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Lei Bo - - 2010
Sol-gel-derived bioactive glasses (BGs) have been developed for bone tissue regeneration. To develop more reliable bone tissue repair systems, it is necessary to control the morphology and surface textures of bioactive glasses. In this study, we prepared bioactive glasses by sol-gel technology using hydrochloride acid, lactic acid, citric acid and ...
Schmeda-Hirschmann Guillermo - - 2011
Semisynthetic aromatic amides from ARAUCARIA ARAUCANA diterpene acids have been shown to display a relevant gastroprotective effect with low cytotoxicity. The aim of this work was to assess the gastroprotective effect of amino acid amides from imbricatolic acid and its 8 (9)-en isomer in the ethanol/HCl-induced gastric lesions model in ...
Barton Allan F M - - 2010
Essential oils and their constituents have potential as ecologically acceptable pesticides that may also have novel modes of action. In this work hydroxy and ester derivatives of the naturally occurring monoterpenoids 1,8-cineole 3, the main component in most eucalyptus oils, and 1,4-cineole 4 were prepared and their pre-emergence herbicidal activity ...
Liu Hai-Lin - - 2010
The BINOL-amino alcohol compound (S)-4 was found to conduct enantioselective fluorescent recognition of a serine derivative with an unprecedented high ef [enantioselective fluorescent enhancement = (I(D) - I(0))/(I(L) - I(0))] of 12.5. Both (S)-4 and (S)-5 are also found to be highly enantioselective fluorescent sensors for a number of other ...
Su Yi - - 2010
In this paper we report the first synthesis of novel polysialic acid derivatives which is initiated by treatment of polysialic acid with EDC-HCl to yield the inter-residual delta-lactone. Subsequent reaction with amines or hydrazine gives the corresponding polysialic acid amides and hydrazide. Alkylation of the tetrabutylammonium salt of polysialic acid ...
Hargrave Jonathan D - - 2010
The rhodium-catalysed conjugate addition of arylboronic acids to an enantiopure acceptor derived from (R)-S-methylcysteine proceeds under substrate control to provide a range of functionalised phenylalanine derivatives with excellent stereocontrol via a highly diastereoselective protonation.
Nakahira Atsushi - - 2010
In this study, the effect of post acid treatments with HCl aqueous solutions after the hydrothermal process on the microstructure of TiO2-derived titanate nanotube was investigated. Especially, the relationship between local structural changes with the HCl treatment and their thermal stability were investigated by X-ray absorption fine structure (XAFS). Consequently, ...
Kommera Harish - - 2010
A series of novel betulinic acid derivatives 3-11 and betulin derivatives 12-17 were synthesized. The compounds were characterized by the means of (1)H- and (13)C-NMR spectroscopy as well as mass spectrometry. The compounds have been tested on ten tumor cell lines of different histogenic origin. The most active derivatives, containing ...
Palacios Francisco - - 2010
Efficient synthesis of alpha-aminophosphonic acid derivatives is achieved, the key step being a diastereoselective hydrophosphonylation of N-diphenylphosphinyl imines using a readily available chiral cyclic (R,R)-TADDOL-phosphite derived from inexpensive natural tartaric acid.
Chhikara Bhupender S - - 2010
Cytarabine is a chemotherapeutic agent predominately used for the treatment of acute myeloid leukemia and lymphoblastic leukemia. Cytarabine is a polar nucleoside, has a short plasma half-life, and its use is associated with severe side effects. Fatty acyl derivatives of cytarabine were synthesized with the expectation to improve cellular uptake ...
Wada Akimori - - 2010
Synthetic retinoids have generated in the fields of dermatology and oncology due to their potent anti-proliferative and differentiation activities. We efficiently synthesized different demethyl geranylgeranoic acid (GGA) analogs, and evaluated their biological activities. Among the demethyl analogs synthesized, 3-demethyl derivative exhibited the highest anti-proliferative activity in HL-60 cells. In addition, ...
Strom T Amanda - - 2010
Two new fullerene amino acids have been prepared by dipolar addition to C(60) of either the Boc- or Fmoc-Nalpha-protected azido amino acids derived from phenylalanine and lysine. UV-visible and CV studies indicate the as prepared amino acids are a mixture of 5,6-open (major product) and 6,6-closed (minor product) derivatives that ...
Cuquerella M Consuelo - - 2010
Two cholic acid (ChA) analogues, containing a 4-nitrobenzo-2-oxa-1,3-diazole (NBD) moiety at C-3, were incorporated into ChA aggregates and submitted to fluorescence quenching by the two enantiomers of several tryptophan derivatives. In all cases, a significant stereodifferentiation was observed; the most remarkable effect was found when comparing the 3alpha and the ...
