Abstract The ranges of variation of the rate constant (0.031– 0.153 L·mol–1·s–1), energy of activation (21– 55 kJ/mol), and entropy of activation (88–191 J·mol–1·K–1) for the reaction of benzamide with 3-nitrobenzenesulfonyl chloride in aqueous 1,4-dioxane with a concentration of water of 15–40 wt % have been determined by studying the reaction kinetics in the temperature range 298–313 K. The potential

Abstract A facile synthetic approach to diazepine and/or benzimidazole derivatives has been developed through the reaction of enamine [N1-(1-phenylethenyl)benzene-1,2-diamine] obtained from o-phenylenediamine and acetophenone. Its reaction with isophthaloyl chloride produced bis(1,5-benzodiazepinyl)benzene derivative via cyclization involving the nucleophilic enamino carbon atom, whereas the cyclocondensation

Abstract Derivatives of ethyl 2-cyano-2-[3,4-dicyanopyridin-2(1H)-ylidene]acetate have been synthesized by reaction of 2-chloropyridine-3,4-dicarbonitriles with ethyl cyanoacetate. The synthesized compounds showed solid state fluorescence with the emission maxima located in the range λ 619–641 nm; the emission maxima in solution range from λ 392 to 486 nm, depending on the solvent.

Abstract The addition of 5-(1,4-benzodioxan-2-yl)-4-phenyl-4H-1,2,4-triazole-3-thiol to the C=C double bond of acrylonitrile, acrylamide, and ethyl acrylate afforded 3-[3-(1,4-benzodioxan-2-yl)-4-phenyl-5-sulfanylidene-4,5-dihydro-1H-1,2,4-triazol-1-yl]propanoic acid nitrile, amide, and ethyl ester. The latter was converted to the corresponding hydrazide which reacted with substituted benzoyl chlorides

Abstract Potassium salts of benzylidene and cinnamylidene derivatives of malononitrile trimer were obtained by reactions of substituted benzaldehydes and cinnamaldehydes with malononitrile trimer in aqueous medium under ultrasonic irradiation. The synthesized salts showed solid state fluorescence with the emission maxima located in the region λ 528–740 nm, depending on the substituent in the aromatic

Abstract The reaction of ethyl benzoylacetate with formaldehyde and natural amino acid ester hydrochlorides in acetate buffer (AcONa/AcOH, pH 4.0) at room temperature afforded 41–61% of new 5-benzoylhexahydropyrimidine derivatives. The synthesized compounds were evaluated for their in vitro cytotoxic activity against normal (HEK293) and tumor cell lines (Jurkat, HepG2). T-Lymphoblastic leukemia Jurkat

Abstract An efficient synthesis of fluorinated [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives has been achieved by cyclocondensation of 5-substituted 4-amino-1,2,4-triazole-3-thiols with fluoro-substituted aromatic acids using phosphoryl chloride as a cyclizing agent. The synthesized compounds were characterized by spectroscopic techniques, including IR, 1H NMR, and mass spectra.

Abstract Knoevenagel condensation of betulonic aldehyde with malononitrile afforded 2-[3-oxolup-20(29)-ene-28-ylidene]malononitrile and product of partial hydrolysis of the dinitrile moiety, 2-cyano-3-[3-oxo-28-norlup-20(29)-en-17-yl]prop-2-enamide whose structure was determined by NMR spectroscopy using two-dimensional correlation techniques.

Abstract A procedure has been developed for the direct synthesis of N,N-dimethyloxazolidinium salts by chloromethylation of 2-(dimethylamino)ethanol in the presence of potassium carbonate, followed by intramolecular rearrangement of the resulting quaternary ammonium salt. The synthesis can be accomplished both with and without isolation of the latter.

Abstract New reagents for the synthesis of substituted selenazoles, 3-amino-N-cyclopropyl-3-selanylidenepropanamide and methyl 3-amino-3-selanylidenepropanoate, were obtained by reactions of 2-cyano-N-cyclopropylacetamide and methyl 2-cyanoacetate with hydrogen selenide. The structure of the products was confirmed by IR, 1H and 13C NMR, and mass spectra.

Abstract Poly[2-(2-chloro-1-methylbut-2-en-1-yl)aniline] in polyphosphoric acid at 140–150°C undergoes intramolecular cyclization to produce previously unknown indole polymer, poly(2-ethyl-3-methyl-1H-indole), with 1,5-linkage of monomer units.

