Furanocoumarins are formed when furor ring is joined with coumarins. The plants of Rutaceae, Leguminosae and Apiaceae are rich sources of furanocoumarins. Depending upon the structure, the furanocoumarins are divided into linear and angular types. Furanocoumarin containing preparations are used externally as well as internally for treatment of leucoderma, psoriasis and skin carcinoma.
They are group of coumarins, derived from benzopyrone. They are related to furanocoumarins and are present in plants of family Apiaceae and Rutaceae.
They represent another group of coumarins, which are widely distributed in Apiaceae and Gramineae.
They are water-soluble constituents, found in the cell sap. They are colourless, crystalline substances containing carbon, hydrogen and oxygen. Some glycosides are peculiar in having nitrogen and sulphur. Glycosides are neutral in reaction. Chemically, glycosides contain a carbohydrate (glucose) and a non-carbohydrate part (aglycone or genin). Alcohol, glycerol or phenol represents aglycones. A glycoside can be readily hydrolysed into its components with ferments or mineral acids.
Glycosides differ in their solubility in water. Some are soluble in ether and alcohol. Amygdalin found in almonds is a familiar example of a glycoside. Benzeldehyde is the decomposition product of amygdalin, responsible for odour and taste of almonds. Glycosides are optically active and are levorotatory.
They are widely distributed in plant flora. They constitute an important part of glycosides (phenolic glycosides), flavonoids, napthodianthrones and tannins. Acylphloroglucinols are group of phenolic compounds having significant antidepressant activity.
They contain a three-carbon side chain attached to phenol. Hyroxycoumarins, phenylpropenes and lignans are common examples of phenylpropanoids.
Resins are obtained by oxidization of volatile oils. Resins are brittle, non-volatile, solid substances. Sometimes resins are among the products of oxidization of terpenes. The chemical composition of resins is very complex and contains various compounds including acids.