SYNTHESIS AND RADICAL POLYMERIZATION OF BIFUNCTIONAL MALEIMIDES WITH DIFFERENT FUNCTIONAL REACTIVITIES

Three bifunctional N-phenylmaleimide derivatives, N-[4-(2-hydroxy-3-methacryloyloxy propyloxycarbonyl)phenyl]male-imide (GMAPMI, 1), N-(4-methacryloyloxyphenyl) maleimide (MAPMI, 2) and 4-(4-maleimidobenzoyloxy)styrene (MIBOSt, 3) having radically polymerizable maleimide and vinyl groups together have been synthesized and polymerized. Polymerizations of the bifunctional maleimide monomers were carried out using a radical initiator at 55°C and the results were compared with those obtained by self-polymerization in the absence of ini-tors. All of the polymers obtained were insoluble in organic solvents owing to cross-linking between different functional groups. The reactivity for homopolymerization of monomer 3 is higher than that of monomers 1 and 2 because the styryl moiety of monomer 3 has better electron-donor strength than the methacrylate moiety. Under the same conditions, GMAPMI was copolymerized with N-vinyl-2-pyrrolidone and styrene as an electron-donor to give higher conversions by electron-donor/acceptor polymerization in which the maleimide moiety of GMAPMI mainly involved as an electron acceptor.     

卟啉-噁二唑二元体系光诱导能量及电子传递研究

以5-对氨基苯基-10,15,20-三苯基卟啉及2-苯基-5-(对氨基苯基)-1,3,4-噁二唑为原料合成了系列卟啉-噁二唑二元化合物, 其结构通过¹H NMR, ESI-MS, IR, UV-Vis确定. 对合成化合物进行光谱性能测定, 结果表明, 在卟啉与噁二唑混合体系中, 存在着卟啉激发态分子向噁二唑基态分子的分子间电子传递过程, 导致卟啉激发态的荧光猝灭; 在卟啉-噁二唑二元体系中, 315 nm激发下发生了由激发态噁二唑基团至卟啉基团的能量传递, 导致噁二唑基团荧光猝灭, 卟啉基团荧光增强. 420 nm激发下不存在分子内卟啉基团向噁二唑基团的电子回传竞争; 电化学性能测定进一步表明从噁二唑基团向卟啉基团的电子传递是可能的. 因此卟啉-噁二唑二元化合物可能作为一种模型, 模拟光合作用中电子给体至叶绿素之间的电子传递过程.     

Design,synthesis, and toward a side-ring optimization of tricyclic thieno[2,3-d]pyrimidin-4(3H)-ones and their effect on melanin synthesis in murine B16 cells

Abstract

Herein, we report the synthesis of 48 novel 3-sulfonylamides containing a tricyclic thieno[2,3-d]pyrimidin-4(3H)-one moiety, and their influence on melanin synthesis in murine B16 cells. All target sulfonylamides were synthesized through key intermediate 3-nitro-thieno[2,3-d]pyrimidin-4(3H)-ones using three types of ipso-nitration reactions. In this case, we converted the pyrido[1,2-a]- fragment of the thieno[2,3-d]pyrimidine moiety to pyrrolo[1,2-a]- and azepino[1,2-a]- side-rings in order to evaluate the bioactivities of the synthesized derivatives for a structure activity-relationships point of view. The obtained results suggest that some of the selected compounds revealed a promising influence on melanin synthesis in murine B16 cells and may serve as lead compounds for further drug discovery and development.     

(1-1)-Linked C-Disaccharides – Synthesis of Bis(β-D-Galactopyranosyl)Methane

ABSTRACT

Bis[C-(galactal-1-yl)]carbinol derivative 2, which is readily obtained by transformation of galactal into a vinyl carbanion and then reaction with a C₁-electrophile, was transformed into the title compound (1b). The procedure required first temporary protection of the carbinol hydroxy group and subsequent transformation of the galactal moiety into the galactopyranosyl moiety. Then deoxygenation of the carbinol and final deprotection could be carried out.     

Synthesis and Antibacterial Studies of Some Novel 2-(Coumarin-3-yl)-5-mercapto-1,3,4-oxadiazoles Containing 2,4,6-Trisubstituted s-Triazine Derivatives

A new series of 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazoles based on various aryl thiourea/ureas incorporating a 1,3,5-s-triazine moiety is reported. The components of this series have been obtained by the reaction of cyanuric chloride (1) with 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazole (2). The prepared 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4,6-dichloro-s-triazine (3) was subsequently treated with morpholine (4) to form 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4-(morpholino)-6-chloro-s-triazine (5). This was further treated with various substituted aryl urea/thioureas (6a–k/7a–k) to afford the title compounds 8a–k and 9a–k, which were and tested for their antibacterial activity (MIC) against different microorganisms. The structures of the novel synthesized compound have been established on the basis of ¹H NMR and FT-IR data together with elemental analysis.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Aromatic and Chiral Phosphonate-Phosphanes - New Types of Hemilabile Ligands

