The Synthesis and Characterization of Melamine Based and [Fe/CrSalen] or [Fe/CrSalophen] Capped Polimer Schiff Base Complexes

In this study, by using previously reported monomer complexes [(2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenFeIII)], [(2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenCrIII)], [(2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenFeIII)] and [(2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenCrIII)] obtained by Uysal and Uçan (J Inc Phenom Macrocycl Chem, in press), sixteen new polimer Fe(III) and Cr(III) complexes involving tetradentate Schiff bases N,N′-bis (salicylidene)ethylenediamine-(salenH₂) or bis(salicylidene)-o-phenylenediamine-(salophenH₂) with 2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine or 2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine (Uysal and Uçan, J Inc Phenom Macrocycl Chem, in press) and terephthaldehyde or glutaraldehyde have been synthesized and characterized by means of elemental analysis, ¹H N.M.R., FT-IR spectrscopy, MS, thermal analyses and magnetic susceptibility measurements. The complexes have also been characterized as low-spin distorted octahedral Fe(III) and Cr(III) bridged by catechol and/or COO^? groups.     

Novel 1,3,5-Triazinyl Aminobenzenesulfonamides Incorporating Aminoalcohol,Aminochalcone and Aminostilbene Structural Motifs as Potent Anti-VRE Agents,and Carbonic Anhydrases I,II, VII,IX, and XII Inhibitors

A series of 1,3,5-triazinyl aminobenzenesulfonamides substituted by aminoalcohol, aminostilbene, and aminochalcone structural motifs was synthesized as potential human carbonic anhydrase (hCA) inhibitors. The compounds were evaluated on their inhibition of tumor-associated hCA IX and hCA XII, hCA VII isoenzyme present in the brain, and physiologically important hCA I and hCA II. While the test compounds had only a negligible effect on physiologically important isoenzymes, many of the studied compounds significantly affected the hCA IX isoenzyme. Several compounds showed activity against hCA XII; (E)-4-{2-[(4-[(2,3-dihydroxypropyl)amino]-6-[(4-styrylphenyl)amino]-1,3,5-triazin-2-yl)amino]ethyl}benzenesulfonamide (31) and (E)-4-{2-[(4-[(4-hydroxyphenyl)amino]-6-[(4-styrylphenyl)amino]-1,3,5-triazin-2-yl)amino]ethyl}benzenesulfonamide (32) were the most effective inhibitors with K_Is = 4.4 and 5.9 nM, respectively. In addition, the compounds were tested against vancomycin-resistant Enterococcus faecalis (VRE) isolates. (E)-4-[2-({4-[(4-cinnamoylphenyl)amino]-6-[(4-hydroxyphenyl)amino]-1,3,5-triazin-2-yl}amino)ethyl]benzenesulfonamide (21) (MIC = 26.33 µM) and derivative 32 (MIC range 13.80–55.20 µM) demonstrated the highest activity against all tested strains. The most active compounds were evaluated for their cytotoxicity against the Human Colorectal Tumor Cell Line (HCT116 p53 +/+). Only 4,4’-[(6-chloro-1,3,5-triazin-2,4-diyl)bis(iminomethylene)]dibenzenesulfonamide (7) and compound 32 demonstrated an IC₅₀ of ca. 6.5 μM; otherwise, the other selected derivatives did not show toxicity at concentrations up to 50 µM. The molecular modeling and docking of active compounds into various hCA isoenzymes, including bacterial carbonic anhydrase, specifically α-CA present in VRE, was performed to try to outline a possible mechanism of selective anti-VRE activity.     

三嗪型紫外线吸收剂的合成及性能

用格氏试剂偶联法合成了4个有代表性的三嗪型紫外线吸收剂:2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪、2,4-双(2,4-二羟基苯基)-6-苯基-1,3,5-三嗪、2-(2,4-二羟基苯基)-4,6-二苯基-1,3,5-三嗪和2,4,6-三(2,4-二羟基苯基)-1,3,5-三嗪,测定了它们的紫外光谱。其中,2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪在UVB和UVA都有较强吸收,εmax=36000L/(mol.cm)(λmax=313nm),εmax=36333L/(mol.cm)(λmax=344nm),是其中最好的紫外线吸收剂。     

Investigation of NPB Analogs That Target Phosphorylation of BAD-Ser99 in Human Mammary Carcinoma Cells

