Synthesis and properties of furanyl 1,3-dioxolanes. 2. Synthesis of new derivatives of furanyl 1,3-dioxolanes

New derivatives of furnayl 1,3-dioxolanes containing amino, ammonium, alkoxy, and vinyl groups in the dioxolane fragment were synthesized.For Communication 1, see [1].Translated from Khimiya Geterotisiklicheskikh Soedinenii, No. 3, pp. 325–328, March, 1993.     

Synthesis of amino sugars via isoxazolines: Nitrile oxide-furan adducts as key intermediates in the isoxazoline route towards novel amino sugar derivatives

New variations for 1,3-dipolar nitrile oxide cycloadditions to reluctant dipolarophiles furan and 2-methylfuran are presented. The furoisoxazoline adducts 6 and 7 are shown to represent highly advanced, yet versatile precursors for derivatives of novel C₆ and C₇ amino sugar derivatives, accessible by subsequent highly stereoselective modification (addition of HO/OCH₃ or HO/OH) and/or LiAlH₄ reduction.     

Synthesis of amino sugars via isoxazolines the concept and one application: nitrile oxide/furan adducts

Aliphatic nitrile oxides cycloadd to furans to afford amino sugar precursors 1. Oxidation by m-chloroperbenzoic acid and/or LiA1H₄ reduction give rise stereoselectively to derivatives of the xylo and ido series, 2 – 4, with 3 to 5 adjacent chiral centres.     

Synthesis and biological activities of novel 2-amino-1,3-thiazole-4-carboxylic acid derivatives

A series of novel 2-amino-1, 3-thiazole-4-carboxylic acid derivatives were designed and synthesized. Their structures were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and HRMS or elemental analysis. Biological activities of all title compounds including fungicidal activity and antivirus activity were evaluated systematically. Preliminary bioassays indicated that these compounds exhibited good fungicidal activity at 50 μg/mL, compounds 4b and 4i exhibited over 50% activity against six fungi tested. Most compounds showed good activity against TMV with different models in vivo at 100 μg/mL. Compounds 4c and 4e stood out with high effects against TMV in vivo in all models tested, including protective, inactivative, curative, and inductive activities. These data demonstrate a new strategy for fungi and virus control.     

Synthesis of 2-amino-4-(2-thienyl)thiazole and its derivatives

The bromination of substituted methyl 2-R-thienyl ketones with bromine in chloroform yielded bromomethyl 2-thienyl ketones. The latter were converted to quaternary pyridinium salts and 2-amino-4-(2-thienyl)thiazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1369–1371, October, 1971.     

Heterocyclic compounds from 2-(alkoxycarbonylcyanomethylene)-1,3-dioxolanes

2-(Alkoxycarbonylcyanomethylene)-1,3-dioxolanes reacted with hydrazines and hydroxylamine to yield 1-substituted 4-alkoxycarbonyl-5-amino-3-(2′-hydroxyethoxy)pyrazoles and 4-alkoxycarbonyl-5-amino-3-(2′-hydroxyethoxy)isoxazoles respectively. With guanidine and benzamidine 2-substituted (R = NH₂, C₆H₅) 5-cyano-6-(2′-hydroxyethoxy)pyrimidin-4-ones were obtained. Reaction of 2-(cyanomethoxycarbonylmethylene)-1,3-dioxolane with 1,3-diaminopropane afforded 2-(cyanomethoxycarbonylmethylene)-1,3-hexahydro-pyrimidine whereas treatment of the same compound with 4,5-dimethyl-1,2-phenylenediamine gave 2-(cyanomethoxycarbonylmethylene)-5,6-benzimidazoline. The structures of pyrazoles and pyrimidones were assigned on the basis of ¹H-{¹H} and ¹³C-{¹H}-nOe experiments.     

Synthesis of new 4-phosphorylated derivatives of 5-amino-1,3-oxazole

The N-1,1,1,2-Tetrachloroethylamides were found to react with diethyl amidophosphites via the Arbuzov reaction to afford N-substituted amides of ethyl 1-acylamino-2,2,2-trichloroethylphosphonic acids. A convenient method for the synthesis of new 4-phosphorylated 5-amino-1,3-oxazoles on their basis was developed.     