Abstract A mechanism has been proposed for the reaction of 1,3-dichloropropene with dipotassium propane-1,3-bis(dithiolate) in the system hydrazine hydrate–potassium hydroxide on the basis of DFT quantum chemical calculations at the B3LYP/6-311++G(d,p) level of theory. The first stage of this reaction has been found to be nucleophilic substitution of one chlorine atom of 1,3-dichloropropene linked

Abstract Opening of the 1,6-anhydro bridge in levoglucosenone by the action of acetic anhydride in the presence of ZnCl2 afforded diastereoisomeric 1,6-di-O-acetyl-3,4-dideoxy-α/β-D-glycero-hex-3-enopyranos-2-uloses, and alcoholysis of the resulting diacetates in methanol, ethanol, and propan-2-ol in the presence of p-toluenesulfonic acid, camphor-10-sulfonic acid, ZnCl2, and HCl was studied. Their

Abstract S-(2-Thiocyanatopropyl) N-alkyl-N-methylcarbamothioates were synthesized from N-alkyl-1,3-oxathiolan-2-imines by reaction with potassium thiocyanate, and their reactions with alcohols under the Ritter conditions afforded 4-substituted N-alkyl-1,3-dithiolan-2-imines.

Abstract The reactions of 2-perfluoroacyl-1H-benzo[f]chromenes and 6,7-dimethyl-3-trifluoroacetyl-4H-chromene with primary aliphatic amines and ammonia afforded a series of enamino ketones containing a (2-hydroxynaphthalen-1-yl)methyl or 2-hydroxybenzyl substituent in the α-position with respect to the carbonyl group. These reactions involved opening of the pyran ring, which followed aza-Michael addition

Abstract A green acetic acid-mediated synthesis of kojic acid derivatives through a multicomponent reaction (MCR) has been developed. This new protocol is simple and efficient; it involves a one-pot reaction of equimolar amounts of kojic acid, aromatic aldehydes, and several active methylene compounds at 90°C in 3 h and results in the formation of a wide range of kojic acid derivatives with high yields

Abstract Amberlyst 15 (A-15) is one of the most common heterogeneous catalysts in organic synthesis. Since its development in 1962, A-15 has proved to be a highly efficient green catalyst in many organic reactions that require acid catalysis. In the last two decades, many reports had been issued that focused on the use of A-15 as a catalyst in heterocyclic synthesis. The use of A-15 implies many advantages

Abstract 5-[3(4)-R-Adamantan-1-yl]salicylic acids [R = H, Alk, Ar, OH, NHC(S)NH2] have been synthesized by electrophilic substitution reactions of hydroxy- and bromoadamantanes with salicylic acid, as well as by reactions of 5-(3-hydroxyadamantan-1-yl)salicylic acid with carbon and nitrogen nucleophiles, in trifluoroacetic acid. The possibility of selective hydroxylation of the adamantane fragment

Abstract 3-[(Alkylsulfanyl)methyl]pentane-2,4-diones reacted with phenylhydrazine in the presence of zinc chloride to give the expected products, 4-[(alkylsulfanyl)methyl]-3,5-dimethyl-1-phenyl-1H-pyrazoles, together with 1-(3-methyl-1-phenyl-1H-pyrazol-4-yl)ethanone. The reaction of 3-[(alkylsulfanyl)methyl]-4-(alkylsulfanyl)butan-2-ones with phenylhydrazine under similar conditions afforded 3,4-

Abstract Geminal difluoroalkenes are readily available building blocks for the synthesis of a broad spectrum of organofluorine compounds. The review summarizes published data on radical reactions involving geminal difluoroalkenes. These processes include addition of a radical species to a double bond or one-electron reduction of the difluoroalkene fragment. Particular emphasis has been placed on photocatalytic

Abstract Binder-free iron- and nickel-containing micro-, meso-, and macroporous zeolites FeHY and NiHY were found to effectively catalyze Knoevenagel condensation of diamantan-3-one with malononitrile, methyl cyanoacetate, and ethyl cyanoacetate at 40°C (5 h) with 94–98% yield.

Abstract A procedure has been proposed for the synthesis of 2-aryl-5-methyl-1,4-dioxanes by alkoxyiodination of halogen-substituted styrenes with allyl alcohol in the presence of crystalline iodine, (NaK)4CaAl6Si30O72 clinoptilolite, and silicotungstic acid sodium salt Na4SiW12O40·19H2O in aqueous medium.