The design and development of a small molecule named NPB [3-{(4(2,3-dichlorophenyl)piperazin-1-yl}{2-hydroxyphenyl)methyl}-N-cyclopentylbenzamide], which specifically inhibited the phosphorylation of BAD at Ser99 in human carcinoma cells has been previously reported. Herein, the synthesis, characterization, and effect on cancer cell viability of NPB analogs, and the single-crystal X-ray crystallographic studies of an example compound (4r), which was grown via slow-solvent evaporation technique is reported. Screening for loss of viability in mammary carcinoma cells revealed that compounds such as 2[(4(2,3-dichlorophenyl)piperazin-1-yl][naphthalen-1-yl]methyl)phenol (4e), 5[(4(2,3-dichlorophenyl)piperazin-1-yl][2-hydroxyphenyl)methyl)uran-2-carbaldehyde (4f), 3[(2-hydroxyphenyl][4(p-tolyl)piperazin-1-yl)methyl)benzaldehyde (4i), and NPB inhibited the viability of MCF-7 cells with IC₅₀ values of 5.90, 3.11, 7.68, and 6.5 µM, respectively. The loss of cell viability was enhanced by the NPB analogs synthesized by adding newer rings such as naphthalene and furan-2-carbaldehyde in place of N-cyclopentyl-benzamide of NPB. Furthermore, these compounds decreased Ser99 phosphorylation of hBAD. Additional in silico density functional theory calculations suggested possibilities for other analogs of NPB that may be more suitable for further development.     

Lasioderma chemistry sex pheromone of cigarette beetle (Lasioderma serricorne F.)

A chemical study of the sex pheromone of the cigarette beetle was carried out. Seven components were isolated from active fractions of column chromatography of the female extract, and their structures were elucidated by spectroscopic evidence and confirmed by synthesis to be (4S,6S,7S)-4,6-di-methyl-7-hydroxynonan-3-one (serricornin) (I), 2,6-diethyl-3,5-dimethyl-3,4-dihydro-2H-pyran (anhydroserricornin) (II), 4,6-dimethylnonan-3,7-dione (III), 4,6-dimethylnonan-3,7-diol (IV), 4,6-dimethyl-7-hydroxy-4-nonen-3-one (V), (2S,3R)-2,3-dihydro-3,5-dimethyl-2-ethyl-6-(l-methyl-2-oxobutyl)-4H-pyran-4-one (serricorone) (VI) and (2S,3R)-2,3-dihydro-3,5-dimethyl-2-ethyl-6-(1-methyl-2-hydroxybutyl)-4H-pyran-4-one (serricorole) (VII).These structural features suggested that the occurrence of these components might be related to the polyketide biosynthesis. The behavioral bioassay and BAG experiments revealed the biological role of each component in the copulatory behavior of this insect.     

Eindeutige Synthese des 4,7-Dihydro-4-oxo-1 H-pyrazolo[3,4-b]pyridins – Bemerkungen zur „(N?C)-Umlagerung”︁ von (2-Alkoxycarbonyl-vinyl-amino)pyrazolen

Unambiguous Synthesis of 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine — Further Comments on the “(N C)-Rearrangement” of (2-Alkoxycarbonyl-vinyl-amino)pyrazols 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine 1a is synthesized by decarboxylation of 1-benzyl-5-carboxy-4-hydroxy-pyrazolo[3,4-b]pyridine 4b and debenzylation of 1-benzyl-4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridine 1b with sodium in liquid ammonia. The product from 3-amino-pyrazol and methyl propiolate, formerly described as 1a , obviously is the 6-oxo isomer 2a . Use of the parameter δ¹³(CO) for the structural assignment of pyrazolo[3,4-b]pyridones is only permitted, if in the corresponding media mainly the oxo-tautomer is existing. It is again demonstrated that DMSO is often an insufficient medium. Debenzylation of 1b and similar compounds with SeO₂ is only possible, if the α-position of CO is blocked by a substituent. Otherwise diselenids of type 6 are formed. This obviously is a general reaction of cyclic lactames. The cyclisation of (2-alkoxycarbonyl-vinyl-amino)pyrazols 7 in acidic media, and with catalytical amounts of the corresponding amino-pyrazols gives 6,7-dihydro-6-oxo-pyrazolo[3,4-b]pyridines 2 via amino 4-(2-alkoxycarbonyl-vinyl)pyrazols 8 , i.e. via products of an “(N C)-rearrangement”, while by thermal cyclisation of 7 4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridines 1 are formed.     

