Abstract The enantiospecific synthesis of 3-acetoxy-trans-β-lactams via the Staudinger [2+2] cycloaddition reaction of polyaromatic imines with bicyclic (+)-car-3-ene was investigated. The sterically hindered polyaromatic substituent at the N1 position in the imines plays a significant role, directing the cycloaddition reaction to stereoselective formation of trans-(3R,4R)-N-azetidin-2-ones. The results

Abstract Potassium salts of arylmethylidene derivatives of malononitrile trimer were obtained by the reactions of aromatic aldehydes with malononitrile trimer in an aqueous medium under micellar catalysis. The optical properties of the synthesized salts were studied to show they absorb in the range of 313–436 nm, depending on the substituent. Exchange reactions with various metal salts showed that

Abstract The reaction of 5-(arylmethylidene)-2,4,6-pyrimidine-2,4,6(1H,3H,5H)-triones with morpholine in the presence of hydrogen peroxide and catalytic amounts of sodium tungstate leads to the synthesis of 2-aryltetrahydro-1'H,2H-spiro(isoxazole[3,2-c][1,4]oxazine-3,5'-pyrimidine)-2',4',6'(3'H)-triones.

Abstract Phenylethynyl sulfones of the general formula RSO2C≡CPh (R = p-Tol, Ph, CH3) undergo a photochemically induced anti-stereoselective addition to the central C1–C7 bond of 1-bromotricyclo[4.1.0.02,7]heptane to form monoadducts of the bicyclo[3.1.1]heptane (norpinic) series containing a syn-sulfonyl group in position 7 and a phenylethynyl moiety on C6. Treatment of the synthesized adducts with

Abstract Xanthylium, thioxanthylium, or tropylium salts were reacted with imidazole and benzimidazole. The reactions gave the substitution products of the secondary amino hydrogen atoms in the imidazole and benzimidazole heterorings by xanthyl, thioxanthyl, and tropylium fragments. The structure of the obtained compounds was established by mass spectrometry, 1H NMR spectroscopy, and X-ray diffraction

Abstract Hydroxyl-containing esters of bis(O-butyl xanthic acid) have been synthesized. The presence of the xanthate and hydroxyl groups at neighboring carbon atoms results in that upon thermal exposure the synthesized compounds undergo intramolecular cyclization to form a heterocyclic compound. The structures of the obtained O-butyl xanthic acid derivatives were established by IR and 1H and 13C spectroscopy

Abstract Novel 3-amino-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2,7-naphthyridines were synthesized on the basis of monohydrazides derived from 2,7-naphthyridines. The cyclization of 3-chloro-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2,7-naphthyridine with hydrazine hydrate gave the tricyclic pyrazolo[3,4-c]-2,7-naphthyridine, which was used to prepare the novel heterocyclic system pyrimido[1',2':1,5]pyrazolo[3,4-c]-2

Abstract A method has been developed for the preparation of a new type of dispiro derivative, 5''-bromo-2-[(4-chlorophenyl)sulfanyl]-1'-methyl-1,4'-diphenyldispiro[imidazole-4,3'-pyrrolidine-2',3''-indoline]-2'',5(1H)-dione, starting from 2-thiohydantoin and using a 1,3-dipolar cycloaddition reaction. The configuration of the target dispiro derivative was unambiguously established by physicochemical

Abstract 8-Aroyl-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazin-1,6,7-triones react with 2-aminobenzenethiol to give 3'-aroyl-4'-hydroxy-1'-(2-hydroxyethyl)spiro[benzo[b][1,4]thiazine-2,2'-pyrrole]-3,5'(1'H,4H)-diones.

