Current Organic Chemistry - Volume 17, Issue 7, 2013

Five structurally related thiophene-based aldehydes, acetone cyanohydrin, a base, a lipase enzyme and isopropenyl acetate have been mixed in one-pot, leading to the dynamic combinatorial resolution of a cyanohydrin library. The process is applied in optimizing synthetic conditions for the cyanohydrin acetate library obtained in terms of reactivity and enantiopurity. Anhydrous Na2CO3 and lipase PS-D (Burkholderia cepacia Read More

The synthesis of poly-β-alanine by a lipase catalyzed polycondensation reaction between β-alanine esters is reported. The effect of different solvents, reaction temperatures and substrate/enzyme concentrations on polymer yield and degree of polymerization (DP) was determined. Also the effect of methyl substituents at the α and β position of β-alanine was studied. Cross-Linked Enzyme Aggregates (CLEA) of Candida an Read More

The application of specific chemical strategies to alter the structure of enzymes in order to improve their catalytic properties in different biotransformations has been a central role in biocatalysis in recent years. Particularly, cycloaddition reactions have represented a successfully methodology for enzyme chemistry because it is chemoselective and extremely rate-accelerated in aqueous media. Some of the most c Read More

Carbohydrates are complex and structurally diverse compounds in nature with key roles in a broad range of life processes including signal transduction, carcinogenesis and immune responses. Many natural products contain oligosaccharides that are vital for their biological activity. Despite ongoing challenges, tremendous progresses have been made in recent years for the synthesis of carbohydrates. The chemical Read More

Enzymatic polymerization shows to be an advantageous approach in polymer chemistry, particularly in the case of obtaining polymers required for biomedical applications, which are intented for human consumption. Enzymes apply procedures that are environmentally friendly involving waste minimization, hazard reduction, the efficient use of energy and the use of renewable sources. This paper reviews selected examples of t Read More

Epoxide hydrolase (EH) is an interesting tool in different processes of organic chemistry. In this review the different available techniques to improve the properties (activity, stability and selectivity) and to enhance the applicability of this enzyme at a large scale will be studied. In particular, the review focuses on immobilization techniques and different examples are presented using different methodologies.

A simple, convenient and efficient three-component coupling (TCC) reaction toward a variety of (E)-2,3'-bi(3H-indol)-3-one oxime derivatives has been developed. This transformation proceeds via an iron (III)-catalyzed tandem coupling reaction between indoles and sodium nitrite. This methodology provides an alternative approach for easy access of (E)-2,3'-bi(3H-indol)-3-one oximes in good to excellent yields at room t Read More

A screening of nine ionic liquids (ILs) has been carried out in order to study the influence of the ILs anion's and cation's nature and structure on the synthesis of mannosyl myristate catalyzed by Novozym® 435. The best ILs in terms of yield (η) and initial rate (v0) are those based on the TFO- anion. The 24h-yield (24h-η) reached 64.9% in [Bmim][TFO] and 70.9&percnt in [Bmpyrr][TFO] by transesterification while it reached 29. Read More

In this paper, organic thin films of a fluorescent material 5,6-Bis-[4-(naphthalene-1-yl-phenylamino)-phenyl]-pyrazine-2,3- dicarbonitrile (BNPPDC) were prepared by a vacuum deposition method. The typical I-V curve of the film exhibits a favorable roomtemperature bistability. Further recording experiments have been performed with a scanning tunneling microscope, which confirmed that the thin film of the donor-π-acceptor flu Read More