Alkaloids (eBook)

Chemistry, Biology, Ecology, and Applications

Tadeusz Aniszewski (Autor)

eBook Download: PDF | EPUB

2015 | 2. Auflage
496 Seiten
Elsevier Science (Verlag)
978-0-444-59462-4 (ISBN)

Infos

Alkaloids - Secrets of Life: Alkaloid Chemistry, Biological Significance, Applications and Ecological Role, Second Edition provides knowledge on structural typology, biosynthesis and metabolism in relation to recent research work on alkaloids, considering an organic chemistry approach to alkaloids using biological and ecological explanation. The book approaches several questions and unresearched areas that persist in this field of research. It provides a beneficial text for academics, professionals or anyone who is interested in the fascinating subject of alkaloids. Each chapter features an abstract. Appendices, a listing of alkaloids, and plants containing alkaloids are all included, as are basic protocols of alkaloid analysis. - Presents the ecological role of alkaloids in nature and ecosystems interdisciplinary - Examines alkaloids from chemistry, biology and ecology viewpoints - A single handy reference volume comprehensively reviews the origin of alkaloids and their biological uses - Over 80% new information, including new chapters on the ecological role of alkaloids in nature and ecosystems and extraction of alkaloids

Former (retired 2014) Professor in Applied Botany, University of Eastern Finland, Faculty of Science and Forestry, Department of Biology, Research and Teaching Laboratory of Applied Botany, Joensuu Campus. Internationally known, Chair of Phytochemical Section of the Botanical Society of America. Lifetime scientific title of docent in applied botany. Gold Medal for a Long Service to the Scientic Community.

Textauszug

Chapter 1

Definition, typology, and occurrence of alkaloids

Abstract

Alkaloids are a group of molecules with a relatively large occurrence in nature around the globe. They are very diverse chemicals and biomolecules, but they are all secondary compounds and are derived from amino acids or from the transamination process. Alkaloids are classified according to the amino acids that provide their nitrogen atom and part of their skeleton. Similar alkaloids can have quite different biosynthetic pathways and different bioimpacts. Alkaloids are derived from l-lysine, l-ornithine, l-tyrosine, l-tryptophan, l-histidine, l-phenylalanine, nicotinic acid, anthranilic acid, acetate, or amination and transamination reactions. The terpenoid, steroid, and purine alkaloids are also important. Millions of people around the globe use purine alkaloids every day whether starting the day with a cup of coffee or drinking a cup of tea in the afternoon. Alkaloids also occur in the animal kingdom. Unlike plants, the source of these molecules in an animal’s body can be endogenous or exogenous. Alkaloids are molecules participating in both producer and consumer chains in nature. They are vital in feeding and enjoy activation, aggression, and defense of various species. Homo sapiens is one of them.

Keywords

Alkaloid

alkaloid derivation

alkaloid occurrence

heterocycles

molecular precursors

protoalkaloids

pseudoalkaloids

true alkaloids

Chapter Outline

1.1 Definition   2

1.2 Typology of alkaloids   7

1.2.1 Bioecological classification of alkaloids   7

1.2.2 Chemotechnological classification of alkaloids   7

1.2.3 Chemo-molecular classification of alkaloids   8

1.2.4 Biosynthetic shape-classification of alkaloids   8

1.2.4.1 True alkaloids   8

1.2.4.2 Protoalkaloids   14

1.2.4.3 Pseudoalkaloids   15

1.3 Occurrence in nature   15

1.3.1 The Dogbane botanical family (Apocynaceae)   17

1.3.2 The Aster botanical family (Asteraceae)   22

1.3.3 The Logan botanical family (Loganiaceae)   24

1.3.4 The Poppy botanical family (Papaveraceae)   26

1.3.5 The Citrus botanical family (Rutaceae)   29

1.3.6 The Nightshade botanical family (Solanaceae)   32

1.3.7 The Coca botanical family (Erythroxylaceae)   35

1.3.8 The Borage botanical family (Boraginaceae)   35

1.3.9 The Legume botanical family (Fabaceae)   37

1.3.10 The Monseed botanical family (Menispermaceae)   53

1.3.11 The Berberry botanical family (Berberidaceae)   55

1.3.12 The Buttercup botanical family (Ranunculaceae)   56

1.3.13 The Lily botanical family (Liliaceae)   58

1.3.14 The Coffee botanical family (Rubiaceae)   60

1.3.15 The Amaryllis botanical family (Amaryllidaceae)   63

1.3.16 The Oleaster botanical family (Elaeagnaceae)   64

1.3.17 The Caltrop botanical family (Zygophyllaceae)   65

1.3.18 Mushroom   65

1.3.19 Moss   67

1.3.20 Fungus and bacter   68

1.3.21 Animals   70

References   73

Docendo discimus.

