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Документ Synthesis of novel pyrazole based aurones(2022) Myshko, Andrii; Mrug, Galyna; Kondratyuk, Kostyantyn; Demydchuk, Bohdan; Bondarenko, Svetlana; Frasinyuk, MihayloAs we found, simplest pyrazole based aurone analogs could be obtained by Claisen-Shmidt condensation of hydroxylated or alkoxylated benzofuran-3(2H)-ones and 3(5)-pyrazolecarboxaldehyde or 4-pyrazolecarboxaldehyde under action of KOH in EtOH. For the synthesis of hydroxypyrazole based aurone analogs we choose condensation of masked enaminones as synthetic equivalent of 3-hydroxy-4-formylpyrazoles/4-formylpyrazolin-3-ones. Target aurones were obtained by refluxing of benzofuranones with masked aldehydes in acetic acidДокумент Synthesis of homoisoflavonoids with a coumarin moiety and coumarin-pyrazole or coumarin-isoxazole hybrids based on them(2022) Myshko, Nataliia; Mrug, Galyna; Bondarenko, Svetlana; Frasinyuk, MihayloIn this research in the oxa-Diels–Alder reaction of thermally generated ortho-quinone methides from 3-aryl-8-(N,N-dimethylaminomethyl)coumarines with (2E)-3-(N,N-dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-ones and the subsequent cascade of reactions were obtained 8-[4-oxo-4H-chromen-3-yl)methyl]-7-hydroxy-3-phenyl-2H-chromen-2-ones. Synthesis of pyrazole-3-arylcoumarin hybrids was performed by recyclization of chromone core of homoisoflavonоids under hydrazine actions. Target isoxazoles were synthesized by the reaction of homoisoflavonоids with hydroxylamine hydrochloride in ethanol in presence of DBUДокумент Synthesis of Coumarin-4-ylethyl Phosphonic Acid Derivatives(2019) Kondratyuk, Kostyantyn; Dluzhevskyi, Viacheslav; Mrug, Galyna; Bondarenko, Svetlana; Brovarets, Volodymyr; Frasinyuk, MihayloWe investigated the reaction of 7-methoxy-4-chloromethylcoumarin and ethyl (diethoxyphosphoryl) acetate in various solvents in the presence of various bases, which led us to the synthesis of ethyl 2-(diethoxyphosphoryl)-3-(7-methoxy-2-oxo-2H-chromen-4-yl) propanoate. It was found that the ratio of 4-chloromethylcoumarin / ethyl (diethoxyphosphoryl) acetate / sodium hydride 1: 2: 2 using dimethylformamide as the solvent was optimal. Alkaline hydrolysis of ester with lithium hydroxide excess affords new 2-(ethoxyphosphoryl)-3-(7-methoxy-2-oxo-2H-chromen-4-yl) propionic acidДокумент Trifluoroacetylation of 2-Methyl- and 2-Ethylchromones: A Convenient Access to 2-Trifluoroacetonyl Chromones(2019) Biletska, Iryna; Mrug, Galyna; Frasinyuk, Mihaylo; Bondarenko, Svetlana; Sviripa, VitaliyWe elaborated simple and efficient method for the synthesis of 2-(3,3,3-trifluoroacetonyl) chromones and isoflavones. This method involves an initial in situ generation of the vinyl ethers from 2-methyl- or 2-ethylchromones/isoflavones and their subsequent acylation with trifluoroacetic anhydride in the presence of CF3COOK. This pathway provides convenient access to novel fluorinated analogs of naturally occurring chromones with good yieldДокумент One-Pot Synthesis of B-Ring ortho-Hydroxylated Homoisoflavonoids(2019) Myshko, Nataliia; Bondarenko, Svetlana; Mrug, Galyna; Sviripa, Vitaliy; Frasinyuk, MihayloA reliable method for the synthesis of B-ring hydroxylated homoisoflavonoids and 3-hetarylmethyl chromones has been developed. The method involves an initial oxa-Diels-Alder reaction of ortho-quinone methides generated from aryl/hetaryl-substituted ortho-(N,N-dimethylaminomethyl)phenols with (2E)-3-(N,N-dimethylamino)-1-(2-hydroxyphenyl)-prop-2-en-1-ones and the subsequent cascade of