Abstract Chlorination of an S-methyl-5-cyano-6-arylthiouracil derivative afforded a chloropyrimidine which underwent aminolysis followed by cyclization to give pyrimidothiazolpyrimidine and imidazopyrimidines. The same thiouracil derivative was also used to prepare oxadiazolopyrimidines, triazolopyrimidines, and pyrimidotriazepines via a diaminopyrimidine and its cyclization with a variety of reagents

Abstract A novel 3-chloro-3-(4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl)prop-2-enal was synthesized from 6-acetyl-4,9-dimethoxy-5H-furo[3,2-g]chromen-5-one by the Vilsmeier–Haack reaction, and its chemical reactivity toward some mono- and di-nitrogen nucleophiles was investigated. The reactions of the synthesized enal with primary amines, specifically benzylamine and p-toluidine, gave novel enamines

Abstract Carboxamides and carbamoyl oximes containing both adamantyl and 3,6-diazahomoadamantyl fragments were synthesized. The reactions proceed in mild conditions and in high yields. The synthesized compounds are promising as soluble epoxide hydrolase inhibitors.

Abstract A series of 1,3-disubstituted ureas with a phenyl fragment containing fluorine and/or chlorine substituents in different positions were synthesized with yields of 33–80%. 1-Isocyanatoadamantane was prepared for the first time by the reaction of diphenylphosphoryl azide with (adamantan-1-yl)carboxylic acid in a yield of 85%.

Abstract The reactions of 4-[(4-formylphenoxy)methyl] derivatives of ethyl 6-alkyl(phenyl)-substituted nicotinates with primary amines, glycols and 1,2-phenylenediamine, leading to the formation of the corresponding azomethines, 1,3-dioxolanes, and 2,3-dihydrobenzylimidazoles with preparative yields were studied. The synthesized azomethines were selectively reduced into the corresponding secondary

Abstract Novel 1,3-cyclopentathiazine and pyrimidothiazine derivatives were synthesized starting from 7-benzyl-4-phenylcyclopenta[d][1,3]thiazin-2-amine (CTA) prepared by a one-pot multicomponent reaction of cyclopentanone, benzaldehyde, and thiourea. Cyclocondensation of CTA with benzylidenemalononitrile gave a pyrimidothiazine. Oxidation of cyclopentathiazine with hydrogen peroxide afforded the corresponding

Abstract The reaction of phthalimide with zinc acetate gave a previously unknown three-unit condensation product 3-[(E,Z)-{(E,Z)-3-[(1-hydroxy-1-methyl-1H-isoindol-3-yl)methylene]isoindolin-1-ylidene}methyl]-1H-isoindol-1-one. Heating the latter with 2-methylquinoline and zinc oxide followed by treatment with sulfuric acid resulted in the synthesis of 5-(quinoline-2-yl)tetrabenzoporphyrin, which was

Abstract The fragmentation of previously inaccessible alkyl [(5-amino-1H-pyrrol-2-yl)sulfanyl]acetates under electron (70 eV) and chemical (reactant gas methane) ionization conditions was studied for the first time. Under electron ionization, all the studied compounds form a molecular ion (Irel 7–100%), the main primary fragmentation pathway of which is associated with the C–S bond cleavage in the

Abstract The reactions of diaryl-, aryl-, and alkyl–arylcyclopropanes with ethyl nitrite in the presence of sulfur trioxide and sulfur trioxide dioxane complex, as well as the reactions of 1-alkyl-2-arylcyclopropanes with NOBF4 were studied. It was found that the attack of the nitrosonium cation, accompanied by the formation of a benzyl carbocation, leads to the formation of isoxazolines. The introduction

Abstract An efficient method has been developed for the synthesis of N-aryl(alkyl)-N-(hexaoxazadispiroalkanyl)amines by the reaction of 3,6-di(spiroalkanyl)-substituted heptaoxacycloundecanes with hydrazine derivatives (3-chlorophenylhydrazine, phenylhydrazine, 2,4-dinitrophenylhydrazine, and tert-butylhydrazine) with Sm-containing catalysts. It was found that amines with macrocyclic spiro-linked azatriperoxide

Abstract Diterpene derivatives of imidazole and benzimidazole were synthesized by the phase-transfer alkylation of imidazole and benzimidazole with a sterically congested diterpene bromoketone. The corresponding imidazolium and benimidazolium salts were also prepared.

