Aryl-substituted allylic chlorides are accommodated by a self-assembled cage in such a restricted orientation that the internal reaction sites are shielded while the external ones are exposed. This non-covalent protection enhances terminal regioselectivity in the allylic substitution.

Lytic polysaccharide monooxygenases (LPMOs) have changed our understanding of lignocellulosic degradation dramatically over the last years. These metalloproteins catalyze oxidative cleavage of recalcitrant polysaccharides and can act on the C1 and/or C4 position of glycosidic bonds. Structural data have led to several hypotheses, but we are still a long way from reaching complete understanding ...

Quinoline was used to probe the steric and electronic contributions to rates of aromatic oxidation of nitrogen-containing, multiring substrates by cytochrome P450 (P450) enzymes. The regioselectivity of the P450 oxidation of quinoline was determined experimentally by identifying and measuring the ratios of metabolites. The laboratory results were compared with those obtained computationally by ...

The [2 + 2] photochemical cycloadditions (the Paternò-Büchi reaction) of 5- or/and 6-methyl substituted uracil derivatives with 4,4'-disubstituted benzophenones generate two series of regioisomeric oxetanes, 3 and 4. The regioselectivity (3/4) and the photochemical efficiency are strongly dependent on methyl substituent(s) at the C5-C6 double bond of the uracils. The more the methyl groups at t...

The fungal iterative nonreducing polyketide synthases (NRPKSs) synthesize aromatic polyketides, many of which have important biological activities. The product template domains (PT) embedded in the multidomain NRPKSs mediate the regioselective cyclization of the highly reactive polyketide backbones and dictate the final structures of the products. Understanding the sequence-activity relationshi...

A palladium-catalyzed reaction of 2-haloaryl allene with 2-alkynylphenol is described, leading to 6H-naphtho[2,3-c]chromenes in good to excellent yields. This transformation proceeds efficiently with excellent chemoselectivity and regioselectivity.

The allylic hydrogen is found to have a dramatic effect on the regioselectivity of the Wacker oxidation, leading to the postulation that an agostic hydrogen or enyl (sigma + pi) complex helps to stabilise the key intermediate.

An efficient method towards synthesis of 1,10-phenanthrolines is described. Through Lewis acid-catalyzed annulation reaction between 3-ethoxycyclobutanones and 8-aminoquinolines, a variety of unsymmetric and symmetric 1,10-phenanthroline derivatives were readily prepared with high regioselectivity at room temperature.

Haloarenes undergo direct borylation using amine : BCl3 : AlCl3 in the ratio of 1 : 1 : 2. After esterification the pinacol boronate esters are isolated in good yield with regioselectivity controlled by steric and electronic effects.

CYP4Z1 is an "orphan" cytochrome P450 (P450) enzyme that has provoked interest because of its hypothesized role in breast cancer through formation of the signaling molecule 20-hydroxyeicosatetraenoic acid (20-HETE). We expressed human CYP4Z1 in Saccharomyces cerevisiae and evaluated its catalytic capabilities toward arachidonic and lauric acids (AA and LA). Specific and sensitive mass spectrome...