Abstract A new procedure has been developed for the synthesis of 3,3′,3″-nitrilotripropionic acid (NTP) by reaction of formamide with acrylic acid in a solvent under pressure 100–130°C. The product structure was confirmed by IR and 1H and 13C NMR spectra, X-ray diffraction data, and elemental analysis.

Abstract Allobetulin was converted to 3β-acetoxy-21β-acetyl-20β,28-epoxy-18α,19β-ursane, followed by reduction of the acetyl fragment and acid-catalyzed dehydration product. The structure of the obtained triterpenoid containing a trans-ethylidene substituent on the E ring was determined using two-dimensional 1H–1H COSY, 1H–1H NOESY, 1H–13C HSQC, 1H–13C HMBC correlation techniques.

Abstract Stereoselective synthesis of sarmentine has been achieved via iron-catalyzed cross-coupling of pentylmagnesium bromide with ethyl (2E,4E)-5-chloropenta-2,4-dienoate obtained by one-pot oxidation–olefination of readily available (2E)-3-chloroprop-2-en-1-ol.

Abstract Diazotization of 2-, 3-, and 4-aminopyridines in the presence of both racemic camphor-10-sulfonic acid and its pure enantiomers led to the formation of the corresponding pyridyl camphorsulfonates in moderate yields. Pyridyl camphorsulonates were found to be more reactive in alkaline alcoholysis than analogous pyridyl trifluoromethanesulfonates and pyridyl p-toluenesulfonates.

Abstract A promising area of modern coordination and supramolecular chemistry is the synthesis of biologically active compounds of germanium and creation of effective drugs, biomaterials, and enzyme modulators based thereon. The present review deals with biologically active compounds of germanium(IV) and contributes to the solution of problems of synthesis, physicochemical analysis, and prediction

Abstract The reaction of tris(8-carboxy-2,2,6,6-tetramethylbenzo[1,2-d;4,5-d′]bis[1,3]dithiol-4-yl)methanol, diamagnetic precursor of Finland trityl radical} with trifluoroacetic acid gave the corresponding triarylmethyl cation. Nucleophilic quenching of this cation with triethyl phosphite generated trityl radical containing a diethyl phosphonate moiety, and hydrolysis of the latter to phosphonic acid

Abstract A simple synthetic protocol have been developed for the preparation of novel N-(4-benzylidene-5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-1-yl)-N′-phenylthiourea derivatives by the reaction of 4-benzylidene-2-phenyl-4,5-dihydro-1,3-oxazol-5-ones with N-(3-chloro-4-fluorophenyl)- and N-[3-(trifluoromethyl)phenyl)hydrazinecarbothioamides. The synthesized imidazolones have been characterized by using

Abstract The reaction of maleopimaric and dihydroquinopimaric acid chlorides with potassium thiocyanate gave the corresponding acyl isothiocyanates which were treated with primary amines and L-amino acid methyl esters to afford new diterpenoid thiourea derivatives.

Abstract A new chiral 10,11-didehydro analog of epothilone D with isosteric substitution in the C15–C3 fragment of natural epothilones has been synthesized.

Abstract Osthol [7-methoxy-8-(3-methylbut-2-en-1-yl)chromen-2-one] isolated from Prangos pabularia was used as a starting material for the synthesis of its various derivatives via modifications of the lactone ring. The resulting compounds were fully characterized by spectral techniques and evaluated for their anticancer activity against Hep-G2 (human hepatoma), HeLa (cervical carcinoma), U-87 (brain

Abstract The first nickel-catalyzed phosphorylation of aryltrimethylammonium tetrafluoroborates with the formation of C–P bond instead of C–N has been developed. Starting from easily available and inexpensive aromatic amines, a variety of important arylphosphonates have been synthesized in moderate to excellent yields.

