic (salicylic and isonicotinic) carboxylic acid hydrazides toward peroxide products of ozonolysis of a terminal alkene, non-1-ene, in protic (methanol) and aprotic solvents (THF, methylene chloride) has been studied. These hydrazides are capable of acting as reducing agents or decomposing intermediate peroxides. For the synthesis of N′-octylidene isoniazid derivative, it is advisable to carry out the reaction in methanol, whereas the use of THF as solvent favors formation of N′-octylidenecyclohexane-1-carbonydrazide. Salicylic acid hydrazide showed a low efficiency; in this case, mixtures of the corresponding hydrazone with octanoic acid or its methyl ester were formed in a low yield.

Optically active cyclobutanediyl- and cyclopropanediylbisalkylidene dihydrazides of isonicotinic and salicylic acids were synthesized when the peroxide products of ozonolysis of (–)-α-pinene and (+)-Δ3-carene were reduced with isonicotinic and salicylic acid hydrazides in methanol, methylene chloride or tetrahydrofuran. Using QSAR models, high antituberculosis activity in combination with low values ​​of acute toxicity and minimal inhibitory concentration was predicted for the obtained compounds.

Treatment of peroxide ozonolysis products of the bicyclic monoterpenes (–)-α-pinene and (+)-3-carene with 4-hydroxybenzohydrazide in methylene chloride or tetrahydrofuran gave the corresponding keto acids, whereas keto esters were formed in methanol.

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.

The reaction of hydrazides of alicyclic capric and aromatic benzoic and p-hydroxybenzoic acids with the peroxide product of non-1-ene ozonolysis was studied. Capric acid hydrazide exhibits the strongest reducing properties in aprotic solvents (methylene chloride, THF) and leads to chemoselective and high-yield (~ 80%) formation of the corresponding acylhydrazone. p-Hydroxybenzoic acid hydrazide forms a similar derivative with a yield of 67% only in THF.

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.

An improved procedure for preparing 4Z-nonen-1-ol, a key intermediate in the synthesis of sex pheromones of cabbage moth and cotton bollworm, from the cyclic butadiene-isoprene dimer (1-methyl-1Z,5Z-cyclooctadiene) was developed. In this procedure, the peroxide product of regioselective partial ozonolysis (0.9 equiv of O3) of the codimer across the trisubstituted double bond is converted in one step to 9-hydroxy-5Z-nonen-2-one with NaBH(OAc)3, the reagent that does not affect the keto groups present in the structure or formed in the process.

An effective scheme for the synthesis of optically active sex pheromone of the yellow mealmoth has been developed and its preparative form has been created.