Oxygen atom transfer family

The final family of molybdenum enzymes consists of enzymes from bacterial and archaeal sources that also catalyze oxygen atom transfer reactions for the most part, although formate dehydrogenase and polysulfide... 

As for the reactions catalyzed by members of this third family of molybdenum enzymes, there are several variations from the principal theme of oxygen atom transfer. Formate dehydrogenase from E. coli catalyzes the oxidation of formate to CO2, a reaction that isotope studies have shown does not pass through a bicarbonate intermediate (Khangulov et al., 1998). Instead, it appears likely that C02is formed by direct hydride transfer from substrate to the molybdenum center. Polysulfide reductase is another molybdenum enzyme that catalyzes a non-canonical reaction the... 

The second category includes enzymes that typically catalyze proper oxygen atom transfer reactions to or from an available electron lone pair of a substrate, and can be further subdivided into two families. The first family includes sulfite oxidase and assimilatory nitrate reductase, the physiological functions of which are to reduce nitrate to nitrite in the first stage of its reduction to ammonia for use by the plant cell. The second family comprises bacterial enzymes such as dimethylsulfoxide... 

In terms of the reaction catalyzed, molybdopterin-containing enzymes can be divided in two groups those that mediate oxygen atom transfer, such as dimethyl sulfoxide (DMSO) reductase and sulfite oxidase (SO), and those that catalyze hydroxylation reactions of aromatic heterocyclic compounds and aldehydes [116], for instance xanthine oxidoreductase (XOR) and aldehyde oxidoreductase (AOR). However, this functional classification does not coincide with structural properties that suggest that the enzymes should be grouped into five families, whose most representative members are (1) DMSO reductase (2) XOR (3) SO (4) aldehyde-... 

Oxidation of thiazoles 137 with HOF MeCN provides easy access to the family of thiazole A-oxides 138 <06CC2262>. The readily made HOF MeCN complex, considered to be one of the best oxygen transfer agents in chemistry, transfers an oxygen atom directly to thiazole-containing compounds without affecting the double bonds of the thiazole moiety. A small amount of /V,SVS -trioxide 139 is also formed in this oxidation. 

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