Heme Enzymes: Nature’s Versatile Catalysts

Non-heme iron enzymes: contrasts to heme catalysis.

Non-heme iron enzymes catalyze a wide range of O(2) reactions, paralleling those of heme systems. Non-heme iron active sites are, however, much more difficult to study because they do not exhibit the intense spectral features characteristic of the porphyrin ligand. A spectroscopic methodology was developed that provides significant mechanistic insight into the reactivity of non-heme ferrous act...

Tuning P450 Enzymes as Oxidation Catalysts

The development of catalytic systems for the controlled oxidation of C−H bonds remains a highly sought-after goal in chemistry owing to the great utility of such transformation toward expediting the synthesis and functionalization of organic molecules. Cytochrome P450 monooxygenases are the catalysts of choice in the biological world for mediating the oxidation of sp and sp C−H bonds with a hig...

Nucleophilic Chiral Phosphines: Powerful and Versatile Catalysts for Asymmetric Annulations.

Recent advances in chiral-phosphine-catalyzed asymmetric annulation reactions; including annulations of allenes, alkynes, Morita-Baylis-Hillman (MBH) carbonates, and ketenes; and their applications in the synthesis of bioactive molecules and natural products are reviewed.

The Natures of Nonconfigurationality

Population, development, and human natures

At the dawn of this new millennium, the human enterprise is quickly becoming a globally unified one. Yet numerous obstacles and pitfalls remain in the path of a full and fair unification. A substantial fraction of the world’s population is well-off and increasingly connected through trade and communications systems. But an even larger fraction is struggling to make ends meet and is only sketchi...