Abstract

Mixed bidentate ligands gained growing interest in catalytic chemistry. These ligands are able to form hemilabile complexes, in which the phosphane group is strongly bonded to the central atom and the second ligand moiety containing O, N or S is weakly co-ordinated. In view of recent developments in asymmetric carbonylation, introduction of chirality in hemilabile ligands should be a promising approach. Recently, we have published the properties of aliphatic phosphonate-phosphanes and their rhodium complexes as catalysts in carbonylation^1,2. Now we wish to present new types of phosphonate-phosphanes 1,2,4 and 5 where both phosphorus-containing groups are connected with arorhatic rings and/or are part of chiral compounds. For example, when dibromo-binaphthyl was used as starting material, both a chiral mixed bidentate ligand 2 and a monodentate phosphinate 3 were obtained, depending on the synthesis route.     

Microwave-assisted synthesis and anti-inflammatory activity evaluation of some novel α-aminophosphonates

An expeditious green synthetic approach was developed for the synthesis of α-aminophosphonates in good yields through one-pot three component reaction (Kabachnik-Fields reaction) of equimolar quantities of N-(4-amino-2-phenoxy phenyl)methanesulfonamide, diethylphosphite and various aldehydes under conventional as well as microwave irradiation methods. The newly synthesized compounds were characterized by NMR (³¹P, ¹H, and ¹³C), Mass, IR and C, H, N analyses. The synthesized compounds were screened for their anti-inflammatory activity using rat paw edema method. Most of the compounds from the series showed good anti-inflammatory activity when compared with standard drug. Especially the compounds 5d bearing 4-hydroxy-3-nitrophenyl moiety, 5e bearing 3-bromo-4-fluorophenyl moiety, 5g incorporated with 2,4-dichlorophenyl moiety and 5f containing 4-chlorophenyl moiety exhibiting edema inhibition of 91.01% to 85.39% after 4 h of carrageenan injection while the other compounds displayed inhibition ≥75%.     

Oxidative Recyclization of 4,6,7-Trichloro-5-hydroxy-2-(2-pyrimidylamino)-2,3-dihydrobenzo[b]furan

When 4,6,7-trichloro-5-hydroxy-2-(2-pyrimidylamino)- 2,3-dihydrobenzo[b]furan reacted with phenyliodoso diacetate, an unexpected oxidative recyclization was observed to give 3-(3,5,6-trichloro-1,4-benzoquinon-2-yl)imidazo[1,2-a]pyrimidine. 2-[N-2-(3,5,6-Trichloro-1,4-benzoquinon-2-yl)ethenylamino]pyrimidine is the intermediate product in the conversion.     

A New Two-Step Stereospecific Synthesis of Glycidic Spiroacetals

ABSTRACT

The spiroacetal moiety has received much attention in recent years owing to its occurence in several biologically important natural products.¹ In that field, the antibiotics avermectins,² milbemycins³ and papulacandins⁴ are of particular interest to us because a carbohydrate precursor could be employed for their syntheses.^5-7 other glycidic spiroacetals were obtained by photocarbocyclization of 2-carbophenyl-β-D-glucopyranosides.⁸     

Terretonin M: A new meroterpenoid from the thermophilic Aspergillus terreus TM8 and revision of the absolute configuration of penisimplicins

Terretonin M (1), a new highly oxygenated tetracyclic meroterpenoid, was isolated from the thermophilic fungus Aspergillus terreus TM8 together with 10 known metabolites: terrelumamide A, asterrelenin, 7-prenyl-indolyl-3-carbaldehyde, (3β,5α,6β)-3,5,6-trihydroxy-ergosta-7,22-diene, sitostenone, linoleic acid, ergosterol, uracil, p-hydroxy-benzoic acid, and indole-3-carboxylic acid. The chemical structure of the new compound was elucidated by extensive 1D, 2D NMR, and ESI HR mass measurements, and by comparison with literature data. The absolute configuration of 1 was resolved by analysis of its NOESY spectrum and comparison of its experimental ECD spectrum with DFT calculations. In parallel to this work, revision of the absolute configuration of penisimplicins 3a and 3b is proposed on the basis of their ECD and ORD data. The isolation and taxonomic characterisation of A. terreus TM8 is reported, and the antimicrobial activity of the crude extract and the isolated compounds was studied as well.     

