22102-92-7

An easily handled one-pot synthetic procedure was previously developed for the synthesis of bisphosphinates starting from acyl chlorides. Herein, other trivalent derivatives as acid anhydrides and activated esters were tested to form various bisphosphinates. This modulation of the reactivity can be controlled according to the nature of the acid derivative for the use of sensitive and functionalized substrates.

Lipid metabolism in Mycobacterium tuberculosis (Mtb) relies on 34 fatty acid adenylating enzymes (FadDs) that can be grouped into two classes: fatty acyl-CoA ligases (FACLs) involved in lipid and cholesterol catabolism and long chain fatty acyl-AMP ligases (FAALs) involved in biosynthesis of the numerous essential and virulence-conferring lipids found in Mtb. The precise biochemical roles of many FACLs remain poorly characterized while the functionally non-redundant FAALs are much better understood. Here we describe the systematic investigation of 5′-O-[N-(alkanoyl)sulfamoyl]adenosine (alkanoyl adenosine monosulfamate, alkanoyl-AMS) analogs as potential multitarget FadD inhibitors for their antitubercular activity and biochemical selectivity towards representative FAAL and FACL enzymes. We identified several potent compounds including 12-azidododecanoyl-AMS 28, 11-phenoxyundecanoyl-AMS 32, and nonyloxyacetyl-AMS 36 with minimum inhibitory concentrations (MICs) against M. tuberculosis ranging from 0.098 to 3.13 μM. Compound 32 was notable for its impressive biochemical selectivity against FAAL28 (apparent Ki = 0.7 μM) versus FACL19 (Ki > 100 μM), and uniform activity against a panel of multidrug and extensively drug-resistant TB strains with MICs ranging from 3.13 to 12.5 μM in minimal (GAST) and rich (7H9) media. The SAR analysis provided valuable insights for further optimization of 32 and also identified limitations to overcome.

The present invention describes W-position modified cytidine nucleotides of formula (I). Provided herein are methods of chemical synthesis of ΛΡ-modified cytidine nucleoside triphosphates and their applications as well as uses of the cytidine analogues for the synthesis of modified nucleic acids. The nucleic acid molecule comprises DNA, RNA or a combination of DNA/RNA. One of many applications of modified cytidine nucleotides described herein is enzyme selection, when an enzyme of interest bears an activity of an esterase, amidase, oxidoreductase, lyase, ligase or other enzymatic activity, formula (I) wherein the substituants are as defined in the appended claims.

The aim of this study was to synthesize and characterize fatty acid-grafted-chitosan (fatty acid-g-CS) polymer and their nanomicelles for use as carriers for gene delivery. CS was hydrophobically modified using saturated fatty acids of increasing fatty acyl chain length. Carbodiimide along with N-hydroxysuccinimide was used for coupling carboxyl group of fatty acids with amine groups of CS. Proton nuclear magnetic resonance and Fourier transform infrared spectroscopy were used to quantify fatty acyl substitution onto CS backbone. The molecular weight distribution of the synthesized polymers was determined using size exclusion high performance liquid chromatography and was found to be in range of the parent CS polymer (～50 kDa). The critical micelle concentration (cmc) of the polymers was determined using pyrene as a fluorescent probe. The cmc was found to decrease with an increase in fatty acyl chain length. The amphiphilic fatty acid-g-CS polymers self-assembled in an aqueous environment to form nanomicelles of ～200 nm particle size and slightly positive net charge due to the cationic nature of free primary amino groups on CS molecule. These polymeric nanomicelles exhibited excellent hemo- and cytocompatibility, as evaluated by in vitro hemolysis and MTT cell viability assay, respectively, and showed superior transfection efficiency compared to unmodified chitosan and naked DNA. The surface of these nanomicelles can be further modified with ligands allowing for selective targeting, enhanced cell binding, and internalization. These nanomicelles can thus be exploited as potential nonviral gene delivery vectors for safe and efficient gene therapy.