The Synthesis and Characterization of s-Triazine-Cored and [Fe(III)Salen]-Capped Polymer Complexes

2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride, C₃N₃Cl₃, 1) was used as the starting material. 2-(4-Carboxyphenylamino)-4,6-dichloro-1,3,5-triazine (2) was obtained from the reaction of cyanuric chloride with 4-aminobenzoic acid in the presence of sodium bicarbonate in acetone. A mononuclear complex (4) was obtained by reacting 2 and [FeSalen]₂O (3). A series of polymeric compounds was obtained by reacting 4 with a series of diamines. The polymeric complexes were characterized by elemental analysis, AAS, FT-IR, ¹H NMR, TGA and magnetic susceptibility measurements. The complexes are low-spin, distorted octahedral Fe(III) species that are bridged by carboxylic acids. The [FeSalen]-containing compounds may have the electronic structure t_2g⁵e_g⁰. All the complexes have six coordination and are polymeric.     

A new family of trinuclear Ru(II) polypyridyl complexes acting as pH-induced fluorescence switch

Tripodal ligands 1,3,5-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)methyl}-2,4,6-trimethylbenzene (L¹), 1,1,1-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)methyl}propane (L²), 2,2′,2′′-tris{4-((1,10-phenanthroline-[5,6-d]imidazol-2-yl)phenoxy)ethyl}amine (L³), and corresponding Ru(II) complexes [(bpy)₆L^1–3(Ru^II)₃](PF₆)₆, shortly called (Ru–L^1–3), have been synthesized. UV–vis absorption and fluorescence spectra of these complexes are both strongly dependent on the pH of the buffer solution. These complexes act as pH-induced off–on–off fluorescence switch through protonation and deprotonation of the imidazole-containing ligands.     

Highly efficient and versatile one-pot synthesis of substituted thienylidene compounds

A novel, efficient, and very mild one-pot synthesis of methyl 2-[(Z)-4-aryl-5-morpholino-3-oxo-2,3-dihydrothiophen-2-ylidene]acetate derivatives under kinetic control has been developed. The title compounds were prepared by the reaction of thioacetomorpholides with dimethyl acetylene-dicarboxylate (DMAD) in the presence of K₂CO₃ in a non-polar solvent with excellent yields.     

Synthesis,Characterization and Anti-Breast Cancer Activity of New 4-Aminoantipyrine-Based Heterocycles

4-Aminoantipyrine was utilized as key intermediate for the synthesis of pyrazolone derivatives bearing biologically active moieties. The newly synthesized compounds were characterized by IR, ¹H- and ¹³C-NMR spectral and microanalytical studies. The compounds were screened as anticancer agents against a human tumor breast cancer cell line MCF7, and the results showed that (Z)-4-((3-amino-5-imino-1-phenyl-1H-pyrazol-4(5H)-ylidene)methylamino)-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 5, 3-(4-bromophenyl) -1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 13, 1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1-Hpyrazol- 4-yl)-3-(4-iodophenyl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 14, 3,3′-(4,4′-sulfonylbis(4,1-phenylene))bis(1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol- 4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile) 16, (Z)-1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-hydrazono-4-oxo-3-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 17, (Z)-1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-4-oxo-3-phenyl-2-(2-phenylhydrazono)-1,2,3,4-tetrahydro pyrimidine-5-carbonitrile 18, and (Z)-4-(3-amino-6-hydrazono-7-phenyl-6,7-dihydro pyrazolo[3,4-d]pyrimidin-5-yl)-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 19 were the most active compounds with IC₅₀ values ranging from 30.68 to 60.72 μM compared with Doxorubicin as positive control with the IC₅₀ value 71.8 μM.     

Synthesis and characterization of rare examples of stable potassium and arylcalcium triethylboranate complexes

Stabilization of potassium triethylboranate can be achieved in solution as well as in the solid state with tridentate 1,3,5-trimethyl-1,3,5-triazinane (tmta) as dimeric [(tmta)K(μ-H)BEt₃]₂ (1). The metathesis reaction of the post-Grignard reagent [2,6-(tol)₂C₆H₃-Ca(thf)₃I] (2) with potassium triethylboranate yields an unusual hydrogen bridged organocalcium contact ion pair as hydrocarbon soluble [(thf)(dme)Ca(C₆H₃-2,6-tol₂)HBEt₃] (3) which shows no tendency to dismutate to the homoleptic derivatives.     