Cleavage of Diethyl Chromonyl α-Aminophosponate with Nitrogen and Carbon Nucleophiles: A Synthetic Approach and Biological Evaluations of a Series of Novel Azoles,Azines, and Azepines Containing α-Aminophosphonate and Phosphonate Groups

A convenient synthetic approach leading to a series of novel substituted azoles, azines, and azepines linked to the α-aminophosphonate moiety was achieved. The methodology depends on ring opening and ring closure (RORC) of the chromone ring of diethyl chromonyl α-aminophosphonate 1 via its reaction with nitrogen nucleophiles such as primary amines and 1,2-, 1,3-, and 1,4-bi-nucleophiles in ethanolic sodium ethoxide. Also, treatment of compound 1 with some acyclic and cyclic active methylene compounds under the same reaction conditions afforded interesting novel isolated and fused pyridine systems bearing phosphonate groups at the α-position. The screening of antimicrobial activity for the synthesized compounds indicates that connection of pyrazole, oxazepine, and benzodiazepine rings with α-aminophosphonate moiety exhibited good antimicrobial effects. Also, evaluation of their antioxidant properties shows that the compounds having 1,5-benzoxazepinyl and 1,5-benzodiazepinyl units in combination with α-aminophosphonic diester moiety are the most powerful antioxidant agents.     

A new diarylheptanoid from Alpinia officinarum promotes the differentiation of 3T3-L1 preadipocytes

A new diarylheptanoid, namely trans-(4R,5S)-epoxy-1,7-diphenyl-3-heptanone (1), and a new natural product, 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-hepta-4E,6E-dien-3-one (2), were obtained from the aqueous extract of Alpinia officinarum Hance, together with three other diarylheptanoids, 5-hydroxy-1,7-diphenyl-3-heptanone (3), 1,7-diphenyl-4E-en-3-heptanone (4) and 5-methoxy-1,7-diphenyl-3-heptanone (5). The structures were characterised mainly by analysing their physical data including IR, NMR and HRMS. This study highlights that the 4,5-epoxy moiety in 1 is rarely seen in diarylheptanoids. In addition, the five isolates were tested for their differentiation activity of 3T3-L1 preadipocytes. The results showed that these compounds could dose-dependently promote adipocyte differentiation without cytotoxicity (IC₅₀ > 100 μM).     

Crystal structural characterization of three chlorosalicylato titanocene compounds

Abstract  Three chlorosalicylato titanocene compounds, namely [(MeCp)₂Ti(O,O′)(OCC₆H₃-5-Cl)]₂ (1), [(MeCp)₂Ti(O,O′)(OCC₆H₂-3,5-Cl₂)] (2) and [(MeCp)₂Ti(O,O′)(OCC₆H-3,5,6-Cl₃)] (3) have been synthesized via the reaction of (MeCp)₂TiCl₂ [MeCp = η⁵-(CH₃)C₅H₄] with the corresponding substituted chlorosalicylic acids in aqueous-organic systems in high yields and characterized by elemental analysis, IR and ¹H NMR spectra. Single-crystal X-ray diffraction analysis shows that geometries at titanium (IV) atoms are distorted tetrahedrons and the exhibited frameworks are constructed through weak interactions, which are H-bonding, π–π stacking and C–H···π interactions. Additional weak interactions, such as Cl···Cl interactions in compound 1, are also present, which help to form and stabilize crystalline materials. It is noticeable that the discriminating framework structures of three compounds due to their weak interactions existing conspicuous changes which result from the number of chlorine atoms on substituted chlorosalicylates. Graphical Abstract  Three to four coordinated chlorosalicylato titanocene compounds, [(MeCp)₂Ti(O,O′)(OCC₆H₃-5-Cl)]₂ (1), [(MeCp)₂Ti(O,O′)(OCC₆H₂-3,5-Cl₂)] (2) and [(MeCp)₂Ti(O,O′)(OCC₆H-3,5,6-Cl₃)] (3) have been synthesized in aqueous-organic system in high yields. Single-crystal X-ray diffraction analysis shows that geometries at titanium (IV) atoms are distorted tetrahedrons and the exhibited frameworks are constructed through weak interactions. The number of chlorine atoms on substituted chlorosalicylates has an effect on their framework structures.      

The influence of varying reaction conditions on the coordination behavior of the phosphonoformate anion

Abstract

In medical and pharmaceutical science phosphonic acids and phosphonates play an important role with regard to their wide application in various drugs as medicines against osteoporosis or antiviral agents. In the course of the investigations on the coordination chemistry of biologically active phosphonates different salts of the phosphonoformate anion were prepared via hydrolysis of corresponding esters under basic conditions. Depending on the reaction and crystallization conditions, different sodium salts with the phosphonoformate moiety were obtained and structurally characterized.     