N-Acetyl glucosamine (GlcNAc) is one of the most abundant biomolecules on Earth and is cheaply available from chitin, a major component of crustaceans. The key step in the conversion of GlcNAc to high-value products is the de-N-acetylation to glucosamine, in itself a valuable dietary supplement that is produced at over 29:000 tons scale per annum by chemical hydrolysis, a process that requires harsh reaction conditions and leads to side products requiring separation. Here, we report for the first time the isolation and characterisation of an enzyme, a deacetylase from Cyclobacterium marinum that is able to catalyse the highly selective quantitative hydrolysis of GlcNAc to glucosamine under mild reaction conditions. This enzyme is small (38 kDa), is easily obtainable by heterologous expression in E. coli, has high turnover rates (kcat=61 s-1), tolerates high substrate concentrations (over 100 g L-1) and can be repeatedly re-used as an immobilised catalyst. When coupled with chitinase, the high selectivity of the enzyme for GlcNAc over other biomolecules allowed one-pot extraction of glucosamine from crude solid mushroom fractions containing chitin, thus allowing for alternative production of glucosamine from non-animal sources, of benefit to consumers with crustacean allergies and vegan diets. We suggest that the deacetylase fills an important gap in the sustainable exploitation of GlcNAc and chitin.

Chemical fractionation of the southern Australian marine sponge Phoriospongia sp. (CMB-03107) yielded phorioadenine A (1) as a nematocidal agent and the first reported example of a 6-N-acyladenine natural product. The structure of 1 was confirmed by spectroscopic analysis and the chemical synthesis of racemic (1a) and enantiomeric (1b) analogues. HPLC-ESIMS analysis of the crude sponge extract with comparisons to the synthetic 6-N-acyladenosine 2a provided evidence that the biosynthetically related adenosine, phorioadenosine A (2), was present as a trace co-metabolite. The rare starfish metabolite asterubine (3) was also isolated as a co-metabolite, and its structure confirmed by spectroscopic analysis and chemical synthesis. Biological investigations confirmed that natural products 1-3 and synthetic analogues 1a-e and 2a were not cytotoxic to multiple mammalian cancer cell lines, or Gram-positive or -negative bacteria. Nematocidal activity (inhibition of larval development of Haemonchus contortus) detected in the Phoriospongia sp. extract was attributed to 1 (LD9931 μg/mL), with preliminary structure-activity relationship investigations confirming the importance of the N-acyl side chain.

A novel series of α-phenyl-N-tert-butyl nitrone derivatives, bearing a hydrophobic chain on the aromatic ring and three hydroxyl functions on the tert-butyl group, was synthesized through a short and convenient synthetic route based on a one-pot reduction/condensation of tris(hydroxymethyl)nitromethane with a benzaldehyde derivative. Because of the presence of hydroxyl functions on the tert-butyl group, an intramolecular Forrester-Hepburn reaction leading to the formation of an oxazolidine-N-oxyl compound was observed by electron paramagnetic resonance (EPR). The mechanism of cyclization was further studied by computational methods showing that intramolecular hydrogen bonding and high positive charge on the nitronyl carbon could facilitate the nucleophilic addition of a hydroxyl group onto the nitronyl carbon. At high nitrone concentrations, a second paramagnetic species, very likely formed by intermolecular nucleophilic addition of two nitrone molecules, was also observed but to a lesser extent. In addition, theoretical data confirmed that the intramolecular reaction is much more favored than the intermolecular one. These nitrones were also found to efficiently trap carbon-centered radicals, but complex spectra were observed due to the presence of oxazolidine-N-oxyl derivatives.

