Theme XI: Alkaloids

Alkaloids. Definitions. Types. Structure. Classification of Alkaloids. Opium. Quina-tropane. Ergot-Xanthine-Rauwolfia. Xanthine. Veratrum-Vinca-Misc.

Alkaloids are products from a sequence of biochemical reactions of plants metabolism.

The term is used due to the weak base alkali of these organic substances which make them similar to alkalis.

They are the active ingredients of many plants including about 158 botanical families. Most alkaloids are found in flowering plants but also appear in a small group of non-flowering plants.

Alkaloids are complex structures, as a rule, are specific to a certain families of plants such as hyoscyamine in the Solanaceae and colchicine in the Liliaceae.

The alkaloids belong to the group of substances that along with the antibiotics represent a broad array of resources for treatment and mitigation of various organ dysfunctions, which give them great importance. They are in constant research and screening for the search and synthesis of these molecules.

In the range of alkaloids are the Reserpine with remarkably antihypertensive value and the studied alkaloids of Roseae Vinca used in the treatment of certain cancers.

Alkaloids or similar molecules have been partially synthesized starting from natural structures such as lysergic acid to produce ergonovine.

In its natural state the alkaloids are in the form of salts from organic acids such as lactic, malic, tartaric and citric.

In its chemical structure the basic nitrogen may be bound to one or more functional groups, among which are esters, secondary alcohols, aromatic groups and amides.

Classification of alkaloids

Opium alkaloids

Quina and tropane alkaloids

Xanthine, ergot and rauwolfia alkaloids

Xanthine

Veratrum, vinca and miscellaneous

Active principles

Sterols

Parts of plants

Alkaloids. Definitions. Types. Structure. Classification of Alkaloids. Opium. Quina-tropane. Ergot-Xanthine-Rauwolfia. Xanthine. Veratrum-Vinca-Misc.