A chiral heterogeneous material was prepared and evaluated as a bifunctional catalyst for the sequential aerobic oxidation-asymmetric intramolecular aza-Friedel–Crafts reaction.

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A two-step process for the transformation of readily available carbohydrate derivatives into acyclic C-nucleosides is described. The carbohydrate undergoes a scission process that is followed by the addition of aryl ketone derivatives, allowing the introduction of a variety of aryl rings. The resulting acyclic C-nucleosides are transformed into 2-deoxy cyclic pyranosides in good yield and excellent stereoselectivity.

A 2‐oxopyrimidinium salt was immobilized onto a polystyrene‐derived polymer to generate a heterogeneous catalyst that effectively promoted the asymmetric Michael addition of glycine‐derived imines to α,β‐unsaturated ketones. The reactions proceeded smoothly to afford the desired adducts, (S)‐tert‐butyl 2‐[(diarylmethylidene)amino]‐5‐oxoalkanoates, in high yields and with high enantioselectivities (up to 92% ee). The polymer catalyst could be recovered and reused at least five times without significant loss of activity or selectivity.

The metal-free, direct conversion of readily available proline derivatives into 2-aryl-3-iodopyrrolidines is carried out under mild conditions and in good yields, using a sequential radical decarboxylation-oxidation-iodination-arylation reaction. These iodinated pyrrolidines are valuable precursors of other compounds. For instance, they can be cyclized to tricyclic compounds or undergo dehalogenation to 2-aryl-2,5-dihydro-1H-pyrroles, which are iminosugar and 2-arylpyrrole precursors. This process provides a short pathway to a variety of alkaloid and drug analogues of potential pharmaceutical interest.

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Simplification of Antitumoral Phenanthroindolizidine Alkaloids: Short Synthesis of Cytotoxic Indolizidinone and Pyrrolidine Analogues. -The synthesis of hydroxyl proline derived indolizidinone and pyrrolidine derivatives bearing aromatic substituents is described. The compounds show cytotoxic activity against human neuroblastoma SHSY-5Y and human breast cancer MCF-7. Best cytotoxic abilities are found for the compounds (VIb) and (VIIb), as well as (VIII) and (IX). -(MIGUELEZ, J.; BOTO*, A.; MARIN, R.; DIAZ, M.; Eur. J. Med. Chem. 66 (2013) 540-554, http://dx.

Synthesis of Indolizidinone Analogues of Cytotoxic Alkaloids: Monocyclic PrecursorsAre also Active. -A two-step route is reported for the transformation of readily available hydroxyproline N-amides into indolizidinone derivatives of type (V) and (VI). The cytotoxic activity of the compounds is studied against the human neuroblastoma SHSY-5Y and human breast cancer MCF-7 cell lines. Especially the derivatives with the bulky biphenyl substituent (Vb) or (VIb) display cytotoxic activities at 30 μM for 48 h. The monocyclic precursors of type (VII) show a comparable or higher cytotoxicity than the bicyclic derivatives. -(BOTO*, A.; MIGUELEZ, J.; MARIN, R.; DIAZ, M.; Bioorg. Med. Chem. Lett. 22 (2012) 10, 3402-3407, http://dx.