Naturally-occurring classification

Classification of the anabolic steroids is based on chemical stmctures and associated actions. A review of the biosynthesis and metabolism of the naturally occurring estrogens and androgens is available (1). Names, descriptions, approval dates, and recommended doses of the commercial products are found in References 1, 8, and 9. Although steroids may be orally active, the FDA approved mode of adrninistration is the subcutaneous implant. Effective dose is lower with implant rather than oral adrninistration. 

Technical Enzymes. When an enzyme is used for a technical appHcation, ie, industrial but nonfood and nonfeed, its regulatory status is determined by its properties as a naturally occurring substance. These properties determine the classification and consequent labeling in accordance with existing schemes for chemicals. It should be noted that enzymes are not Hsted as dangerous chemicals. 

Mikes and Turkova have given a classification of naturally occurring hydroxamic acids in terms of their biological function or activity. They have distinguished (a) growth factors, e.g., ferri-chromes, mycobactin, and ferrioxamines, ferrichrysins, ferrirubins, etc. (6) antibiotics, e.g, aspergillic acid, mycelianamide, albomycin, nocardamine and (c) microbial pigments such as pulcherrimin. 

As a starting point, the book reviews the general properties of the raw materials. This is followed by the different techniques used to convert these raw materials to the intermediates, which are further reacted to produce the petrochemicals. The first chapter deals with the composition and the treatment techniques of natural gas. It also reviews the properties, composition, and classification of various crude oils. Properties of some naturally occurring carbonaceous substances such as coal and tar sand are briefly noted at the end of the chapter. These materials are targeted as future energy and chemical sources when oil and natural gas are depleted. Chapter 2 summarizes the important properties of hydrocarbon intermediates and petroleum fractions obtained from natural gas and crude oils. 

Further to section III(C), we shall see that type I dioxygen complexes can be formed in solution via intermediates of a type 11(F) structure. Consequently, sections IV( ) and IV(F) will tend to overlap in places. The dioxygen adducts of some new synthetic metal porphyrins belong to the 11(F) classification. However, a discussion of the dioxygen adducts of naturally occurring and synthetic metal porphyrins is postponed until section V. 

In this classification of the compounds into mucopolysaccharides, mucoproteins, and mucolipids, it must be emphasized most strongly that since the mode of isolation of any naturally occurring high polymer influences profoundly its composition and biological properties, the difference between divisions is not always sharp and there may be some degree of overlapping. 

Multiple classifications can be thought of when attempting to put an order to the vast family of radicals formed by the chalcogen radicals. They can be divided into naturally occurring and synthetic ones, homo-nuclear and hetero-nuclear systems, etc. In this chapter, we will focus on the five-membered rings of group 15/16 elements since a substantial body of work in recent years has been devoted to them. However, some other radicals have been isolated and their chemistry and properties reviewed recently.2,3... 

If a second deviation of the same nature occurs simultaneously with the first deviation, does the re-occurring deviation fall into the classification precursor ... 

The creatures of the world, both animals and plants, produce a wide range of biologically active substances. Biologically active substances produced by animals or plants that cause an adverse effect are called toxins. Toxins refers only to toxic agents produced by animals and plants, not toxic substances such a lead or pesticides. The classification of a substance as a toxin tends to be in the eye of the beholder. Is caffeine, a naturally occurring agent in many plants, a toxin or just a pharmacologically active compound or both ... 

Naturally Occurring Substances.—Beyeria (Euphorbiaceae) species have been the source of a number of tetracyclic diterpenoids. Some of these were new or poorly defined species and their classification has now been clarified. " The presence of enf-kaurenal has again been recorded in Fusarium monoliforme, whilst ent-kaur-16-en-19-oic acid (72) has been isolated from Mikania hirsutissima (Composi-tae). Microbiological hydro xylation of ent-kaur-16-en-19-oic acid by... 

The nomenclature and classification of monosaccharides is further complicated by the presence of chiral carbons within monosaccharides. In the late nineteenth century it was ascertained that the configuration of the last chiral carbon in each of the naturally occurring monosaccharides is the same as that for (-i-)-glyceraldehyde. This configuration was designated as D and it was determined that all naturally occurring monosaccharides were in the D configuration. 

There are two fundamental classifications of flavors (1) natural, and (2) synthetic or artificial. Prior to die early beginnings of organic chemistry (circa 1828). all flavors, essences, aromas, and like substances were derived from naturally occurring materials. 

MINERALOGY. The science of mineralogy is concerned with the formation, occurrence, properties, composition, and classification of minerals. Vnrinus definitions of a mineral have been proposed. Possibly, the most acceptable may be. "a naturally occurring inorganic substance, usually crystalline, possessing a relatively definite chemical composition and physical characteristics. It should be pointed out that some naturally formed organic substances, particularly of an economic resource nature, are sometimes classified as minerals. 

---