We describe the design, synthesis and biological evaluation of conformationally-locked 5′-acyl sulfamoyl adenosine derivatives as new parasitic inhibitors against Trypanosoma and Leishmania. The conformationally-locked (3′-endo, North-type) nucleosides have been synthesized by covalently attaching a 4′-CH2-O-2′ bridge (Fig. 2) across C2′-C4′ of adenosine in order to reduce the conformational flexibility of the pentose ring. This is designed to decrease the entropic penalty for complex formation with the target protein, which may improve free-energy of stabilization of the complex leading to improved potency. Conformationally-locked 5′-acyl sulfamoyl adenosine derivatives (16-22) were tested against parasitic protozoans for the first time in this work, and showed potent inhibition of Trypanosoma cruzi, Trypanosoma brucei, Trypanosoma rhodesiense and Leishmania infantum with IC50 = 0.25-0.51 μM. In particular, the potent 5′-pentanyl acyl sulfamoyl adenosine derivative 17 (IC50 = 0.25 μM) against intracellular L. infantum amastigotes and Trypanosoma subspecies is interesting in view of its almost insignificant cytotoxicity in murine macrophage host cells (CC50 >4 μM) and in diploid human fibroblasts MRC-5 cell lines (CC50 4 μM). This work also suggests that variable alkyl chain length of the acyl group on the acylsulfamoyl side chain at 5′ can modulate the toxicity of 5′-O-sulfamoylnucleoside analogues. This conformationally-locked sulfamoyl adenosine scaffold presents some interesting possibilities for further drug design and lead optimization.

Sub-100 nm hollow gold nanoparticle superstructures were prepared in a direct one-pot reaction. A gold-binding peptide conjugate, C6-AA- PEPAu (PEPAu = AYSSGAPPMPPF), was constructed and used to direct the simultaneous synthesis and assembly of gold nanoparticles. Transmission electron microscopy and electron tomography revealed that the superstructures are uniform and consist of monodisperse gold nanoparticles arranged into a spherical monolayer shell.

The preparation of a collection of 131 small molecules, reminiscent of families of long chain N-acyl tyrosines, enamides and enol esters that have been isolated from heterologous expression of environmental DNA (eDNA) in Escherichia coli, is reported. The synthetic libraries of N-acyl tyrosines and their 3-keto counterparts were prepared via solid-phase routes, whereas the enamides and enol esters were synthesized in solution-phase.

Comblike, surfactant polymers for changing the surface properties of biomaterials are provided. Such surfactant polymers comprise a polymeric backbone of repeating monomeric units having functional groups for coupling with side chains, a plurality of hydrophobic side chains linked to said backbone via the functional groups, and a plurality of hydrophilic side chains linked to said backbone via the functional groups. The hydrophobic side chains comprise an alkyl group comprising from 2 to 18 methylene groups. The alkyl groups are linked to the polymeric backbone through ester linkages, secondary amine linkages, or, preferably, amide linkages. The hydrophilic side chain is selected from the group consisting of: a neutral oligosaccharide, which, preferably, has weight average molecular weight of less than 7000; a charged oligosaccharide, preferably a negatively charged oligosaccharide having a weight average molecular weight of less than 10,000; an oligopeptide of from about 3 to about 30 amino acid residues, said oligopeptide having an amino acid sequence which interacts with protein receptors on the surface of cells; and combinations thereof. Methods of making the surfactant polymers and using the surfactant polymers to alter the surface properties of a biomaterial are also provided.

Amphiphilic compounds, obtained by grafting aliphatic acids onto a modified cyclodextrin, have been synthesized and studied by solution NMR.The large chain-length dependence of the NMR spectra in aqueous media is explained by the possible formation of auto-inclusion complexes.This process has been evidenced by extensive NMR experiments and by competition with potential guests.This new class of molecules ("lollipops") provides important information for the optimization of a design for amphiphilic transporters to be included in organized phases such as micelles or liposomes.

The synthesis of the acyclic MDP analogs 27-37 is described, the carbohydrate moiety of muramic acid being replaced by acyclic amino alcohol structures.Their preparation was accomplished by hydrolytic cleavage of the cyclic, disubstituted 3-morpholinones

N-mono-substituted derivatives of diamino acids are prepared by the reaction of succinimidyl esters of carboxylic acids or substituted carbonic acids with the unprotected diamino acid. The acylation preferentially occurs at the side chain or terminal amino group of the diamino acid. For example, selective acylation of the terminal amino group of lysine occurs without first having protected the 2-amino group. Such acylation has application in the preparation of inter alia N6 -palmitoyl-lysine.