Phenols naturally occurring

Phenolic compounds are commonplace natural products Figure 24 2 presents a sampling of some naturally occurring phenols Phenolic natural products can arise by a number of different biosynthetic pathways In animals aromatic rings are hydroxylated by way of arene oxide intermediates formed by the enzyme catalyzed reaction between an aromatic ring and molecular oxygen... 

Methylphenol. This phenol, commonly known as o-cresol, is produced synthetically by the gas phase alkylation of phenol with methanol using modified alumina catalysis or it may be recovered from naturally occurring petroleum streams and coal tars. Most is produced synthetically. Reaction of phenol with methanol using modified zeoHte catalysts is a concerted dehydration of the methanol and alkylation of the aromatic ring. 2-Methylphenol [95-48-7] is available in 55-gal dmms (208-L) and in bulk quantities in tank wagons and railcars. 

Di-/ f2 -butyl-4-methylphenol, which is commonly known as BHT (butylated hydroxy toluene), is a widely used phenoHc antioxidant in the stabilization of oils, mbber, and polyolefins (44). BHT is also one of the few phenolic antioxidants approved by the FDA as a direct food additive where it is used to retard the oxidation of naturally occurring oils in food. 

Sulfates of sodium are iadustriaUy important materials commonly sold ia three forms (Table 1). In the period from 1970 to 1981, > 1 million metric tons were consumed aimuaHy ia the United States. Siace then, demand has declined. In 1988 consumption dropped to 890,000 t, and ia 1994 to 610,000 t (1,2). Sodium sulfate is used principally (40%) ia the soap (qv) and detergent iadustries. Pulp and paper manufacturers consume 25%, textiles 19%, glass 5%, and miscellaneous iadustries consume 11% (3). About half of all sodium sulfate produced is a synthetic by-product of rayon, dichromate, phenol (qv), or potash (see Chromium compounds Fibers, regenerated cellulosics Potassium compounds). Sodium sulfate made as a by-product is referred to as synthetic. Sodium sulfate made from mirabilite, thenardite, or naturally occurring brine is called natural sodium sulfate. In 1994, about 300,000 t of sodium sulfate were produced as a by-product another 300,000 t were produced from natural sodium sulfate deposits (4). 

As recently as 1970, only about 30 naturally occurring organohalogen compounds were known. It was simply assumed that chloroform, halogenated phenols, chlorinated aromatic compounds called PCBs, and other such substances found in the environment were industrial pollutants. Now, only a third of a century later, the situation js quite different. More than 5000 organohalogen compounds have been found to occur naturally, and tens of thousands more surely exist. From a simple compound like chloromethane to an extremely complex one like vancomycin, a remarkably diverse range of organohalogen compounds exists in plants, bacteria, and animals. Many even have valuable physiological activity. Vancomycin, for instance, is a powerful antibiotic produced by the bacterium Amycolatopsis orientalis and used clinically to treat methicillin-resistant Staphylococcus aureus (MRSA). 

Shimp RJ, FK Pfaender (1985a) Influence of easily degradable naturally occurring carbon substrates on biodegradation of monosubstituted phenols by aquatic bacteria. Appl Environ Microbiol 49 394-401. 

The CF sheet is prepared by coating an acidic coreactant such as naturally occurring reactive clay, zinc salt of salicylic acid derivatives and zinc modified phenolic resin. 

Table I. Effects of naturally-occurring phenolic compounds on mineral absorption in excised roots.

Incorporation of some xenobiotics (herbicides) into soil humus-complexes occurs via pathways analogous to those for incorporation of naturally occurring phenolic and benzoic acids and do indeed involve phenolic and humus-like constituents... 

The solubility of most metals is much higher when they exist as organometallic complexes.4445 Naturally occurring chemicals that can partially complex with metal compounds and increase the solubility of the metal include aliphatic acids, aromatic acids, alcohols, aldehydes, ketones, amines, aromatic hydrocarbons, esters, ethers, and phenols. Several complexation processes, including chelation and hydration, can occur in the deep-well environment. 

Iodine water is added to an acetic acid sodium acetate buffered sample to reoxidise to iodate any iodine-containing substances produced by reduction of iodate by naturally occurring reducing substances present in the sample. Total iodate (i.e., iodate present in the original sample as iodate plus additional iodate produced by iodine water treatment) is then reacted with phenol solution at... 

A wide variety of xenobiotics can become cross-linked to naturally occurring humic matter by the action of phenyloxidases. These xenobiotics include phenols (e.g., mono-, di-, and tri-substituted chlorophenols, 2,6-xylenol), and anilines (e.g., 4-chloroaniline, 3,4-dichloroaniline, and 2,6-diethylaniline) [17,160]. 

Occolowitz, J.L. Mass Spectrometry of Naturally Occurring Alkenyl Phenols and... 

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