Abstract Transesterification of commercial titanium(IV) alkoxides with 2,2,3,3-tetrafluoropropan-1-ol, followed by in situ transesterification of mixed titanium(IV) alkoxides thus formed with diphenyl carbonate, afforded alkyl 2,2,3,3-tetrafluoropropyl carbonates and bis(2,2,3,3-tetrafluoropropyl) carbonate in up to 60% yield. The degree of transesterification decreased in the series (i-PrO)4Ti > (EtO)4Ti

Abstract The reaction of 5,7-dinitroquinolin-8-ol with hydrazine hydrate afforded 5-aminopyrido[2,3-d]pyridazin-8(7H)-one in 50% yield instead of expected product of reduction of the 7-nitro group, 7-amino-5-nitroquinolin-8-ol.

Abstract Ring opening of 3-[(diarylmethylidene)hydrazinylidene]-5-tert-butylfuran-2(3H)-ones by the action of alcohols afforded previously unknown alkyl 2-[2-(diarylmethylidene)hydrazinyl]-5,5-dimethyl-4-oxohex-2-enoates which were found to exist in solution as mixtures of tautomers.

Abstract The reaction of dicobalt octacarbonyl with 8,12,13,14-tetradehydro-11-deoxymisoprostol analog and its trimethylsilyl ether afforded the corresponding dicobalt hexacarbonyl complexes. Spectral characteristics of the complexes and their cytotoxicity in comparison to the free ligands are discussed.

Abstract Bioactive pyranonaphthoquinone analogs, (1R,3S)-deoxythysanone, (1R,3S)-thysanone, and (1R,3S)-demethoxythysanone can be efficiently synthesized from a common intermediate product, (S)-3-methyl-3,4-dihydro-1H-isochromene-5,8-dione. We have developed a short synthetic route to pyranonaphthoquinone antibiotics, which involves enantioselective reduction of homobenzylic ketone in the presence

Abstract 8-Aroyl-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-1,6,7-triones reacted with urea to give 9-aroyl-8-hydroxy-6-(2-hydroxyethyl)-1,3,6-triazaspiro[4.4]non-8-ene-2,4,7-triones.

Abstract 3-Amino-5-phenyl-1,3-thiazolidin-2-iminium bromide was synthesized for the first time by reaction of (1,2-dibromoethyl)benzene with thiosemicarbazide hydrochloride. Its condensation with aromatic aldehydes afforded the corresponding Schiff bases. The structure of the isolated compounds was confirmed by 1H and 13C NMR spectroscopy.

Abstract The reaction of chloromethyl propargyl ether with 4-(bromomethyl)benzaldehyde in the presence of zinc metal and a chiral ligand, N-ethyl-N-{[(2S)-pyrrolidin-2-yl]methyl}ethanamine, gave 1-[(4-(bromomethyl)phenyl]-2-(prop-2-yn-1-yloxy)ethanol with a moderate yield and high selectivity.

Abstract Trifluoromethanesulfonamide and its sodium salt reacted with bromoacetonitrile to give a mixture of N-(cyanomethyl)trifluoromethanesulfonamide and N,N-bis(cyanomethyl)trifluoromethanesulfonamide at ratios of 1:1 and 1:14, respectively.

Abstract 3-Aroyl-5-phenylpyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones reacted with 2-oxindole to give products of addition of the C3H group of the enol form of 2-oxindole to the C3a carbon atom of pyrroloquinoxalinetrione, 3-aroyl-2-hydroxy-3a-(2-oxo-2,3-dihydro-1H-indol-3-yl)-5-phenylpyrrolo[1,2-a]quinoxaline-1,4(3aH,5H)-diones. The synthesized compounds are interesting from the viewpoint of medicinal

Abstract Photochemically or thermally initiated reactions of arenesulfonylethynyl(trimethyl)silanes ArSO2C≡CSiMe3 (Ar = Ph, 4-MeC6H4) with 1-R-tricyclo[4.1.0.02,7]heptanes (R = H, Me, Ph) involve addition to the C1–C7 central bicyclobutane bond of the latter with the formation of bicyclo[3.1.1]heptane (norpinane) derivatives with endo(anti)-oriented arenesulfonyl group. A plausible reaction mechanism

Abstract Previously unknown bis-styryl derivatives in which two ortho-styryl-substituted nitrogen heterocycles are linked together through a polymethylene spacer have been designed and synthesized. Spectral and photochemical studies have confirmed high photochemical activity of the synthesized compounds.

