Current Organic Chemistry - Volume 14, Issue 17, 2010

Biocatalysis focuses on solving chemical problems using natural catalysts derived from living systems, namely enzymes which were originally evolved for the regulation of the chemistry of life. It has obtained tremendous success in the last three decades for various reasons. These include the systematic use of non natural substances as substrates to perturb enzymes, expanding their range of utility in biocatalysis, breakthr Read More

Naturally occurring enzymes are truly remarkable catalysts. However, many are not suitable for practical synthetic chemistry because of poor substrate or product selectivity. This review highlights recent advances in engineering enzymes for selective catalysis. Selected topics include altering substrate specificity, altering substrate and product selectivity, engineering enzymes that catalyze carboncarbon bond formatio Read More

There is increasing interest in the use of biocatalysts in synthetic applications due to their ability to achieve highly stereoselective and atom efficient conversions. Recent developments in molecular biology techniques and synthetic biology have also enhanced potential applications using non-natural substrates. Here we review strategies to α, α '-dihydroxy ketones and 2-amino-1,3-diols via the use of transketolase, a carbon-ca Read More

Enzymes as biocatalysts offer several advantages over their chemical counterparts, and as such have attracted much attention for use in the synthesis of various organic compounds. However, despite many successes in the practical application of enzymes, the extensive use of enzymes in the synthesis of organic compounds is still hindered by inadequacy in substrate specificity, catalytic activity, enantio-selectivity and stabil Read More

The annotation of the sequences that encode enzymes to their functions is a significant step towards better understanding of the world's biological systems. This is precisely the body of knowledge that Biocatalysis has been building throughout the 20th century on a case-by-case basis. Candidate technologies and methodologies to accomplish this goal are largely available, yet they have not been brought into practice fo Read More

The amino functionality gives important biological activity in pharmaceutical compounds. The formation of chiral amines and amino acids can be accomplished by several chemical routes but enzymatic formation of amines offers many advantages in preparing chiral amino compounds or amination of fragile compounds compared to stoichiometric or catalytic chemical transformations. Biocatalytic routes to amines primari Read More

The knowledge about these Baeyer-Villiger monooxygenases has grown tremendously since the first discovery and fundamental progress in the understanding of structure, function, substrate specificities and other enzyme properties has been facilitated by the development of recombinant biocatalysts. Nature uses these biocatalysts in aerobic biodegradation pathways of cyclic and acyclic ketones and in the biosynthetic pat Read More

Enzymatic promiscuity, namely the possibility that one active site of an enzyme can catalyze several different chemical transformations, has been an important research field and valuable synthesis tool for protein engineering and synthetic chemistry. This review will focus on promiscuous enzyme-mediated reactions that are useful in organic synthesis. Examples include promiscuous hydrolysis reactions, Michael addition, M Read More

Efforts have been made to understand the underlying mechanism and stereochemistry for the observed enantio- and diastereoselectivities in various chiral amine catalyzed Mannich reactions with special reference to proline and its analogous derivatives. Substrate scope in Mannich reaction tunable by structural modification in acceptor and donor components, recent examples, developments, and applications are discussed.

A broad range of free radical transformations such as hydrogen atom transfer, halogen atom transfer, radical cascade, deoxygenations, and additions to olefins and alkynes have been investigated in the presence of InCl3/coreductant (Bu3SnH, TMS3SiH, H3PO2 or NaBH4) as an efficient hydrogen donor system in water. Reactions proceeded smoothly and in excellent yields, with InCl3 playing a dual role as efficient initiato Read More

Reaction of N-methyl/isopropylacetonitrilium hexachloroantimonate 1a, b with N-formylbenzotriazole 2 afforded the corresponding iminium salts 4a, b; of which 4a reacts with the oxime derivatives 5a-d to give the corresponding N-oxyiminium salts 6a-d in a good yield (60-92 %). Reaction of N-methylacetonitrilium hexachloroantimonate 1a with norbornene (7) furnished the new ring system 1,4,4a,5,6,7,8,8a-octahydro-5,8-m Read More