Seneca

1.1 Definition

The definition of the term alkaloid is not simple and, in many cases, is a source of academic controversy. This controversy was especially active at the beginning of 20th century, when the progress in chemical research on alkaloids occurred. Many new achievements in the field have been opposed and very critically discussed. Moreover, scientific discussions around the alkaloids continue.8,23 Alkaloids were fascinating subject in the past, and nowadays, they are an object of strong scientific and economic interest, especially in medicine and the pharmaceutical industry. Difficulties with the definition of such a group of secondary, natural molecules as alkaloids stem, also nowadays, from the similarities between alkaloids and other secondary compounds, despite their diversity and occurrence in complexes with different moieties, sometimes classified as different biochemical types, such as peptides, proteins, and sugars. Moreover, alkaloids were used for long time before their discovery as chemical molecules with a unique nomenclature. For example, the alkaloid quinine was use in herbal form by native people of America many hundred years before it was given that name. Awareness of the possibility of using this herbal medicine in the cure of malaria came in the year 1638, when some aristocrats were officially cured of malaria by this mean.87 Attempts to define the term alkaloid originated at the time of the discovery of these compounds. Friedrich Sertürner, an apothecary’s assistant from Westphalia, first isolated morphine (Figure 1.1), one of the most important alkaloids in the applied sense.43 This was in 1805 and proved a significant step forward in chemistry and pharmacology.10,70,366 Using the method developed by Friedrich Sertürner, the pharmaceutical researchers Pierre Joseph Pelletier and Joseph Benaimé Caventou isolated, from 1817 to 1821, a remarkable range of other alkaloids (Figure 1.2), such as brucine (a close relative of strychnine), febrifuge, quinine, caffeine, and veratrine.42–44 After that, the first attempts to discover alkaloids by synthetic means took place in the middle of 1800s. One of them was an attempt to produce synthetic quinine in the laboratory. However, many other chemical compounds have been made synthetically before quinine, which had been done only in 1900s. Nowadays, the synthetic production of some important alkaloid is more common than their isolation from natural sources. The progress in both theoretical and applied chemistry led to the synthesis such new compounds, which do not exist in the nature and can only be manufactured.

■ Figure 1.1 Contemporary scheme of morphine. Friederich Surtürner, who first isolated this alkaloid in an impure form in 1805, knew that it was converted from the pathway of Tyrosine, Tyr. The correct morphine structure was determined by Gulland and Robinson in 1923. Moreover, even 200 years after Surtürner’s isolation, scientists are still discussing this alkaloid from a molecular point of view. This is a good example of the scientific evolution of knowledge of alkaloids.

■ Figure 1.2 Some alkaloids isolated by pharmaceutical researchers Pierre Joseph Pelletier and Joseph Beinamé Caventou during 1817–1821. They did not know the exact structures. The compounds thus isolated are combinations of alkaloids rather than one pure alkaloid.

The term alkaloid was first mentioned in 1819 by W. Meißner, an apothecary from Halle. He observed that these compounds appeared “like alkali” and so named them alkaloids.67

For the biologist, the alkaloid is a pure and perfect natural product. From the biological point of view, the alkaloid is any biologically active and heterocyclic chemical compound that contains nitrogen and may have some pharmacological activity and, in many cases, medicinal or ecological use.11 This definition, as a relatively wide one based on application, can be criticized as inexact. However, it presents a general picture of what kinds of compound are under consideration. The biological and chemical nature of this group of compounds leads to the conclusion that each definition of alkaloids...

Produkt-Details

• Erscheint lt. Verlag: 25.4.2015
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Biologie
• Themenwelt: Naturwissenschaften ► Chemie ► Organische Chemie
• Themenwelt: Technik
• ISBN-10: 0-444-59462-0 / 0444594620
• ISBN-13: 978-0-444-59462-4 / 9780444594624