Abstract 5-[4-(2-Aryl-1,10b-dihydropyrazolo[1,5-c][1,3]benzoxazin-5-yl)benzylidene]-1,3-thiazolidin-4-ones were synthesized by reactions of 4-[(3-R-2,4-dioxo-1,3-thiazolidin-5-ylidene)methyl]benzaldehydes with 2-(3-aryl-4,5-dihydro-1H-pyrazol-5-yl)phenols and evaluated for antitumor and anti-inflammatory activities.

Abstract A combination of the Passerini reaction and copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC, click reaction) was used to synthesize triazole-containing macrocyclic depsipeptides. The key factors determining the direction of macrocyclization are the chain length of the initial depsipeptide and the presence of rigid fragments therein. The proposed strategy makes it possible to obtain monomeric

Abstract Tricyclo[4.1.0.02,7]heptane reacted with 1-(arenesulfonyl)-2-phenyldiazenes by radical mechanism to give bicyclo[3.1.1]heptane derivatives. Unlike analogous reactions with alkenes, the addition of diazenes occurs readily without a catalyst and yields mainly arylazosulfonation products at the C1–C7 bond of tricyclo-[4.1.0.02,7]heptane. The addition products are capable of undergoing thermal

Abstract Two new approaches have been proposed for the synthesis of 4-hydroxy-1,4-dihydropyrazolo[5,1-c]-[1,2,4]triazines via (1) borohydride reduction of 1-R-4-oxo-1,4-dihydro derivatives and (2) Vilsmeier formylation of 3-tert-butyl-8-methylpyrazolo[5,1-c][1,2,4]triazine. 3-tert-Butylpyrazolo[5,1-c][1,2,4]triazin-1(5)-ium cation has been generated for the first time by treatment of 7-amino-1-ben

Abstract Aryl acetylenes bearing electron-withdrawing groups have been found that can add to azulenes and yield 1,2-substituted heptalenes. Theoretical studies of the reaction mechanism helped to design the candidate molecules that have then been tested in the synthetic work. New heptalenes are obtained by reacting methyl (4-nitrophenyl)propiolate with either 4,6,8-trimethylazulene or guaiazulene,

Abstract A modified procedure has been proposed for the synthesis of 2,7-diphenyl-5,8-dihydro-4H-pyrazolo[5,1-d][1,2,5]triazepin-4-one, and the possibility of transformation of the latter to the pyrazolo[1,5-a]pyrazine system has been demonstrated. Functionalization of 2,7-diphenyl-5,8-dihydro-4H-pyrazolo[5,1-d][1,2,5]triazepin-4-one at the 4-position and fusion of a tetrazole or triazole ring at the

Abstract A convenient procedure has been developed for the synthesis of 3β,28-diacetoxylup-20(29)-en-30-oic acid via oxidation of 3β,28-di-O-acetylbetulin with selenium dioxide in aqueous ethanol on heating, followed by oxidation of 3β,28-diacetoxylup-20(29)-en-30-al thus formed with sodium chlorite in tert-butyl alcohol. The alkylation of 3β,28-diacetoxylup-20(29)-en-30-oic acid with 1,3-dibrompropane

Abstract Methods have been developed for the synthesis of new chiral imino amines and unsymmetrically substituted trans-1,2-diamines based on fumaropimaric acid. The new trans-1,2-diamines were tested as ligands in the copper(II)-catalyzed asymmetric Henry reaction of 4-nitrobenzaldehyde with nitromethane. The effect of substituents on the amino groups on the catalytic activity and asymmetric induction