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The laccase-catalyzed oxidative coupling of sesamol, a naturally occurring phenolic antioxidant, with O 2 as the oxidant proceeds with high selectivity and delivers a previously unknown trimer in 61% yield. Further experiments demonstrate that the outcome of the sesamol oxidation strongly depends on the catalyst and the oxidant employed.

The laccase-catalyzed domino reaction of o -phenylenediamine and benzaldehydes with aerial oxygen as the oxidant exclusively yields 2-aryl-1 H -benzimidazoles in good to very good yields. It is easy to perform under very mild reaction conditions.

A new single-step transformation of readily available nitroarenes with trialkyl phosphites, which can be performed both under thermal and microwave conditions, delivers dialkyl N-arylphosphoramidates in good yields and short reaction times.

New Pd-mediated reductive heteroannulations of N-allyl diphenylamines accessible through Pd-catalyzed N-arylation and of O-allylethers are reported.

Laccase initiated domino reactions of cyclohexane-1,3-diones with catechols using air as an oxidant afford 3,4-dihydro-7,8-dihydroxy-2 H -dibenzofuran-1-ones with yields ranging from 70% to 97%.

Methanophenazine is a new cofactor from methanogenic archaea. ( S )-Methanophenazine has been synthesized from three building blocks, i.e. 2-hydroxy-phenazine, ethyl ( R )-3-methylglutarate and ( E , E )-farnesyl acetone; a stereodivergent approach from ethyl ( R )-3-methylglutarate warrants the formal synthesis of ( R )-methanophenazine.

A one pot oxidation of cyclic unsaturated carbonyl and carboxylic compounds with ruthenium (III)-chloride and peracetic acid to the corresponding α-oxo-ene-diols (aci-reductones) has been developed.

Chiral, double-activated enophiles in 1,7-dienes 6a - d undergo thermal and Lewis-acid catalyzed intramolecular ene reactions yielding trans-cyclohexanes 7a-d and 8a-d . The extent of diastereoselectivity depends on the reaction temperature. The 1,7-dienes 6 are obtained via Knoevenagel condensation of citronellal 5 with acyclic 1,3-dicarbonyls and analogous compounds 4 . Starting with the diene 6e , however, an intramolecular hetero-Diels-Alder reaction takes place.

By growing Escherichiacoli in the presence of 5-amino [5-13C] laevulinic acid, the enzyme hydroxymethylbilane synthase is produced carrying 13C-labels in its pyrromethane cofactor. It is then proved by 13C-n.m.r. spectroscopy that the cofactor is bound to the protein via the sulphur atom of a cysteine residue.