Synthesis of [18F]FDG with alkaline hydrolysis on a low polarity solid phase support.

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

Synthesis of [Gamma-32p]Thiamine Triphosphate

in Analytical Biochemistry (1988), 169(2), 274-278

We developed a novel chemical synthesis of thiamine triphosphate which allows us to incorporate 32P in the gamma position. The reaction is based on the condensation of [32P]orthophosphoric acid and ... [more ▼]

We developed a novel chemical synthesis of thiamine triphosphate which allows us to incorporate 32P in the gamma position. The reaction is based on the condensation of [32P]orthophosphoric acid and thiamine diphosphate in the presence of ethyl chloroformate. After purification by two ion-exchange purification steps, the thiamine derivative has a specific radioactivity of 10 Ci/mmol. The average final yield synthesis is about 10%. [less ▲]

Synthesis of a series of 4H-1,2,4-pyridothiadiazine 1,1-dioxides and their evaluation as new potassium channel openers

Conference (1994, March)

Synthesis of a simplified bryostatin C-ring analogue that binds to the CRD2 of human PKC-alpha and construction of a novel BC-analogue by an unusual Julia olefination process

in Organic Letters (2003), 5(4), 499-502

[GRAPHICS] The synthesis of two truncated bryostatin analogues 2 and 3 is described. High-field NMR measurements on the C-ring analogue 3 in (CH3CN)-H-2 containing 25% (H2O)-H-2 have shown that it binds ... [more ▼]

[GRAPHICS] The synthesis of two truncated bryostatin analogues 2 and 3 is described. High-field NMR measurements on the C-ring analogue 3 in (CH3CN)-H-2 containing 25% (H2O)-H-2 have shown that it binds to the CRD2 of human PKC-alpha at virtually the same position as phorbol-13-acetate (PA) and bryostatin 1 (1). NMR titration studies have also revealed that 3 binds to the CRD2 with a potency similar in magnitude to PA but much less potently than 1. [less ▲]

Synthesis of adherent hydrophilic polypyrrole coatings onto (semi)conducting surfaces

in Chemistry of Materials (2007), 19(9), 2364-2371

Hydrophilic and adherent polypyrrole coatings were prepared by a two-step electrochemical method. First, alpha-pyrrole, omega-acrylate polyethylene oxide (Py-PEO-A) dual macromonomer was synthesized by ... [more ▼]

Hydrophilic and adherent polypyrrole coatings were prepared by a two-step electrochemical method. First, alpha-pyrrole, omega-acrylate polyethylene oxide (Py-PEO-A) dual macromonomer was synthesized by anionic polymerization and electrografted onto (semi)conducting substrates by cathodic polymerization of the acrylic end-group. The obtained adherent coating is hydrophilic and thus swells in water and bears a pyrrole ring, a precursor of the conducting polymer. In a second step, the coating is anodically polarized in a mixture of Py and Py-PEO to give the hydrophilic and adherent polypyrrole. Properties such as morphology, adherence, electroactivity, and hydrophilicity of these coatings were investigated by conventional methods and compared to those of pure polypyrrole coatings. These novel coatings exhibit efficient protein adsorption repellency and are thus good candidates for applications in biomaterials and biosensors. [less ▲]

Synthesis of amonabactins by Aeromonas hydrophila : implication of NRPS of a unique iterate-alternative type

Poster (2011)

Synthesis of amphiphilic copolymers of poly(ethylene oxide) and poly(epsilon-caprolactone) with different architectures, and their role in the preparation of stealthy nanoparticles

in Advanced Functional Materials (2006), 16(11), 1506-1514

Well-defined copolymers of biocompatible poly(epsilon-caprolactone) (PCL) and poly(ethylene oxide) (PEO) are synthesized by two methods. Graft copolymers with a gradient structure are prepared by ring ... [more ▼]

