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Ozonation of quinopimaric acid methyl ester and its 2,3-dihydro derivatives involves 1,2-addition of ozone to the sterically hindered double bonds with formation of peroxy epoxides and intramolecular interaction products.

4-Aryl-8-fluoro-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolines are synthesized by acid-catalyzed (CF3CO2H) three-component cyclocondensation of 4-fluoroaniline with aromatic aldehydes and cyclopentadiene. Stable ozonides with (1R*,4S*,5aR*,6S*,11bS*)-configurations are obtained by ozonolysis of corresponding trifluoroacetyl derivatives.

Three-component condensation of lower aliphatic aldehydes (C1-C3) with arylamines and cyclopentadiene (the Povarov reaction) gave 3a,4,5,9b-tetrahydro-3H-cyclopenta[c]-quinolines. Ozonization of their N-trifluoroacetyl derivatives afforded the corresponding ozonides. Cyclocondensation of 4-fluoroaniline with formaldehyde and cyclopentadiene gave earlier unknown 2-fluoro-3b,6,6a,7,9,9a,10,12a-octahydrobenzo[i,j]dicyclopenta[b,g]quinolizine.

Ozonolysis of ω-anhydro-20-hydroxyecdysone diacetonide gave a mixture of 24- and 25-oxo derivatives, and only the first of these (23-carbaldehyde) reacted with malonic acid according to Knoevenagel to give 14α-hydroxy-2β,3β: 20,22-bis(isopropylidenedioxy)-6-oxo-27-nor-5β-cholesta-7,24-dien-26-oic acid. The oxidation of 23-carbaldehyde with ozone, followed by treatment with diazomethane, afforded 20-hydroxy-25,26,27-trinorecdysone-23-carboxylic acid methyl ester diacetonide.

Acid-catalyzed three-component condensation of methyl 12-aminodehydroabietate, aromatic aldehydes, and cyclopentadiene gave methyl (4R)-4-aryl-6-isopropyl-10,13a-dimethyl-3a,4,5,8,9,9a,10,11,12,13,13a,13d-dodecahydro-3H-cyclopenta[c]naphtho[1,2-f]quinoline-10-carboxylates and their (4S)-diastereomers. Ozonolysis of the double bond in their N-trifluoroacetyl derivatives synthesized from the (4R)-diastereomers afforded the corresponding ozonides with the (1S,4R,5aS,6R,11aR,12R,15aS,15dR)-configuration.

Selective transformations of available phytoecdysteroids to access minor ecdysteroids and some new their structural analogs are reviewed. Among them are the one-step transformation of ecdysteroids into 2-dehydro-3-epi-ecdysteroids by oxidation with ozone in pyridine, and the catalytic hydrogenation of ecdysteroids, including conjugated diene ones under basic conditions. 7,8α-Dihydro- and 7,8α-dihydro-14α-deoxyecdysteroids were synthesized by these methods. 9α,14α-Epoxyecdysteroids with the oxetane cycle in the C ring were obtained for the first time. The acid-catalyzed rearrangement of 9α,14α-epoxyecdysteroids gave 9α,13α-epoxy derivatives with the 18-methyl group migrated to the 14β-position.

Short and efficient synthesis of (3R,7R)-hexahydrofarnesyl bromide ((3R,7R)-1-bromo-3,7,11-trimethyldodecane), the terpenoid synthon for the natural α-tocopherol, has been elaborated based on the microwave-activated regioselective enolization of homochiral phytone.

A series of maleopimaric and quinopimaric acids' derivatives modified in the E-ring, at the carbonyl- and carboxyl-groups were synthesized and evaluated for their activity in vitro against respiratory viruses (influenza; rhinovirus; adenovirus; and SARS), papilloma virus, and hepatitis B and C viruses. The antiviral screening of levopimaric acid diene adducts derivatives was carried out with minimal effect on SARS and influenza type B viruses. Excellent antiviral activity of the ozonolysis product of maleopimaric acid and dihydroquinopimaric methyl-(2-methoxycarbonyl)ethylene amide was found toward papilloma virus (HPV-11 strain) with the selectivity index of SI 30 and 20, respectively. Methyl (2-methoxycarbonyl)ethylene-, 1β-hydroxy-5'-kaprolaktamo- and 4β-hydroxy-4α,14α-epoxy-13(15)-ene-dihydroquinopimaric acid derivatives have also shown activity against replication of HCV nucleic acid and low toxicity.

On the basis of ozonolysis of short-chain α-tocopherol and naphthotocopherol analogs with a terminal isopropylidene group in the side chain, a general approach to the synthesis of 6-hydroxy-2,5,7,8-tetrtamethylchroman-2-yl-and 6-hydroxy-2,5-dimethyl-3,4-dihydro-2H-naphtho[1,2-b]pyran-2-ylpropionic and-acetic acid derivatives, which are hydrophilic tocopherol analogs, was proposed.