reactions. This synthetic strategy avoids conventional multistep protocols and does not require the protection of hydroxyl groups, thus allowing the facile synthesis of a library of various aromatic and heterocyclic analogs of naturally occurring homoisoflavonoidsДокумент Synthesis of pyrazole-containing xyloketal-like compounds(2018) Mrug, Galyna; Bondarenko, Nataliia; Bondarenko, Svetlana; Frasinyuk, MihayloUnique metabolites named xyloketal A – H which containing fused bezopyran and furan rings with acetal function were Isolated from mangrove fungus Xylaria sp.The biosynthesis and chemical syntheses of these and related compounds are based on inverse-electron-demand Diels-Alder reaction. We developed synthesis of pyrazole derivatives of 2,3,3a,9a-tetrahydro-4H-furo[2,3- b]chromene heterocyclic system which presents in natural acetals. Interaction of thermally generated ortho-quinone methides from isoflavone Mannich bases with 2,3- dihydrofuran or 3,4-dihydro-2H-pyran led to formation fused acetals. Selective cleavage of pyranone ring compounds by hydrazine treatment led to the formation of xylokeketal-like–pyrazole hybridsДокумент Chain-chain tautomerism of ω-aminoalcohol aminomethyl derivatives(2018) Danylchenko, V. Ye.; Bondarenko, Svetlana; Mrug, Galyna; Kondratyuk, K. M.; Frasinyuk, MihayloThe aminomethylation reaction of 2-naphtol, umbelliferon, and 7- hydroxyisoflavones using ω -aminoalcohols and paraformaldehyde was studied. The products of reaction exist as tautomeric mixtures which was confirmed by 2D NOESY spectra. The ratio of tautomers depends on carbon chain length of ω-aminoalcohol, solvent, and pH. The major form of 2-aminoethanol derivatives is 1,3-benzoxazine. However, low-polar solvents shift equilibrium toward 1,3-oxazoline form. Derivatives of 3-aminopropanol are preferably exist as 1,3-oxazoline form in all solvents. The mixture of tautomers also was indicated for 4-aminobutanol derivatives, but 5-aminopentanol derivatives exist only in 1,3- benzoxazine formДокумент Synthesis of 2H,10H-pyrano[2,3-f]chromen-2,10-diones and coumarinpyrazole or coumarin-pyrimidine hybrids based on them(2023) Myshko, Nataliia; Mrug, Galyna; Bondarenko, Svetlana; Frasinyuk, MihayloIn the oxa-Diels–Alder reaction of 8-[(2E)-3-(dimethylamino)prop-2-enoyl]-7-hydroxy-2H-chromen-2-one with thermally generated ortho-quinone methides from 2-(N,N-dimethylaminomethyl)phenols and the subsequent cascade of reactions were obtained 2H,10H-pyrano[2,3-f]chromen-2,10-diones. The synthesis of pyrazole–7-hydroxycoumarin hybrids was performed by recyclization of pyranochromone core under hydrazine actions. Reaction of 2H,10H-pyrano[2,3-f]chromen-2,10-diones with guanidine hydrochloride or related N,N-disubstituted derivatives as 1,3-bidentate nucleophiles affords amino-, dimethylamino-, 1-piperidino-, and 4-morpholino substituted pyrimidine-coumarin hybridsДокумент Reaction of ortho-Quinone Methides with Amphiphilic Nucleophiles(2023) Myshko, Andrii; Mrug, Galyna; Myshko, Ivan; Bondarenko, Svetlana; Frasinyuk, MihayloIn continuing our studies on flavonoid-like scaffolds as privileged structures in medicinal chemistry, we studied the reaction of isoflavonoid derivatives with amphiphilic nucleophiles with heterocyclic cores. The direction of the reaction significantly depends on starting phenols, nucleophiles, and reaction conditions. Thus, applying phenolic Mannich bases led to formation of isoflavone-heterocycle hybrid via thermal formation of ortho-quinone methides in aprotic solvents and subsequent Michael addition