Well-defined copolymers of biocompatible poly(epsilon-caprolactone) (PCL) and poly(ethylene oxide) (PEO) are synthesized by two methods. Graft copolymers with a gradient structure are prepared by ring-opening copolymerization of epsilon-caprolactone (FCL) with a PEO macromonomer of the epsilon CL-type. The epsilon CL polymerization is initiated by a PEO macroinitiator to prepare diblock copolymers. These amphiphilic copolymers are used as stabilizers for biodegradable poly(DL-lactide) (PLA) nanoparticles prepared by a nanoprecipitation technique. The effect of the copolymer characteristic features (architecture, composition, and amount) on the nanoparticle formation and structure is investigated. The average size, size distribution, and stability of aqueous suspensions of the nanoparticles is measured by dynamic light scattering. For comparison, an amphiphilic random copolymer, poly(methyl methacrylate-co-methacrylic acid) (P(MMA-co-MA)), is synthesized. The stealthiness of the nanoparticles is analyzed in relation to the copolymer used as stabilizer. For this purpose, the activation of the complement system by nanoparticles is investigated in vitro using human serum. This activation is much less important whenever the nanoparticles are stabilized by a PEO-containing copolymer rather than by the P(MMA-co-MA) amphiphile. The graft copolymers with a gradient structure and the diblock copolymers with similar macromolecular characteristics (molecular weight and hydrophilicity) are compared on the basis of their capacity to coat PLA nanoparticles and to make them stealthy. [less ▲]

Synthesis of an universal linker to label oligonucleotides via Click Chemistry

Poster (2009, January 21)

For more than 3 decades, oligonucleotides have been used for therapies, imaging and diagnostics. They are known to hybridize specifically with RNA of a complementary sequence on tissue sections and more ... [more ▼]

For more than 3 decades, oligonucleotides have been used for therapies, imaging and diagnostics. They are known to hybridize specifically with RNA of a complementary sequence on tissue sections and more recently to block the expression of target mRNA when administered in vivo (1). Positron emission Tomography (PET) is a sensitive and non invasive imaging technique, and is the most advanced technology currently available for studying in vivo molecular interactions and therapeutic agents. It is a method of choice to assess the pharmacokinetics of new therapeutics agents such as modified oligonucleotides. Among positron-emitting nuclides, fluorine-18 (t1/2 = 109.8 min) appears to be the best candidate due to its favourable physical and nuclear properties. Several of the methods described in the literature to label oligonucleotides present a number of disadvantages (time of synthesis, low overall radiolabelling yield, non-universal). Due to the speed, selectiveness and the relatively mild experimentals conditions, “Click” chemistry seems a powerful technique. The most explored Click reaction is Huisgen 1,3 dipolar cycloaddition. In our case, this reaction occurs between an alkyne group presents on the oligonucleotide and an azide group on the 18F labelled prosthetic group. The originality of our strategy is the use of a universal linker diverted from the trans-4-hydroxy-proline directly connected to the oligonucleotide. This linker mimics a sugar of the oligonucleotide sequence and should improve their resistance to exonucleases. Synthesis of this compound will be presented. [less ▲]

Synthesis of asymmetric telechelic polymers bearing a primary amino end-group

in Journal of Polymer Science. Part A, Polymer Chemistry (2006), 44(10), 3400-3405

Synthesis of basement membrane components by differentiated thyroid cells.

in Biochimica et Biophysica Acta (1985), 846(2), 257-64

Morphological studies indicate that basement membrane formation or maintenance can be achieved in cultures of thyroid cells. In the present investigation we have studied the biosynthesis of this ... [more ▼]

Morphological studies indicate that basement membrane formation or maintenance can be achieved in cultures of thyroid cells. In the present investigation we have studied the biosynthesis of this extracellular matrix by differentiated porcine thyroid cells in culture. They were prepared by two procedures: (1) thyroid cells isolated by dispase digestion of the thyroid gland were maintained in serum-free medium on poly(L-lysine) coated dishes; (2) thyroid follicles released by collagenase treatment of the gland were isolated by differential filtration and cultured in suspension on agarose-coated dishes. In both cases, functional follicular-like structures were obtained as shown by their ability to organify Na125I and to respond to thyrotropin stimulation (250 microU/ml). After incubating the cells with radiolabeled proline or methionine, collagen synthesis was observed with the two types of culture, as shown by the formation of radioactive hydroxyproline and by the synthesis of peptides with electrophoretic properties identical to those of authentic collagen molecules and susceptible to collagenase. Besides variable amounts of type I and type III collagen-like peptides, significant proportions of labeled peptides migrated with type IV collagen chains and were precipitated by anti-type IV collagen antibody; thyrotropin had no significant effect either on the total collagen synthesis or on the relative amounts of the different collagen peptides. When thyroid cells were incubated with [35S]sulfate, a labeled glycosaminoglycan with chromatographic properties analogous to that of heparan sulfate could be obtained in both culture conditions; here again, no effect of thyrotropin was observed. The ability of differentiated porcine thyroid cells to synthesize basement membrane was suggested by their production of type IV collagen and heparan sulfate, two of its potential components. Thyrotropin, which drastically enhanced the functional property of the cells, did not seem to regulate this synthesis. [less ▲]