Abdel-Aziz Mohamed - - 2010
A series of pyrazine-2-carboxylic acid hydrazide derivatives were synthesized and screened for their activity against Mycobacterium tuberculosis. The results show that pyrazine-2-carboxylic acid hydrazide-hydrazone derivatives 3a-l were less active than pyrazinamide. In contrast, the N(4)-ethyl-N(1)-pyrazinoyl-thiosemicarbazide 4 showed the highest activity against M. tuberculosis H(37)Rv (IC(90) = 16.87 microg/mL). Details of ...
Pertino Mariano Walter - - 2010
Carnosic acid (1) has been shown to possess gastroprotective activity in vitro and in vivo. However, little is known of the gastroprotective effect or cytotoxicity of carnosic acid gamma-lactone (3). To determine structure-activity relationships, a series of 17 esters of 3 were prepared including aliphatic, aromatic, and heterocyclic derivatives. Also, ...
Iwanaga Atsufumi - - 2010
From the 80% acetone extract of "Cimicifugae Rhizoma" (a mixture of Cimicifuga dahurica and C. heracleifolia used medicinally), seven new fukiic acid derivatives (1-7) and a new phenylethanoid derivative (8) were isolated along with eight known compounds (9-16). Fukinolic acid (9) and cimicifugic acids A-J (10-16, 5-7) showed stronger hyaluronidase ...
Li Sheng-Kun - - 2010
A series of 1-acyl-3-isopropenylbenzimidazolone derivatives were synthesized, and their structures were characterized by (1)H and (13)C NMR and elemental analysis. Their fungicidal activities against Botrytis cinerea were also evaluated by spore germination assay. The acrylic acid, methacrylic acid, 4-chlorophenyl acetic acid, and 2-chlorobenzoic acid derivatives exhibited strong fungicidal activity. This ...
Chiou Wen-Hua - - 2010
Facile syntheses of enantiopure trans- and cis-3-hydroxypiperidine derivatives and 3-hydroxypipecolic acids are reported, featuring Rh-catalyzed cyclohydrocarbonylation through common intermediates. A diaxial conformation in a 2,3-disubstituted N-Boc-piperidinyl structure is revealed by an X-ray crystallographic analysis.
Ramapanicker Ramesh - - 2010
Dehydroamino acids are important precursors for the synthesis of a number of unnatural amino acids and are structural components in many biologically active peptide derivatives. However, efficient synthetic procedures for their production in large amounts and without side reactions are limited. We report here an improved procedure for the synthesis ...
Liu Wei - - 2010
The hydroxypropylated psyllium derivatives were successfully prepared with propylene oxide under the alkaline condition for the first time. Four hydroxypropylated psyllium derivatives, denoted as HP1, HP2, HP3, and HP4, were characterized for their hydroxypropyl content, molar substitution, and IR spectra. The hydroxypropyl derivatives were also evaluated for their surface structure, ...
Roth Meike - - 2010
Significant (13)C NMR signal enhancement by a factor of 5000 of a barbituric acid derivative (5-methyl-5-propenyl-barbituric acid) via parahydrogen induced polarization is presented. This hyperpolarization is achieved by hydrogenating 5-methyl-5-propargyl-barbituric acid with 98% enriched para-H(2) under elevated temperature and pressure and transferring the initially created (1)H hyperpolarization with an INEPT-derived ...
Nguyen Thanh Binh - - 2010
Amino acid derived nitrones were conveniently synthesized in good-to-excellent yields by condensation of alpha-ketoesters with N-benzylhydroxylamine. The cycloaddition reactions of these nitrones with different alkenes were investigated under thermal solvent-free conditions. Considering conversions, yields, and selectivities, alkyl vinyl ethers have proven to be valuable partners to achieve this transformation, which ...
Pereira Rangel Luciana - - 2010
Overexpression of the Saccharomyces cerevisiae ABC transporter Pdr5p confers resistance to a range of structurally unrelated xenobiotics. This property allows Pdr5p to be used as a target for novel multidrug resistance reversal reagents or chemosensitizers. Herein, we report the effects of gallic acid derivatives with substitutions either on the ester ...
Hirano Junzo - - 2010
A novel fluorescence enhancement-type derivatizing reagent for amino compounds, 6,7-difluoro-1,4-dihydro-1-methyl-4-oxo-3-quinolinecarboxylic acid (FMQC), was developed. FMQC reacts with aliphatic primary amino compounds to afford strong fluorescent derivatives having high photo-and thermo-stabilities. The FMQC derivatives of amino compounds showed 12-159 times higher fluorescence quantum efficiencies than those of FMQC in aqueous and ...
Matsuda Kenta - - 2010
Although X4 tropic SHIVs have been studied extensively, they show distinct infection phenotypes from those of R5 tropic viruses, which play an important role in HIV-1 transmission and pathogenesis. To augment the variety of R5 tropic SHIVs, we generated a new R5 tropic SHIV from the highly pathogenic X4 tropic ...