Synthesis of Bitopic Ligands as Potent Dopamine D2 Receptor Agonists

In this study, we designed and synthesized twelve bitopic ligands as dopamine D₂ receptor (D₂R) agonists. The forskolin-induced cAMP accumulation assay revealed that all the finial compounds are able to activate D₂R. Furthermore, bitopic ligand N-((trans)-4-(((2,3-dihydro-1H-inden-2-yl)(propyl)amino)methyl)cyclo-hexyl)-1H-pyrrolo[2,3-b]pyridine-2-carboxamide ( 11 b ) showed 21-fold higher potency than lead compound propyl aminoindane ( 2 ) and 17-fold higher subtype selectivity for D₂R over D₄R, indicating that the optimal length of spacer affects the D₂R functionality. Molecular modeling study exhibited that 11 b formed an electrostatic interaction and two H-bonds with amino acid Asp114, which contributes significantly to the D₂R functional activity. Taken together, we discovered a bitopic ligand 11 b as potent D₂R agonist, which may be used as a tool compound for further study.     

A novel synthesis of indeno[2',1': 5,6] pyrido[2,3- d ][1,2,4]triazolo[4,3- a ]pyrimidines

Reaction of 5-(4-chlorophenyl)-2-thioxo-2,3-dihydro-1H-indeno[2',1':5,6] pyrido[2,3-d]pyrimidine-4,6-dione with hydrazonoyl chlorides gave 1,2,4-triazolo[4,3-a]pyrimidine derivatives regioselectively in good yields. The structures of the newly synthesized compounds are established on the basis of chemical and spectroscopic evidence as well as their synthesis by alternative methods.     

Functionalization of polystyrene particles with monochiral epoxy groups: Potent precursors for chiral polyfunctional polymers

Polystyrene particles have been functionalized with monochiral 2,3-epoxypropoxy methyl groups [(S)-1] by an efficient five step reaction sequence involving chloromethylation, coupling with glycerol-2,3-acetonide, hydrolysis of the acetonide groups, monotosylation of the resulting diol and ring closure by base treatment. The polymeric epoxide was reacted with diethyleneglycol monomethyl ether under the influence of BF₃·Et₂O or under basic conditions, and with 1-phenylethylamine using LiClO₄ as a catalyst, affording β-hydroxyether- (2) and amino alcohol-substituted (3) polymers, respectively.     

Ringtransformationen heterocyclischer Verbindungen. XII. Neuartige Spiroindoline via Ringtransformation von 2,4,6-Triaryl-pyryliumsalzen mit 2-Methylen-indolinen

Ring Transformations of Heterocyclic Compounds. XII. Novel Spiroindolines via Ring Transformation of 2,4,6-Triarylpyrylium Salts with 2-Methyleneindolines 2,4,6-Triarylpyrylium salts 1 react with 2-methyleneindolines 2 or their salts 2 HX in the presence of triethylamine/acetic acid in ethanol by a 2,5-[C₄ + C₂] pyrylium ring transformation to give diastereomerically pure 6-aroyl-3,5-diaryl-spiro[cyclohexa-2,4-diene-1,2′-indolines] 3 , which represent a novel type of spiroindoline compounds. When the 1′-phenyl substituted spiroindolines 3 (RPh, R′H) are treated with p-toluenesulfonic acid in chloroform the 4,6-diaryl-2-[1-methyl-1-(2-phenylaminophenyl)methyl]benzophenones 4 are obtained as the result of an intramolecular amine elimination. Structural elucidation of the reaction products 3/4 is based on spectroscopic data and on an X-ray determination of the bis(4-bromophenyl) substituted spiroindoline 3i.     

