A new synthetic approach to the lactol moiety of halichoblelide

A stereoselective approach to the γ-lactol moiety of halichoblelide is described starting from commercially available (R)-1-butyn-3-ol. The key step is the hydroboration of a chiral protected 1,2-butadien-3-ol and its addition to furfural

Stereoselective Acetate Aldol Reactions From Metal Enolates

This review deals with metal enolate-mediated stereoselective acetate aldol reactions. It summarizes recent advances on aldol additions of unsubstituted metal enolates from chiral auxiliaries, stoichiometric and catalytic Lewis acids, or acting in substrate- controlled reactions, which provide stereocontrolled aldol transformations that allow the efficient synthesis of structurally complex natural products

Inhibitors of lipogenic enzymes as a potential therapy against cancer

Cancer cells rely on several metabolic pathways such as lipid metabolism to meet the increase in energy demand, cell division, and growth and successfully adapt to challenging environments. Fatty acid synthesis is therefore commonly enhanced in many cancer cell lines. Thus, relevant efforts are being made by the scientific community to inhibit the enzymes involved in lipid metabolism to disrupt cancer cell proliferation. We review the rapidly expanding body of inhibitors that target lipid metabolism, their side effects, and current status in clinical trials as potential therapeutic approaches against cancer. We focus on their molecular, biochemical and structural properties, selectivity and effectiveness and discuss their potential role as antitumor drugs. Keywords: cancer drugs; lipid metabolism; lipogenic enzyme inhibitors

A novel nucleophilic approach to 1-alkyladenosines. A two-step synthesis of [1-N-15] adenosine from inosine

A novel ANRORC mechanism in the reaction of 1-(2,4-dinitrobenzenesulfonyl)inosines with amines has allowed the preparation of 1-alkyladenosines and [1-15N]adenosines in a straightforward way from inosines

Stereodivergent addition of 4-Silyloxy-1,2-Allenes to aldehydes by hydroboration

We have established a new stereodivergent approach to 2-vinyl-1,3-diols based on a hydroboration of allene/addition of aldehyde tandem process. The stereocenter present next to the allenyl moiety (C1) in the starting allene effectively determines the configuration of the new formed carbinol (C3) whereas the relative configuration of C2 and C3 is determined by the configuration (E/Z) of the transient 2- alkenylborane intermediate. It should be noted that the order of mixing of the reagents and the kind of aldehyde used allowed us to obtain three out of the four possible diastereomers of the 1,3- diol

A Useful allene for the stereoselective synthesis of protected quaternary 2-amino-2-vinyl-1,3-diols

Treatment of readily available allene 1 with Cy2BH followed by addition of an aldehyde led to quaternary protected 2-amino-2-vinyl-1,3-diols in high yield and excellent stereochemical purity. The choice of benzoyl as N-protecting group is critical since the observed N- to O-Bz transfer during the process prevents later undesired isomerizations in the adducts and keeps all heteroatoms protected

A new nanomedicine platform to deliver a carnitine palmitoyl-transferase 1 (CPT1) inhibitor into glioma cells and neurons

Obesity and glioblastoma multiforme (GB) are two unmet medical needs where effective therapies are lacking. Carnitine palmitoyl transferase 1 (CPT1), an enzyme catalyzing the rate-lim- iting step in fatty acid oxidation (FAO), is a viable target for both diseases. C75, a fatty acid synthase (FAS) inhibitor, forms an adduct with coenzyme A (CoA) to form C75-CoA, which is a strong com- petitive inhibitor to CPT1 that is selective in its target. However, it is polar and charged, having low cell membrane permeability, and therefore needing a delivery system for intracellular transport. (±)-C75-CoA and its enantio-separated forms (+)- and (−)-C75-CoA were used to form poly-ion com- plex (PIC) micelles with the cationic block co-polymer PEG-PAsp(DET). The drug and polymer were mixed in a 1:1 anion/cation ratio to give 50-70 nm micelles with a unimodal size profile and narrow polydispersity. Size was maintained upon introduction of physiological saline. Micellar (±)-, (+)-, and (−)-C75-CoA were all significantly more cytotoxic compared to the respective free drugs in U87MG. We examined whether C75-CoA inhibits FAO by measuring ATP concentrations in U87MG and GT1-7. ATP generation was found to be hampered after adding C75-CoA in both cell types, with micelle-treated cells producing significantly lower ATP than those treated with free drug, suggesting that the effective intracellular delivery of C75-CoA leads to a more pronounced FAO inhibition. A fluorescent CoA derivative, Fluor-CoA, also yielded monodisperse micelles sim- ilar to C75-CoA. Micellar internalization was significantly greater than that of the free dye. Uptake of both increased with time, with this effect is more pronounced in U87MG than GT1-7. The %Fluor- CoA+ cells were also expressively higher for the micelle across cell lines. From this data, it can be convincingly concluded that neuronal and glioma cellular uptake of micelles is superior to that of the free dye, validating the need for cellular delivery systems for anionic, CoA-type molecules. The micellar form neutralized the negative charge of the cargo, promoting transport into the cell. These outcomes strongly support the effectiveness of using a PIC micelle-type system to deliver anionic small molecules into glioma cells and neurons meant to inhibit enzymes such as CPT1, for future applications in diseases like obesity and cancer

Total synthesis of entecavir

Entecavir (BMS-200475) was synthesized from 4-trimethylsilyl-3-butyn-2-one and acrolein. The key features of its preparation are: (i) a stereoselective boron-aldol reaction to afford the acyclic carbon skeleton of the methylenecylopentane moiety; (ii) its cyclization by a Cp2TiCl-catalyzed intramolecular radical addition of an epoxide to an alkyne; and (iii) the coupling with a purine derivative by a Mitsunobu reaction

Preparation of substituted tetrahydroisoquinolines by Pd(II)-catalyzed NH2-directed insertion of Michael acceptors into C-H bonds followed by NH2-conjugated additions

3,3-Disubstituted tetrahydroisoquinolines are prepared in one step from Michael acceptors and 2-phenylethylamines under Pd catalysis and Ag2CO3 as an oxidant. Presumably, activation of an ortho C-H bond of the aromatic ring with Pd(II) is directed by the primary amine to form a palladacycle. Insertion of the olefin, subsequent conjugated addition of the amine, and reductive elimination of Pd(0) affords the expected products. Silver carbonate is not necessary when 2-phenylethylamines are converted previously to N-benzoyloxy-2-phenylethylamines

Universitat i empresa química: un diàleg necessari entre dos mons complementaris

Un diàleg fluid entre les universitats i altres centres de recerca de Catalunya amb el teixit empresarial és, avui dia, una exigència social ineludible. La transferència de coneixement des dels centres de recerca públics a les nostres empreses ha de servir per millorar la seva competitivitat internacional. Entre les diferents formes de col·laboració, han pres força recentment els doctorats industrials. En aquest article es recullen les característiques bàsiques d'aquests doctorats, així com les experièn- cies del nostre grup de treball i, en concret, el desenvolupament d'una nova síntesi industrial de l'entecavir, un potent fàrmac contra l'hepatitis B