Volume 54, Nº 11 (2018)

The review covers the literature on the total synthesis of cross-conjugated cyclopentenone prostaglandins (PGs), published from 2000 until present. In view of the specific features differentiating cyclopentenone PGs from prostaglandins of other types, special attention in the review is focused on the biochemistry and physiological functions of the most important representatives of cyclopentenone PGs. Data on analogs of cyclopentenone PGs are presented, and certain aspects of structure–activity correlations and potential practical applications of these compounds are discussed.

Reaction of S,S′-dimethyl-N-nitroimidodithiocarbonate with alkali in aqueous-alcoholic solution results in salts of S-methyl-N-nitrothiocarbamate. In anhydrous ethanol a salt of nitrouretane is obtained. By the reaction of S-methyl-N-nitrothiocarbamate salts with hydrazine 4-nitrosemicarbazide salts were prepared.

N-Alkyl- and N,N-dialkyl-substituted anilines were obtained in the reaction of aniline and its derivatives with primary and secondary alcohols in the presence of catalysts CuCl₂·2H₂O, CuBr₂ and halomethanes as promoters.

Possible application of methyl 2-(bromomethyl)acrylate, methyl acrylate, and glycine in the synthesis of functionalized pyrrolidones was considered.

Reaction of 4-tert-butylphthalimide with zinc acetate at 260°С results in the formation of a mixture of tetrakis(4-tert-butylbenzo)porphyirin as well as acyclic four-, three-, and two-unit condensation products.

Nitration of 6-substituted 2-chloro-6,7-dihydro-5H-pyrrolo[1,2-a]imidazoles was used to synthesize the corresponding 3-nitro derivatives. 6-Substituted 6,7-dihydro-5H-pyrrolo[1,2-a]imidazoles are highly selectively nitrated to the 2-position. 6-Substituted 2-amino-3-nitro-, 3-amino-2-nitro-, and 2-azido-3-nitro-6,7-dihydro- 5H-pyrrolo[1,2-a]imidazoles were synthesized. 2-Nitro-6,7-dihydro-5H-pyrrolo[1,2-a]imidazole was nitrated with a mixture of sulfuric and nitric acids to obtain 2,3-dinitro-6,7-dihydro-5H-pyrrolo[1,2-a]imidazole.

O and N centers of 3-trifluoromethyl-1,2-dihydroquinoxalin-2-one anion shows in reactions with haloalkanes an ambident nucleophilic character. The chemoselectivity of the reaction depends on the alkylating agent: the methylation of 3-trifluoromethyl-1,2-dihydroquinoxalin-2-one in acetonitrile in the presence of K₂CO₃ yields only an N-methyl isomer whereas under the same conditions in the reaction with (4-bromobutyl)-acetate О- and N-alkylations are competing.

Nonracemic 3-substituted 4-(1H-tetrazol-1-yl)butanoic acids, analogs of the neurotropic drugs phenibut, tolibut, and baclofen, were synthesized by a three-component reaction of the R-isomers of the corresponding amino acids, triethyl orthoformate, and sodium azide. The key stage of the synthesis is the asymmetric addition of diethyl malonate to nitroalkenes, catalyzed by a Ni(II) complex of (S,S)-N,N′-dibenzylcyclohexane-1,2-diamine.

Bis(2-bromo-3-hydroxypropyl) selenide was synthesized in quantitative yield by the reaction od selenium bromide with allyl alcohol. The product undergoes facile methanolysis at room temperature, which is accompanied by a rearrangement and involves substitution of bromine and hydroxy groups, located β to the selenium atom, to form bis(1,3-dimethoxypropan-2-yl) selenide and (3-hydroxy-2-methoxypropyl)(1,3-dimethoxypropan-2-yl) selenide.

1-, 2-Methoxy-, 1,3-dimethoxyadamantane, and 1-, 4-methoxydiadamantane were prepared by the reaction of adamantyl and diadamantyl halides with dimethyl carbonate in the presence of zeolite catalysts NiHY or FeHY free of binders. Optimum ratio of catalysts and reagents were found and the reaction conditions for the selective synthesis of methoxyadamantanoids were developed.

1,6-Diarylhexane-1,3,4,6-tetraones react with o-aminothiophenol forming 3-aryl-1-(1,3-benzothiazol-2-yl)-3-hydroxyprop-2-en-1-ones.

According to DFT/M06-2X/6-311G(d,p) calculations, the binding energy of the lithium cation with benzene and polycyclic aromatic hydrocarbons of the general formula C_6n²H_6n (n = 2–5) increases in the order C₆H₆ < C₂₄H₁₂ < C₅₄H₁₈ < C₉₆H₂₄ < C₁₅₀H₃₀ and tends for saturation. The Li⁺···C_6n²H_6n bonds are characterized by a considerable dynamic instability and predominant π contribution.