Abstract New Mannich bases were synthesized from chiral norbornenylmethanol, secondary amines, and formaldehyde. Their structure was confirmed by elemental analyses and IR, 1H and 13C NMR, and mass spectra. The products were optically active (dextrorotatory), and they showed high antimicrobial activity against Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and yeast-like fungi of the

Abstract A simple and efficient protocol for the synthesis of benzimidazolylimidazo[4,5-b]indoles has been developed through the condensation of 2-aminobenzimidazole, aromatic aldehyde, ammonium acetate, and isatin via multicomponent reaction strategy using ceric ammonium nitrate as catalyst. The key advantages of the four-component reaction are easy work-up, high yield, short reaction time, and environmentally

Abstract 2-Substituted benzimidazole derivatives were synthesized by condensation of o-phenylenediamine with the corresponding substituted benzaldehydes and were alkylated at the nitrogen atom using C3–C10 alkyl bromides in the presence of tetrabutylammonium hydrogen sulfate as a phase-transfer catalyst and 30% aqueous potassium hydroxide as a base. The synthesized derivatives were characterized by

Abstract Three-component 1,3-dipolar cycloaddition reactions between isatin, benzylamine, and α,β-unsaturated ketones at room temperature afforded substituted spiro[indole-3,2′-pyrrolidine] derivatives with good yields. In some cases, only one diastereoisomer was formed. The reaction involved in situ generation of azomethine ylide from isatin and benzylamine. The possibility of formation of different

Abstract The reaction of β-keto esters or acetylacetone with alkyl azides in the system K2CO3/DMSO proved to be a convenient method of synthesis of tri- and disubstituted 1-alkyl-1H-1,2,3-triazoles.

Abstract The review covers the state of the art in methods of synthesis of acyclic geminal bis-peroxides, including bis-hydroperoxides, bis(1-hydroperoxyalkyl) peroxides, and 1-hydroperoxyalkyl 1-hydroxyalkyl peroxides. Most attention has been paid to the literature since 2000. This period of time is characterized by studies of mechanisms of formation of peroxides and hence by the development of effective

Abstract New benzimidazole derivatives were synthesized by reacting substituted phenacyl bromides with 1H-benzimidazole-2-thiols. The synthesized compounds were characterized through 1H and 13C NMR and high-resolution mass spectra. Their evaluation for α-amylase activity revealed inhibitory potential with IC50 values ranging from 1.20±0.05 to 19.10±0.30 μM against IC50 = 1.70±0.10 μM for the standard

Abstract A convenient and highly efficient, catalysts-free synthesis of benzimidazoles in an aqueous medium has been developed. The conditions of the synthesis were optimized, and its scope was successfully extended to various substrates with good to excellent yields. The experimental procedure is simple, and the products can be isolated by filtration followed by recrystallization from water.

Abstract The reaction of carboxamides with phosphorus trichloride under heating at 75–80°C for 1 h in the presence of a 4-dimethylaminopyridine catalyst was used to synthesize imidoyl chlorides in yields of 63–99%.

Abstract Biological active compounds on the basis of 3-amino-5-phenylthiazolidin-2-iminium bromide were synthesized, and their biological activity was studied. The structures of the synthesized compounds were confirmed by 1H and 13C NMR spectroscopy and X-ray diffraction analysis.

Abstract The reaction of 1,3,5,7-tetramethyladamantane with fuming nitric acid leads to a mixture of 1,3,5,7-tetramethyladamantane-2,6-dione and syn/anti-6-nitroxy-1,3,5,7-tetramethyladamantan-2-one. 1,3,5,7-Tetramethyladamantane has an abnormally low reactivity due to the presence of methyl groups in the bridgehead positions of the cage.

Abstract A convenient method of synthesis of fused heterocyclic systems, involving cyclization of the reaction products of 2-aryl-1,2,3,4-tetrahydroquinolines with triphosgene, chloroacetyl chloride, and oxalyl chloride in the presence of anhydrous AlCl3 in carbon disulfide or dichloroethane.

Abstract The review describes the most common macrolactonization reactions, including the activation of one and/or another terminal functional group in a seco acid in the synthesis of natural and biologically active compounds, and also analyzes the advantages and disadvantages of the described macrolactonization methods.

Abstract Two new pharmacologically active series of N-alkyne-substituted indole–thiazoles and C-alkyne-substituted benzylidene–thiazoles were synthesized by a two-step procedure involving initial reactions of thiosemicarbazide with, respectively, [1-(prop-2-yne-1-yl)oxy)-1H-indol-3-yl]formaldehyde and 2-(prop-2-yne-1-yloxy)benzaldehyde, followed by the reactions of the resulting hydrazine-1-carbothioamides

Abstract The first example of the sulfinylation of indoles with arylsulfinamides in water in the presence of trifluoroacetic acid as a promoter is described. The reaction occurs smoothly at room temperature under environmentally benign conditions without any catalyst, additive, ligand, or organic solvent. The developed sulfoxide synthetic protocol is attractive due to the use of water as the solvent

Abstract An efficient method for the preparation of trihalomethyl (Cl, Br) ketones by the oxidation of trihalomethyl carbinols with 2-iodoxybenzoic acid in tert-butanol under heating has been developed. A series of trihalomethyl ketones have been synthesized through a simple, convenient, and environmentally friendly method with excellent yields.