Kuduk Scott D - - 2010
Replacement of a phenyl ring with N-linked heterocycles in a series of quinolone carboxylic acid M1 positive allosteric modulators was investigated. In particular, a pyrazole derivative exhibited improvements in potency, free fraction, and CNS exposure.
Fleck Christian - - 2010
Two tacrine-ferulic acid hybrids (1 A, 1 B) and three beta-carboline derivatives (BCs; 2A, 2B, 2C) were tested in vivo on 3-month-old female rats as multi-potent anti-Alzheimer drug candidates. In vitro, the two tacrine-ferulic acid hybrids show higher acetylcholinesterase (AChE) inhibitory activity and comparable butyrylcholinesterase (BChE) inhibitory activity compared to ...
Purkayastha Nirupam - - 2010
An unprecedented cascade of reactions after acid-catalyzed hydrolysis of tert-butyl (2S,5S)-2-tert-butyl-5-(2-fluoroallyl)-3-methyl-4-oxoimidazolidine-1-carboxylate 3a leading to pipecolic acid derivative 5 is presented. The vinylfluoro group is shown to be an acetonyl cation equivalent under acidic conditions. Interestingly, vinylchloro and vinylbromo groups do not show such transformation under the same conditions. The pipecolic ...
Parra Andres - - 2010
Some deoxygenation pathways were tested to remove the hydroxyl groups of the natural triterpenes oleanolic acid and maslinic acid to obtain a practical starting material for the semisynthesis of other interesting organic synthons. Different deoxygenation processes were carried out starting from these triterpenic acids or from several derivatives such as ...
Masuda Katsuyoshi - - 2010
Some D-amino acids such as d-tryptophan and D-phenylalanine are well known as naturally-occurring sweeteners. Photoreactive D-phenylalanine derivatives containing trifluoromethyldiazirinyl moiety at 3- or 4-position of phenylalanine, were designed as sweeteners for functional analysis with photoaffinity labeling. The trifluoromethyldiazirinyl D-phenylalanine derivatives were prepared effectively with chemo-enzymatic methods using L-amino acid oxidase ...
Evidente Antonio - - 2009
A strain of Ascochyta agropyrina var. nana was isolated from Elytrigia repens (quack grass), a noxious perennial weed widespread through the cold regions of the northen and southern hemispheres. Papyracillic acid was isolated for the first time from the fungal solid culture and identified using spectroscopic methods, including X-ray diffractometric ...
Almog Joseph - - 2010
In the first part of a comprehensive research project towards more efficient application of nano-technology to fingerprint visualization, we investigated the possibility of more selective binding of gold nanoparticles (NP) to fingerprint material. We synthesized derivatives of ninhydrin and 1,2-indanedione containing loosely bound thiol groups. In particular: thiohemiketals (THK) of ...
Bade Steffen - - 2009
Many bioanalytic and diagnostic procedures rely on labels with which the molecule of interest can be tracked in or discriminated from accompanying like substances. Herein, we describe a new labeling and detection system based on derivatives of 2,4-dichlorophenoxyacetic acid (2,4-D) and anti-2,4-D antibodies. The 2,4-D system is highly sensitive with ...
Dahia Mostefa - - 2009
The methanolic and aqueous extracts of Pituranthos scoparius (Coss. & Dur.) Benth. & Hook. (Apiaceae) have been analyzed and fifteen metabolites were identified: two cinnamic acids (5-O-caffeoyl quinic acid and 5-feruloyl quinic acid), and thirteen known flavonoids (vicenin-2, six quercetin and six isorhamnetin O-glycosylated derivatives). 5-O-caffeoylquinic acid was the main ...
Lipping Lauri - - 2009
The structures and gas-phase acidities (GA) of several CB(11)H(12)H-based carborane acid derivatives (HA) have been calculated with DFT B3LYP method using 6-311+G**, 6-311++G** basis sets. In order to verify the obtained GA values, several systems were also studied at G3(MP2) level of theory. Inserted substituents (CF(3), F, Cl, Br, I, ...
Ueda Chihiro - - 2010
We have examined the potential bactericidal activities of several tetramic acids derived from Pseudomonas autoinducers against Clostridium difficile, a cause of antibiotic-associated pseudomembranous colitis. Clinical isolates of C. difficile (n=4) were incubated in broth with a chemically synthesized Pseudomonas autoinducer and its tetramic acid derivatives. The structure-activity relationship and the ...
Santacruz Ortega Hisila - - 2009
In this work, we report the synthesis of a combinatorial library of 80 derivatives of EDTA amide x-aminenaphthalene-y-sulfonic acid on four different supports with variable length linker. The sensing fluorescence behavior of these materials for transitions metals was studied by packing the beads into a conventional flow-through cell in a ...
