Stereoselective reduction of OF α-alkyl-1,3-diketones and α-alkyl-β-keto esteres catalyzed by 20 isolated, nadph-dependent, ketoreductases

Οι οπτικώς καθαρές α-αλκυλο-β-υδροξυ κετόνες και α-αλκυλο-β-υδροξυ εστέρες είναι αρκετά σημαντικές ενώσεις στην ασύμμετρη οργανική σύνθεση, καθώς έχουν χρησιμοποιηθεί σαν δομικές μονάδες για τη σύνθεση φυσικών προϊόντων και φαρμάκων. Είναι σχετικά μικρού μοριακού βάρους μόρια τα οποία έχουν δυο στερεογονικά κέντρα και περιέχουν τουλάχιστον δυο δραστικές ομάδες (μια υδροξυλομάδα και μια κετονομάδα), ενώ μια τρίτη δραστική ομάδα μπορεί να βρίσκεται μεταξύ των τριών πλευρικών τους υποκαταστατών. Η σύνθεσή τους πραγματοποιήθηκε με στερεοεκλεκτική βιοκαταλυτική αναγωγή των α-αλκυλο-1,3-δικετονών και α-άλκυλο-β-κετο εστέρων, μέσω δυναμικού κινητικού διαχωρισμού, χρησιμοποιώντας είκοσι διαφορετικές, απομονωμένες, NADPH-εξαρτώμενες, κετορεδουκτάσες.Optically active α-alkyl-β-hydroxy ketones and α-alkyl-β-hydroxy esters are important compounds in asymmetric organic synthesis, where they are used as building blocks for synthesis natural products and pharmaceuticals. They are of relatively small molecular weight, bear chirality at two stereogenic centers and contain at least two reactive functionalities (an alcohol, a ketone, and other reactive groups potentially present in the side chain of the substituent). For their synthesis we utilized twenty different isolated NADPH-dependent ketoreductases and the biocatalytic reduction of α-alkyl-1,3-diketones and α-alkyl-β-keto esters, via dynamic kinetic resolution, proved to be a highly efficient method for the preparation of these compounds

First Total Synthesis of Pandamarine

The first total synthesis of pandamarine, an alkaloid isolated from Pandanus amaryllifolius is reported. The key step of this extremely short (six steps in total) and protecting group-free synthesis is a highly efficient cascade reaction sequence initiated by the photooxidation of an easily accessible and symmetric difuran precursor

A Versatile Synthesis of Meyers' Bicyclic Lactams from Furans: Singlet-Oxygen-Initiated Reaction Cascade

All in one: Meyers' bicyclic lactams were synthesized in high yield from furans using a new and powerful method that involves a one-pot singlet-oxygen-initiated reaction cascade. This method has broad synthetic potential because of the ease of access to a wide range of furans with a variety of substituents.This is the pre-peer reviewed version of the following article: Angew. Chem. Int. Ed. 2012, 51, 8868-8871, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/anie.201204419/abstrac

One-Pot Transformation of Simple Furans into Octahydroindole Scaffolds

A highly efficient and general singlet-oxygen-initiated one-pot transformation of readily accessible furans into octahydroindole scaffolds has been developed

Enzymatic Reductions for the Regio- and Stereoselective Synthesis of Hydroxy-keto Esters and Dihydroxy Esters

Ketoreductases were utilized for the stereoselective synthesis of δ-hydroxy-β-keto esters, β-hydroxy-δ-keto esters, and β,δ-dihydroxy esters. Seven out of eight possible stereoisomers were obtained from the enzymatic reduction of the corresponding β,δ-diketo ester in high enantio- and diastereomeric excess