Abstract A comparative study of the catalytic efficiency of Pd(0) and Cu(I) complexes in the reactions of adamantanamines with fluoro- and trifluoromethyl-substituted 2-bromopyridines was carried out using previously optimized catalytic systems. It was shown that in the absence of steric hindrances in the starting compounds, the copper and palladium catalysts were comparable in efficiency. In some

Abstract A direct selective approach to the oxidation of sulfides to sulfoxides and sulfones with H2O2 in moderate to good yields is developed. The reaction proceeds in the presence of 2 mol % of VO(acac)2 at room temperature. All sulfoxides and sulfones were detected by gas chromatography, and the molecular structures of 2-methylbenzyl 4-methylphenyl sulfone, 4-methylbenzyl 4-methylphenyl sulfone

Abstract The reactions of 1-isobutyl-4-(1-isocyanatoethyl)benzene with various amines and of 1-(4-isobutylphenyl)ethanamine with halogenated aromatic isocyanates gave a series of ureas containing an ibuprofen fragment in their structure. The yields of the target product yields were up to 95%. The synthesized ureas are potential multitarget inhibitors of soluble epoxide hydrolase (sEH) and cyclooxygenase

Abstract The COVID-19 pandemic has forced scientists all over the world to focus their effort on searching for targeted drugs for coronavirus chemotherapy. The present review is an attempt to systematize low-molecular-weight compounds, including well-known pharmaceuticals and natural substances that have exhibited high anti-coronavirus activity, not in terms of action on their targets, but in terms

Abstract New polyconjugated systems containing iminodihydrofuran and benzene rings were successfully synthesized by reaction of 2-imino-2,5-dihydrofuran-3-carboxamide with 4-aminobenzohydrazide in acetic acid.

Abstract Acylation of 1,3-benzothiazol-6-amine with furan-2-carbonyl chloride in propan-2-ol gave N-(1,3-benzothiazol-6-yl)furan-2-carboxamide which was converted to the corresponding thioamide by treat­ment with excess P2S5 in anhydrous toluene. The subsequent oxidation with potassium hexacyanoferrate(III) in alkaline medium afforded 2-(furan-2-yl)benzo[1,2-d:4,3-d′]bis[1,3]thiazole which was subjected

Abstract Previously unknown functionally substituted 1,1′-(9-selenabicyclo[3.3.1]nonane-2,6-diyl)dipyridi­nium dibromides were synthesized in 90–98% yields by one-pot condensation of selenium dibromide, cyclo­octa-1,5-diene, and substituted pyridines.

Abstract Ullmann reaction of 2-[(6-chloroquinoxalin-2-yl)oxy]benzonitrile with 4-tert-butylphenol unexpect­edly afforded 2-(4-tert-butylphenoxy)-6-chloroquinoxaline instead of the corresponding 6-substituted deriva­tive. Different phenols were used to check the nucleofugality of 2-cyanophenoxy group in the 2-position of quinoxalines, so that 2-cyanophenoxy group can be regarded as an alternative to

Abstract The dammarane triterpenoid hollongdione was modified at the C3 and C20 positions to obtain 3β,20α-dihydroxy and (3E,20ZE)-3,20-dihydroxyimino derivatives whose structure was confirmed by X-ray analysis.

Abstract Conjugates of hydroxy- and acetoxybenzoic acids with dipeptides based on 4-aminobutanoic acid and glycine were synthesized through hydroxy(acetoxy)benzoyl chlorides and 4-[hydroxy(acetoxy)benzoyl­amino]butanoyl chlorides as intermediate products. Acyl chlorides were prepared by treatment of the corre­sponding acids with oxalyl chloride in the presence of dimethylformamide at a ratio of 1:1

Abstract Methyl 3-(3,6-diaryl-1,2,4-triazin-5-ylamino)thiophen-2-carboxylates were synthesized in 70–75% yield by solvent-free reaction of methyl 3-aminothiophene-2-carboxylate with 3,6-diaryl-1,2,4-triazine-5-carbo­nitriles as a result of nucleophilic substitution of the cyano group in the latter.