Fluorinated styrene-based monomers for cyclopolymerizations

The synthesis of versatile fluorine compounds and monomers for conducting polymer research and cyclopolymerizations is presented. Semiprotected 2,3,5,6-tetrafluoroterephthaldehyde 1 could be elaborated through Wittig olefination chemistry, deprotection and reduction to the previously unknown 4-vinyl-2,3,5,6-tetrafluorobenzylalcohol 8 in good yields. Compound 8 can be reacted to form the malonate ester, and then alkylation on the malonate moiety in mild conditions affords difunctional monomer 3. Through sequential esterifications on the malonate moiety, and subsequent alkylation, compound 4, a difunctional monomer for cyclopolymerization bearing one styrene and one perfluoroaryl styrene moiety, has been obtained. Preliminary experiments show that it is possible to cyclopolymerize 4 under free radical conditions.     

X-ray structures and pharmacological activities of lidocaine derivatives

The molecular and crystal structures of the lidocaine analogs 2-(pyrazol-1-yl)-2′-methylacetanilide (1), 2-(3,5-dimethyl-4-iodo-pyrazol-1-yl)-2′-methylacetanilide (2), 2-(3,5-dimethyl-4-iodo-pyrazol-1-yl)-3′-methylacetanilide (3), and 2-(pyrazol-1-yl)-4′-methylacetanilide (4), are reported, with a summary of their pharmacological activities. In this series, the moiety comprising the heterocyclic ring and the amide alkyl linker displays a common conformation. Molecules of 1–4 form identical hydrogen bonded motifs in their crystals, namely linear chains via intermolecular N–H···O=C hydrogen bonding. Moderate anesthetic and anti-arrhythmic potencies recorded for 1–4 relative to lidocaine are countered by their significantly lower toxicities.     

Synthesis of Some New 1,3,2-Oxazaphosphinine, 1,3,2-Diazaphosphinine,Acyclic, and/or Cyclic α-Aminophosphonate Derivatives Containing the Chromone Moiety

The synthesis of some new 1,3,2-oxazaphosphinine 18, 1,3,2-diazaphosphinine 19, acyclic, and cyclic α-aminophosphonate derivatives 3–17 containing the chromone moiety have been achieved via reaction of 3-(phenyliminomethyl)chromone (1), 3-(phenylaminomethylene)-2-hydroxychromanone (4), and/or 3-(phenylamino-methylene)-2-(phenylamino)chromanone (5) with diethyl phosphite, tris(2-chloroethyl)phosphite, and phenylphosphonic dichloride. Structures of the products were verified on the basis of their elemental analyses, IR, ¹H, and ³¹P NMR spectral data.     

新型甲氨蝶呤衍生物的合成

设计合成了新的甲氨蝶呤(methotrexate, MTX)衍生物1～4, 在这些新化合物中, 将MTX分子中10-位对氨基苯甲酰谷氨酸砌块移植到4-位, 同时在6-位引入苯环芳香基以及甲基等基团. 生物活性测试结果显示, 化合物1～4具有与MTX相似的抑制iNOS活性的作用; 相对于MTX, 选测的化合物2和4明显地增强了抑制K-562白血病细胞株生长的活性. 本研究为进行MTX的结构修饰开辟了新途径, 2-氨基-4-[N-(对氨基苯甲酰谷氨酸)-基]-6-取代基蝶啶衍生物可成为潜在的抗肿瘤候选药物被进一步研究.     

Synthesis, characterization, and biological activities of some 3,5,6-trichloropyridine derivatives

Aromatic carboxylic acids on refluxing with 3,5,6-trichloro-2-pyridyloxyacetylhydrazide in POCl3 gave 5-aryl-2-(3,5,6-trichloro-2-pyridyloxymethyl)-1,3,4-oxadiazoles. The hydrazide on treatment with acid chlorides gave diacylhydrazines, whereas with arylsulfonyl chlorides acyl(arylsulfonyl)hydrazines were obtained. The latter two types of compounds were tested for their antibacterial and antifungal activities whereas 1,3,4-oxadiazole derivatives were tested for their herbicidal activity. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 711–717, May, 2006.     

Synthesis of novel azabicyclo derivatives containing a thiazole moiety and their biological activity against pine-wood nematodes

Abstract

To explore a new skeleton with nematicidal activity, a series of novel azabicyclo derivatives containing a thiazole moiety were designed, synthesized and evaluated for their nematicidal activities. The bioassay results against pine-wood nematodes (Bursaphelenchus xylophilus) showed that most of the title compounds displayed nematicidal activity at a concentration of 40?mg/L. Especially, the title compounds2-((8-methyl-8-azabicyclo[3.2.1]octan-3-yl)oxy)-4-(4-chlorophenyl)thiazole (7e), 2-((8-methyl-8-azabicyclo[3.2.1]octan-3-yl)thio)-4-phenylthiazole (10a) and 2-((8-methyl-8-azabicyclo [3.2.1]octan-3-yl)thio)-4-(4-chlorophenyl)thiazole (10e) exhibited more than 90% mortality against Bursaphelenchus xylophilus.