Hydroxylation alicyclic

Microsomal oxidations may be subdivided into aromatic hydroxylation aliphatic hydroxylation alicyclic hydroxylation heterocyclic hydroxylation N-, S-, and O-dealkylation N-oxidation N-hydroxylation S-oxidation desulfuration deamination and dehalogenation. 

Alicyclic hydroxylation. Hydroxylation of saturated rings yields monohydric and dihydric alcohols. For instance, cyclohexane is metabolized to cyclohexanol, which is further hydroxylated to frcms-cyclohexane-l,2-diol (Fig. 4.11). With mixed alicyclic/aromatic, saturated and unsaturated systems, alicyclic hydroxylation appears to predominate, as shown for the compound tetralin (Fig. 4.12). 

A recent example of a species difference in metabolism causing a difference in toxicity is afforded by the alicyclic hydroxylation of the oral antiallergy drug, proxicromil (Fig. 5.11). After chronic administration, this compound was found to be hepatotoxic in dogs but not in rats. It was found that dogs did not significantly metabolize the compound by alicyclic oxidation, whereas rats, hamsters, rabbits, and man excreted substantial proportions of metabolites in the urine. In the dog, biliary excretion was the route of elimination of the unchanged compound,... 

The cyclohexyl group is commonly found in many medicinal agents, and is also susceptible to mixed-function oxitlti-tion (alicyclic hydroxylation)." Enzymatic introduction of a hydroxyl gmup into a monosubstituted cyclohexane ring generally occurs at C-3 or C-4 and can lead to cis and trims conformational stereoisomers, as shown in the diagrammed. scheme. 

Two human urinary metabolites of phencyclidine (PCPi have been identified as the 4-hydroxypiperidyl and 4-hy-droxycyclohcxyl derivatives of the parent compound. " Thus, from these results, it appears that alicyclic" hydroxylation of the six-memhered piperidyl moiety may parallel closely the hydroxylation pattern of the cyclohexyl moiety. 

Gibberellins Growth, complex 5-ring hydroxylated alicycle. Requires iron containing enzyme for synthesis... 

The concept of a group is especially important in organic chemistry. A functional group represents a set of atoms that is closely linked with chemical reactivity and defined classes of substances. For instance, the functional group hydroxyl, -OH, is characteristic of the classes alcohol, phenol and enol. Alcohols are often represented by the general formula R-OH, in which R- represents a hydrocarbon group typical of aliphatic and alicyclic substances. 

Ozone reacts slowly with many types of water contaminants such as alicyclic taste or odor compounds, e. g. geosmin or THMs and unactivated aromatics such as chlorinated benzenes. Ozone will react faster with certain types of aromatic compounds, e. g. those carrying electron supplying substituents such as the hydroxyl group in phenol. If there is no... 

The hydroxyl group of a primary, secondary, or tertiary acyclic or alicyclic alcohol may be protected by conversion into (a) an ether, (b) a silyl ether, or (c) an ester. The most important method for the protection of a 1,2- or 1,3-diol is conversion into (d) a cyclic acetal. 

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