Synthesis and properties of 5-(5-nitro-2-furyl)thiazolines

The reactions of 2-amino-4-methyl-5-(5-nitro-2-furyl)thiazole with excess methyl iodide leads to 3,4-dimethyl-2-methylamino-5-(5-nitro-2-furyl)thiazolium iodide, which is converted to 2-imino-3,4-dimethyl-5-(5-nitro-2-furyl)thiazoline under the influence of bases. The iminothiazoline structure was proved by comparison of the spectral characteristics of its acetyl derivative and the isomeric 2-(N-acetyl-N-methyl) amino-4-methyl-5-(5-nitro-2-furyl)thiazole. The pKa values of 2-amino-4-methyl-5-(5-nitro-2-furyl)thiazole and 3,4-dimethyl-2-imino-5-(5-nitro-2-furyl)-thiazoline were determined, and the constant of the aminothiazole-iminothiazoline tautomeric equilibrium was calculated.Translated from Khimiya Geterosiklicheskikh Soedinenii, No. 10, pp. 1337–1340, October, 1985.     

Synthesis and properties of 2-amino-5-(5-nitro-2-furyl) thiazole derivatives

The hydrochlorides of the corresponding 2-aminothiazoles, which were converted to the free bases, were obtained by hydrolysis of 2-acylamino-5-(5-nitro-2-furyl) thiazoles. Reactions that take place at the amino group of 2-amino-5-(5-nitro-2-furyl)thiazoles are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1038–1041, August, 1985.     

Reactions of 1-amino-2-nitroguanidine with 2-aryl(hetaryl)-1-nitro-1-ethoxycarbonyl(benzoyl)ethenes

Reactions of 1-amino-2-nitroguanidine with 2-aryl(hetaryl)-1-nitro-1-ethoxycarbonyl(benzoyl)-ethenes proceed via initial formation the aza-Michael product, are accompanied by liberation of nitroacetic ester (or nitroacetophenone), and result in N-aryl(hetaryl)methylidene-N-(2-nitroguanidino)amines.     

A Convenient Synthesis of 2-Acyl-2-alkyl-3-nitro-2H-chromenes

Treatment of 2-hydroxybenzaldehydes by potassium t-butoxide in THF at 0°C, followed by addition of β-nitroenones 1 affords 2-acyl-2-alkyl-4-hydroxy-3-nitrochromanes 3. Subsequent treatment of these nitro alcohols by silica gel at 50°C leads to the desired 2-acyl-2-alkyl-3-nitro-2H-chromenes 4 in good yields.     

Synthesis of new 1-C-(2-furyl)-and 3-C-(2-furyl)-hexopyranosides and 3-C-(2-furyl)-daunorubicin analogs

Summary Reaction of furan with 3,4-di-O-acetyl-L-rhamnal (1) afforded a mixture of epimeric 3-C-(2-furyl) glycals3 and4 and 1-C-(2-furyl)-hex-2-enopyranoses5 and6. Glycals3 and4 were transformed to 2-deoxy-glycosides9–13 and 3-deamino-3-C-(2-furyl)daunorubicines15 and16. Hex-2-enopyranosyl5 wascis hydroxylated with osmium tetroxide/N-methylmorpholine N-oxide to C-glycoside14.On leave from Pharmaceutical Research Institute, Warsaw, Poland     

Synthesis and X-Ray Diffraction Study of 2-(2-Acyl-1-phenylethenyl)pyrroles

Pyrroles add to 2-acyl-1-phenylacetylenes on the surface of silicon dioxide at 20-90°C affording structurally stable Z-isomers of 2-(2-acyl-1-phenylethenyl)pyrroles containing a strong intramolecular hydrogen bond. The geometry of these molecules was established by X-ray diffraction analysis of a single crystal of 2-(2-benzoyl-1-phenylethenyl)-4,5,6,7-tetrahydroindole.     