Ingavat Nattha - - 2009
A new tyrosine-derived metabolite, aspergillusol A (4), was isolated on a gram scale, together with a methyl ester of 4-hydroxyphenylpyruvic acid oxime (5) and secalonic acid A, from the marine-derived fungus Aspergillus aculeatus CRI323-04. The tetraol in 4 was identified as erythritol by comparison of the 1H NMR spectrum of ...
Li Min - - 2009
Novel room temperature magnetic chiral ionic liquids derived from amino acids were synthesized and their magnetic properties as well as chiral discrimination abilities were investigated.
Beseda Igor - - 2010
The effect of glycyrrhetinic acid (GA) and GA-derivatives towards 11beta-hydroxysteroid dehydrogenase (11beta-HSD) was investigated. Novel compounds with modifications at positions C-3, C-11 and C-29 of the GA skeleton were prepared. Single crystal X-ray diffraction data of selected substances are reported and discussed.
Tran Tuan P - - 2009
Cyclodehydration of amino acid-derived acyl hydrazide amides to the corresponding oxadiazoles was followed by a second dehydration event, smoothly furnishing the novel imidazo[5,1-b][1,3,4]oxadiazole motif .
Gonz?lez Miguel A - - 2010
A series of C18-oxygenated derivatives of dehydroabietic acid were synthesized from commercial abietic acid and evaluated for their cytotoxic, antimycotic, and antiviral activities.
Roberts Jayne F - - 2010
Haloacetic acids (HAA), such as trichloroacetic acid (TCA), are commonly occurring by-products from disinfection and bleaching processes using sodium hypochlorite. Currently, the lowest no observed effect concentration (NOEC) for TCA is reported to be 8.7microgL(-1), which was derived from a toxicity study conducted in 1981 on Chlorella pyrenoidosa. The purity ...
Sai Sudhir V - - 2009
Direct synthesis of condensed triazoles from diverse sulfamidates by ring opening of sulfamidates with sodium azide followed by one-pot propargylation and cycloaddition furnished title compounds. The methodology in general has been demonstrated on diverse sulfamidates derived from amino acids, amino acid derivatives, and carbohydrates to obtain diverse triazole fused scaffolds. ...
Kwitniewski Mateusz - - 2009
Photodynamic therapy (PDT) is used to treat malignant and nonmalignant diseases. It is also used for cosmetological skin treatment. PDT is generally considered to have a low risk of carcinogenicity. However, instances of nonmalignant human tumors turning malignant have been linked to PDT. In this study, we used 5-aminolevulinic (ALA) ...
McNab Hamish - - 2009
Methoxymethylene Meldrum's acid 1 reacts with 5- and 6-membered lactams in refluxing acetonitrile to give the N-substituted products 9-15. If the reactions are continued for extended times, the Meldrum's acid derivatives decompose to provide enamidoesters e.g. 22-24. Flash vacuum pyrolysis of the 5-membered ring products 9-13 provides reasonable yields of ...
Kundu Pintu K - - 2009
Chiral C(2)-symmetric 3,4-bis-silyl-substituted adipic acid derivatives have been synthesised by a Mg/trimethylsilyl chloride-mediated intramolecular reductive coupling of symmetrical disiloxanes of beta-silylacrylic acid N-oxazolidinone derivatives. Efficient and short syntheses of enantiomerically pure enantiomers of 2,6-dioxabicyclo[3.3.0]octane-3,7-dione have been achieved from the bis-silylated adipic acid derivatives using Fleming-Tamao oxidation as the key step.
Sato Chizuru - - 2009
In plants, the mobile signal needed for wound-induced systemic acquired resistance (WSR) has been elusive. The signal compound involved in WSR is supposed to be JA or its derivatives. On the basis of kinetic study of the accumulation of JA or its derivatives, it was discovered that JA, JA-Ile, tuberonic ...
Boga Carla - - 2009
In order to improve the efficacy of doxorubicin (DOXO) in the treatment of hepatocellular carcinomas, the drug was conjugated with lactosaminated human albumin (L-HSA), a hepatotropic drug carrier. Conjugation was performed using the (6-maleimidocaproyl)hydrazone derivative of the drug (DOXO-EMCH). The maleimide group of DOXO-EMCH reacts with the aminoacidic residues of ...
Dangi Bindi - - 2010
17S-HDPAn-6 (17S-hydroxydocosa-4Z,7Z,10Z,13Z,15E-pentaenoic acid) and 10S,17S-HDPAn-6 (10S,17S-dihydroxydocosa-4Z,7Z,11E,13Z,15E-pentaenoic acid) are potent anti-inflammatory resolvins derived from DPAn-6 (docosapentaenoic acid n-6) and are analogous in structure and action to DHA (docosahexaenoic acid)-derived resolvins. These resolvins have proven to be potential drug candidates, albeit with therapeutic profiles that need optimization. The main objectives of this ...
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