(2RS,4′ RS,8′ RS)-Naphthotocopherol and its optically active short-chain analog were synthesized by the condensation of menadiol acetate with (3 RS,7 RS,11 RS)-isophytol and (3 RS,4 S)-3,4,8-trimethylnon-1-en-3-ol (ee ∼50%) in the presence of aluminosilicate Zeocar-10. Using (+)-camphor-10-sulfonic acid as a catalyst, naphthotocopherol analogs with the unsaturated isoprenoid side chain were obtained from (3 RS)-linalool or (3 RS,4 S)-3,4,8-trimethylnona-1,7-dien-3-ol. Ozonolysis of these compounds produced the corresponding ω-formyl derivatives.

Ozonolysis of 24,25/25,26-anhydro derivatives of 20-hydroxy-2,3:20,22-di-O-isopropylidene-ecdysone and 2,3-di-O-acetyl-20-hydroxy-20,22-O-isopropylideneecdysone, followed by trifluoromethylation of the corresponding 25-oxo derivatives afforded 2,3:20,22-di-O-isopropylidene- and 20,22-O-isopropylidene-27,27, 27-trifluoro-20-hydroxyecdysones.

Numerous records in the chemistry of pheromones, juvenile hormone analogues (juvenoids), ecdysteroids, tocopherols and related compounds demonstrate the effectiveness and, in many cases, the uniqueness of ozonolysis in the synthesis of low-molecular biologically active compounds.

The highly effective heterogeneous catalysts, the aluminosilicates Tseokar-10 and Pentasil, were found to condense hydroquinones with tertiary isoprenoid allylic alcohols. Using these catalysts d,l-α-tocopherol, (2RS,4 R,8 R)-α-tocopherol, and vitamin К1-chromanol with chiral homogeneous side chains were synthesized in high yields. The analogs of α-tocopherol – chromanols and chromenols with the terminal isopropylidene group in the side chain – were synthesized, whose selective ozonolysis resulted in the corresponding chromanes with ω-formylor ω-hydroxyl groups in the side chain.

Ozonolysis of 2,3:20,22-diacetonides of 24.25-and 25,26-anhydro-20-hydroxyecdysones afforded the corresponding ω-carbonyl derivatives. The hydrogenation of the mentioned dehydration products of 20-hydroxyecdysone acetonide yielded diacetonide of ponasterone A that provided ponasterone A and its 29,22-acetonide at hydrolysis.

The reactions of trimethylhydroquinone with isoprenoid allylic alcohols catalyzed by a Pentasil type zeolite in the H-form gave trimethyl-1,4-benzoquinones with the corresponding isoprenoid group, which were subsequently transformed into the target Δ3-chromenes on treatment with pyridine. Partial ozonolysis of chromenes proceeded selectively at the Δ-bond of the side chain, resulting in the corresponding chromenes with an ω-carbonyl group.

α-Tocopherol analogs with double bond-containing side chains were synthesized by condensation of trimethylhydroquinone with optically active (3R/S,4S)-3,4,8-trimethylnona-1,7-dien-3-ol and linalool in the presence of the zeolite-containing Tseokar-10 aluminosilicate. Ozonolysis of these compounds gave the corresponding chromans with ω-formyl or (after hydride reduction) ω-hydroxyl groups in the side chain.

Ozonization of perfluoro-1-octene in Freon-113 yields the corresponding ozonide whose catalytic hydrogenation over Pd/C or hydride reduction leads to formation of perfluoroheptanoic acid; the reduction with lithium aluminum hydride gives 2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoro-1-heptanol. Ozonization of perfluoro-1-octene in Freon-113 containing excess (≥3 equiv) alcohol affords the corresponding perfluoroheptanoic acid ester.

Syntheses carried out with participation of the author of terpenoids, polyprenols, prenylcarboxylic acids, insect pheromones, and juvenoids based on α,ω-dicarbonyl 1,5-unsaturated isoprenoid compounds with (Z)- and (E)-configurations, obtained by controlled ozonolysis of isoprene cyclic oligomers and polyisoprene rubbers, are considered.

The ozonolysis of isoabienol in MeOH followed by hydrogenation of the peroxide ozonolysis products on Lindlar catalyst afforded ambreinolide that under treatment with diisobutylaluminum hydride furnished 8α,13-epoxy-14,15,16-trisnorlabd-12-ene.

Syntheses carried out with participation of the author of terpenoids, polyprenols, prenylcarboxylic acids, insect pheromones, and juvenoids based on α,ω-dicarbonyl 1,5-unsaturated isoprenoid compounds with (Z)- and (E)-configurations, obtained by controlled ozonolysis of isoprene cyclic oligomers and polyisoprene rubbers, are considered.

A new route, based on the partial ozonolysis of ω-acetyl derivatives of alk-1-en-4-ynes, is proposed for the synthesis of 11RS-hydroxydodec-3Z-enoic acid, the cyclization of which gives dodec-3Z-en-11RS-olide (ferrulactone II) — a racemic analogue of one of the macrolide components of the aggregation pheromone of the rust-red grain beetle.

A new approach to the synthesis of 11RS-hydroxy- and 12-hydroxydodec-3Z-enoic acids has been developed with the use, in one of the key stages, of the partial ozonolysis of the acetates of the corresponding methylene-separated enynic alcohols.

A minor ecdysteroid from Froelichia floridana, namely, 2-dehydro-3-epi-20-hydroxyecdysone has been obtained by the one stage ozonization of 20-hydroxyecdysone in pyridine.