Current Organic Synthesis - Volume 11, Issue 3, 2014

Herein, an overview of the most important developments on the synthesis and reactivity of halogen-containing chromones, namely simple chromones, flavones, styrylchromones, thiochromones and furochromones are reviewed (since 2003).

Carbohydrates have been recognized as privileged structures for the regio- and stereo-controlled appendage of pharmacophores to generate new derivatives with potential application in drug discovery processes. Even though most of the carbohydrate templates have been generated from pyranoses, other sugar derivatives have also been employed in the assembly of such structures. In this review, attention has been direct Read More

Optically active α,β-epoxy derivatives can be converted into many types of useful chiral compounds, such as chiral building blocks and synthetic intermediates for biologically active compounds. The most up-to-date and most economical method for the preparation of enantiomeric pure epoxides is the catalytic asymmetric Darzens condensation. The homogeneous phase and heterogeneus phase (phase-transfer [PT]) cat Read More

Thiol-containing biomolecules, such as cysteine (Cys), homocysteine (Hcy), glutathione (GSH), play crucial roles in maintaining biological systems. For example, elevated levels of Hcy have been implicated as an independent risk factor for tumor invasion and metastasis. Being associated with a wide variety of cancer progressions, there is a significant interest in looking for the fluorescent detection of such thiol species (Cys, Hcy, Read More

This review demonstrates that oximes and their derivatives are valuable starting materials for the preparation of many classes of heterocyclic compounds. The main group of reactions includes the cyclization of unsaturated oxime derivatives. Using these starting materials pyrroles, isoxazoles, pyridines and isoquinolines were prepared. Some heterocyclic systems (for example, seven-membered rings) were obtained Read More

In this review, the methods forming P-C bonds by coupling reactions, utilizing different >P(O)H species, are surveyed systematically. The components of the reactions are organic halides, >P(O)H species comprising dialkyl phosphites, H-phosphinates or secondary phosphine oxides and the catalyst, that is in most cases the complex of palladium or its salts. The Hirao reaction discovered in 1980 is in the focus that is the c Read More

Electrogenerated base induced dehydrocoupling of pyrazol-5-ones was investigated. The results showed that dehydrodimers and dehydrotrimers were generated simultaneously under electrolytic conditions, and their ratio was mainly dependent on the reaction temperature and the nature of the supporting electrolyte. It was observed that the formation of dimer 2 is preferred at lower temperatures and that trimer 3 is prefere Read More

A new series of gem-phosphonate-phosphates bearing N-alkyl groups and aromatic substituents has been prepared by reductive cleavage of the isoxazolidine ring with metal carbonyls, using the gem-phosphonate-phosphate rearrangement.

Methyl ketone derivatives can be accessed from 5-oxo-1-alkynes in an iodine-initiated hydration of the terminal alkynes. Use of molecular iodine in this manner is novel, inexpensive and a greener alternative to the traditional use of transition metal catalysts. Herein, we report the results of a methodology study which sheds light on the underlying mechanism of this new, metal-free reaction. Our findings indicate that the hydra Read More