Related article: CH 2 OH Many of the aromatic constituents of plants contain hydroxy substituents and are phenolic. There is a wide variety of phenolics in medicinal plants and they range in chemical structure from simple phenolic acids (Figure 3), e.g. caffeic acid from artichoke, to Acai Berry 500 complex tannins (see Appendix 2, Table 20). Where chemical structures are included in a monograph they may be the active principles or they may be compounds that can be used as chemical markers Acai Berry Uk for that plant, i.e. they are present in significant Acai Berry Site quantities or are otherwise characteristic for a particular plant. As some compounds are of common occurrence in medicinal plants, their chemical structures are not necessarily included within a monograph. Some of the commonly encoun- tered natural products, including mono-, sesqui-, Acai Berry Product di- and triterpenes, flavonoids and tannins, are briefly summarised below. COOH Acai Berry Store p-Hydroxybenzoic acid Protocatechuic acid Vanillic acid Gallic acid R 1 R 2 R 3 H OH Acai Berry Price H Acai Berry Singapore OH OH H OCH3 OH H OH OH OH Terpenes Terpenes are derived from two C5 units (isopentane), dimethy- Order Acai Berry lallylpyrophosphate and isopentenylpyrophosphate. The mono- terpenes contain two Acai Berry Natural isopentane units (CIO) and are constituents of many volatile oils (see Appendix 2, Table 21). Some of the more common monoterpenes are shown in Figure 4. Sesquiterpenes contain three isopentane units (C15) and occur as different skeletal types, e.g. eudesmane, germacrene, guaiane (Figure 5). A large number of sesquiterpenes contain Acai Berry Cost a y-lactone ring and these are known as sesquiterpene lactones. Some sesquiterpene lactones are allergenic (see Appendix 2, Table 11). Examples of different skeletal types of molecule, including eudesmolide, germacranolide and guaianolide (e.g. constituents of comfrey) and pseudoguaia- nolide (e.g. matricine, chamomile), are Super Acai Berry illustrated in Figure 5. Diterpenes are derived from four isopentane units (C20) and examples of abietane (e.g. carnosic acid from sage), daphnane, kaurene, labdane Acai Berry S (e.g. rotundifarine from agnus castus), taxane and Acai Berry Vitamin tigliane are given in Figure 6. The ginkgolides from ginkgo are What S Acai Berry examples 100 Acai Berry of complex diterpenes. Triterpenes are derived from six isopentane units (C30), and some commonly occurring com- pounds are Acai Berry 100 illustrated in Figure 7, e.g. campesterol, P-sitosterol, Acai Berry In Uk stigmasterol, a- and P-amyrin, oleanoic and ursolic acids. Cardiac glycosides (cardenolides, see Appendix 2, Acai Berry In India Table 2) and saponins (see Appendix 2, Table 19) are examples of triterpenes that are less widely distributed in plants than the triterpenes illustrated Acai Berry India in Figure 7. *,