Up to four stereocenters with a well-defined configuration are generated in a single synthetic step by the cyclocondensation of (R)-phenylglycinol or (1S,2R)-1-amino-2-indanol with stereoisomeric mixtures (racemates, meso forms, diastereoisomers) of cyclohexanone-based δ-keto-acid and δ-keto-diacid derivatives in enantio- and diastereoconvergent processes that involve dynamic kinetic resolution...

Two 5-acyl-2-dimethylaminonaphthalene derivatives, one with a propionyl group and the other with a fused cyclohexanone ring, are investigated as sensors of H-bond-donating ability in protic solvents of low solvent acidity. Their fluorescence is highly quenched in protic solvents, and the quenching order of magnitude is linearly related to the H-bond-donating ability of the solvent as quantified...

A Ser105Ala mutant of the lipase B from Candida antarctica enables 'perhydrolase-only' reactions. At the example of the chemoenzymatic Baeyer-Villiger oxidation of cyclohexanone, we demonstrate that with this mutant selective oxidation can be achieved in deep eutectic solvent while essentially eliminating the undesired hydrolysis reaction of the product.

The dehydrogenation of cyclohexanones affords cyclohexenones or phenols via removal of 1 or 2 equiv of H2, respectively. We recently reported several Pd(II) catalyst systems that effect aerobic dehydrogenation of cyclohexanones with different product selectivities. Pd(DMSO)2(TFA)2 is unique in its high chemoselectivity for the conversion of cyclohexanones to cyclohexenones, without promoting su...

With a washed and dialyzed preparation of rabbit kidney cortex mitochondria, the requirement of Mg ++ (or R/In++), inorganic phosphate, and adenosinetriphosphate for the enzymatic oxidation of a-ketoglutarate to succinate plus COZ may be readily demonstrated (2), confirming results (3) with cat heart muscle. Diphosphothiamine is a necessary coenzyme for this enzymatic system (4, 5). However, in...

In 1942 Wiesner (1) and Waksman, Horning, and Spencer (2) demonstrated that filtrates from cultures of Aspergillus clavatus grown upon synthetic media possess antibiotic activity. These investigators extracted and partially purified the active material (which was named clavacin by Waksman) but did not report its isolation in pure form. As a result of the observations made by Waksman’s group, pa...

Cyclohexanone monooxygenase (CHMO) is a promising biocatalyst for industrial reactions owing to its broad substrate spectrum and excellent regio-, chemo-, and enantioselectivity. However, the low stability of many Baeyer-Villiger monooxygenases is an obstacle for their exploitation in industry. Characterization and crystal structure determination of a robust CHMO from Thermocrispum municipale i...

Flory Fox, Kurata-Stockmayer, Berry, Inagaki-Suzuki-Kurata, Stockmayer-Fixman and Ahmad-Baloch methods based on the excluded volume theory have been applied to poly(vinyl chloride)-cyclohexanone system to obtain Kq and the radius of gyration. A discussion on the reliability of these methods is given. The Stockmayer-Fixman and Ahmad-Baloch methods are found to be...