Electrochemical behavior of a new <Emphasis Type="Italic">s</Emphasis>-triazine-based dendrimer

The electrochemical behavior of a new G-2-s-triazine-based dendrimer, 2,4,6-tris-{4-{4,6-bis-{4-{4,6-bis-[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-s-triazin-2-yl}-piperazin-1-yl}-s-triazine, (I), was studied in dimethylsulfoxide solution by cyclic voltammetry, on platinum and graphite electrodes. The electrochemical properties of I were compared with that of one of its precursor, N-{4,6-bis{4-{4,6-bis[(1S,2S)-1,3-dihydroxy-1-(4-nitrophenyl)-prop-2-ylamino]-s-triazin-2-yl}-piperazin-1-yl}-triazin-2-yl}-piperazine), (II), together with that of the starting material, (1S,2S)-2-amino-1-(4-nitrophenyl)-propane-1,3-diol (“p-nitrophenylserinol”), (III).     

Condensed Tannins: The Formation of a Diarylpropanol-Catechinic Acid Dimer from Base-Catalyzed Reactions of (+)-Catechin

Reaction of (+)-catechin at pH 12 and 40 °c results in the stereoselective (if not stereospecific) formation of an enolic form of 1-[6-(3′,4′-dihydroxyphenyl)-7-hydroxybicyclo[3.3.1]nonane-2,4,9-trione-3-yl] -1-(3,4-dihyroxyphenyl)-3-(2,-4,6-trihydroxyphenyl)-propan-2-ol. The n.m.r. chemical shift assignments determined by a variety of two-dimensional experiments permit a conclusion that the compound is one of four diastereoisomers possible from reaction of the two quinone methide intermediates. Stereoselectivity in the formation of this compound can be accounted for by preference for Re-face attack on both 2-C's of the quinone methides involved in the formation of the molecule.     

A dinuclear copper(II) complex and a zigzag chain iron(II) polymer based on the 4-antipyrine derived Schiff base ligands: The hydroxylation and redox occurred under the solvothermal conditions

A new dinuclear copper(II) compound, [Cu₂(L1-O)₂] (1) (L1 = (4E)-4-(2-hydroxybenzylideneamino)-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one), and zigzag chain polymer, {[FeCl₂(L2)]}_n (2) (L2 = 1,5-dimethyl-2-phenyl-4-{[(1E)-pyridine-4-ylmethylene]amino}-1,2-dihydro-3H-pyrazol-3-one), were synthesized by solvothermal reactions and structurally characterized. The methyl group hydroxylation and the redox have been observed in the preparation of 1 and 2, respectively.     

Biocatalytic synthesis of some chiral pharmaceutical intermediates by lipases

Chiral intermediates were prepared by biocatalytic processes for the chemical synthesis of three pharmaceutical drug candidates. These include (i) the synthesis of [(3R-cis)-3-(acetyloxy)-4-phenyl-2-azetidinone2 for the semi-synthesis of paclitaxel (taxol)5, an anticancer compound; (ii) synthesis of chiral (exo,exo)-7-oxabicyclo [2.2.1] heptane-2,3-dimenthanol monoacetate ester9 for the chemoenzymatic preparation of a thromboxane A₂ antagonist; (iii) the enzymatic synthesis ofS-(−) 3-benzylthio-2-methylpropanoic acid, a key chiral intermediate for the synthesis of antihypertensive drugs captopril10 or zofenopril13.     

Polymerization of Cyclophosphazenes with Spriocyclic Methacrylate Containing Substituents

The radical addition polymerization and copolymerization of the cyclophosphazene monomers with spirocyclic methacrylate containing substituents, spiro(2,3-dioxypropylmethacryloyl)tetrachlorocyclotriphosphazene, N₃P₃Cl₄[OCH₂CH(OC(O)=CH₂)O] (1) and spiro((2-methyl-3-oxy-2-(oxymethyl)propyl)methacryloyl)tetrachlorocyclotriphosphazene, N₃P₃Cl₄[OCH₂CMe(CH₂OC(O)=CH₂)CH₂O] (2), has been investigated. In the case of 1, homopolymerization using AIBN as the initiator yielded only cross-linked solids. Copolymerization of 1 with methyl methacrylate was accomplished using VAZO 52 under milder initiation temperature. GPC of copolymer suggested a significant amount of chain transfer. Homopolymerization of 2 gave low isolated yields of the homopolymer but copolymerization with methyl methacrylate yielded the expected copolymers. The reactive chlorine atoms in the copolymers of 2 can be replaced by trifluoroethoxide or methyl amine. Thermal properties of the copolymers were examined by DSC, TGA and pyrolysis mass spectrometry.