Synthesis of 1-(2-furyl)-2-nitropropen-3-ones

1-(2-Furyl)-2-nitropropen-3-ones were synthesized by reaction of nitrogen tetroxide with a number of , -unsaturated furylcarbonyl compounds. The 5-nitrofuryl derivative was obtained from 1-(2-furyl)-3-(4-methoxyphenyl)propen-3-one when the excess amount of N₂O₄ was increased. Replacement of bromine by a nitro group in the furan ring is observed in the case of the 5-bromofuryl derivative.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1604–1606, December, 1977.     

Catalyst- and steric-controlled alkenylation via chemoselective C-H activation and C-Br activation in Heck reaction of methyl 1-(2-bromoaryl)-3-(2-furyl/thienyl)-5-oxopyrrolidine-2-carboxylates and diethyl 1-(2-bromoaryl)-3-(2-furyl/thienyl)-5-oxopyrrolidine-2,2-dicarboxylate derivatives

Pd(II)-catalyzed alkenylation of methyl 1-(2-bromoaryl)-3-(2-furyl/thienyl)-5-oxopyrrolidine-2-carboxylate derivatives 1(a-d) resulted in the formation of 3(a-d) exclusively via C-H activation in the heteroaryl moiety. Similar observations were observed for the corresponding diester analogues 4(a-d) to form 5(a-d). Normal Heck reaction, however, was observed in the case of 1(a-f) to furnish 2(a-f) when the reaction was carried out with Pd(0) catalyst generated in situ. Pd(0)-catalyzed vinylation of 4(a-f) via C-Br oxidation, however, failed due to steric reason.     

Synthesis of 2-Acyl- and 2-Sulfonylbenzisoselenazol-3(2H)-ones

Synthesis of two new groups of organoselenium compounds: 2-acyl-and sulfonylbenzisoselenazol-3(2H)-ones (3, 4), potential immunostimulants, in two alternative ways was elaborated. One of them was based on the reaction of 2-chlorobenzoyl chloride (2) with primary amides while the second one involved N-acylation or N-sulfonylation of benzisoselenazol-3(2H)-one (5) with acid chlorides. Two exceptions from general reaction of dichloride 2 with amides were observed. Thioacetamide produced 2,1-benzothiaselenophenone (6), and urea gave 6,7-benzo-2,4-diaza-1-selenacyclohepta-3,5-dione (7).     

Synthesis and properties of 2-(2-furyl)benzothiazole

The electrophilic reactions (nitration, bromination, hydroxymethylation, formylation, acylation) and radical substitution reactions (nitration, arylation) of 2-(2-furyl)benzothiazole have been studied. It was found that all of the reactions occur at position 5 of the furan ring. Only nitration in PPA gave the 5',6-dinitro derivative. Quantum-chemical calculation data for the electron density distribution in the neutral and protonated 2-(2-furyl)benzothiazole molecules are given. Dedicated to Boris Aleksandrovich Trofimov on his 70^th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1331–1338, September, 2008.     

Synthesis of 2-(3-furyl)-1H-benzimidazoles from 2-phenacyl-1H-benzimidazoles

C-Alkylation at the active methylene group of 2-phenacyl-1H-benzimidazoles with phenacyl bromides proceeds highly selectively with the formation of the corresponding 1,4-diketones, which on heating with hydrochloric acid are cyclized with the formation of the previously unknown 2-(2,5-diaryl-3-furyl)-1H-benzimidazoles. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1637–1645, November, 2007.     

Synthesis of some substituted 2- and 4-[2′-(5″-nitro-2″-furyl)vinyl]-quinolines

A series of 2- and 4-[2-(5-nitro-2-furyl)vinyl]quinolines were synthesized by catalytic condensation of 5-nitrofurfural with 2- and 4-methylquinolines. 2-Methylquinoline (quinaldine) and its substituted derivatives also react when the starting reagents are fused directly.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 253–255, February, 1976.     

Synthesis and Structure of 1-Bromo-1-nitro-2-piperidino(cyclohexylamino)-2-phenylethenes

A preparation method was developed for new representatives of halonitroenamines, 1-bromo-1-nitro-2-piperidino(cyclohexylamino)-2-phenylethenes. Both molecules possess E configuration and are of high polarity.