Polymerization of 2-(chlorinated methyl)-4-methylene-1,3-dioxolanes

The polymerizations of the novel 2-(chlorinated methyl)-4-methylene-1,3-dioxolanes derived from mono-, di-, and trichloroacetaldehyde were investigated. Poly-2-trichloromethyl-4-methylene-1,3-dioxolane was of particular interest because of its high hydrolytic stability and nonflammability. The monomers could be polymerized with cationic catalysts via the methylene functions without cleavage of the dioxolane rings. This selectivity was due to the acetal-stabilizing negative substituents and to the use of Lewis acid complexes of low reactivity as catalysts. In contrast to previously reported poly-4-methylene-1,3-dioxolanes, the title polymers were high-melting colorless solids of good to excellent fire resistance.     

2-芳基-(4S,5S)-4,5-双(胺甲酰基)-1,3-二氧戊环的合成

以D-酒石酸二乙酯和芳香醛为原料,经缩醛化、氨解两步反应合成了15个未见文献报道的适合工业化生产庚铂类似物的关键中间体——2-芳基-(4S,5S)-4,5-双(胺甲酰基)-1,3-二氧戊环,产率49%～70%,其结构经1HNMR和MS表征。     

Synthesis and stereochemistry of 2, 2-dimethyl-5-aryl-4-benzoyl-1,3-dioxolanes

The reaction of 3-aryl-2-benzoyloxiranes with acetone in the presence of catalytic amounts of boron trifluoride etherate leads to the formation of mixtures of cis and trans isomers (3070) of 2,2-dimethyl-5-aryl-4-benzoyl-1,3-dioxolanes, the structures and stereochemistry of which were established on the basis of data from their PMR spectra, measurement of the Overhauser nuclear effect, and some chemical transformations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 888–891, July, 1979.     

Synthesis of unsymmetrical 2-(2-vinyl-4H-chromen-4-ylidene)malononitrile dyes via Knoevenagel reaction

A series of new chromophores based on 4-(dicyanomethylene)-2-vinyl 4H-chromenes was synthesized and their physical properties (UV–Vis, NMR, mass spectrometry) were studied. The chromophores show moderate or good solubility in organic solvents. Solvatochromism was investigated for compounds in solvents of low (1.4-dioxane, chlorobenzene, methylene chloride) and high polarity (acetone, acetonitrile). The calculations of the first hyperpolarizability (β) was performed using M052X/6-31+G(d) approximation. Chromophore’s molecules are characterized by high calculated values of the first hyperpolarizability (β) that is only 15% lower than that of FTC analogs.     

Synthesis of 4-hetaryl-substituted 5-amino- and 5-sulfanyl-1,3-oxazole derivatives

Previously unknown 5-amino- and 5-sulfanyl-1,3-oxazole derivatives containing a 1,3,4-oxadiazole, 1,3,4-thiadiazole, or 1,2,4-triazole fragment at C⁴ were synthesized from accessible 1,3-oxazole-4-carboxylic acid hydrazides.     

Synthesis of substituted 2-amino-4H-1,3-oxazines

4,4,6-Trimethyl-2-methylarylamino-4H-1,3-oxazines were synthesized by intramolecular cyclization of N-oxoalkyl-S-methylisothioureas.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 764–767, June, 1974.     

Synthesis of 7-iodo(arylsulfanyl)methyl-7,8-dihydro-[1,3]thiazolo[2,3-i]purinium pentaiodide (perchlorates) and their transformation into 4-amino-5-(1,3-thiazol-2-yl)imidazole derivatives

Intramolecular electrophilic cyclization of 6-allylsulfanylpurine by the action of iodine and arenesulfenyl chlorides gave 7-iodomethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium pentaiodide and 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates, respectively. 7-Iodomethyl-7,8-dihydro-[1,3]thiazolo[2,3-i]purin-6-ium iodide reacted with sodium and potassium alkoxides to produce alkyl N-[5-(4-methyl-1,3-thiazol-2-yl)-1H-imidazol-4-yl]formimidates, and its reaction with secondary cyclic amines afforded 5-(4-methyl-1,3-thiazol-2-yl)-N-[morpholin-4-yl(or piperidin-1-yl)methylidene]-1H-imidazol-4-amines. Successive treatment of 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates with sodium acetate and morpholine led to the formation of 5-(4-arylsulfanylmethyl-4,5-dihydro-1,3-thiazol-2-yl)-N-(morpholin-4-ylmethylidene)-1H-imidazol-4-amines.