Indole-3-acetic acid naturally occurring

Naturally Occurring Compounds. Many derivatives of iadole are found ia plants and animals where they are derived from the amino acid tryptophan. Several of these have important biological function or activity. Serotonin [50-67-9] (12) functions as a neurotransmitter and vasoconstrictor (35). Melatonin [73-31-4] (13) production is controlled daily by the circadian cycle and its physiological level iafluences, and seasonal rhythms ia humans and other species (36). Indole-3-acetic acid [87-51-4] (14) is a plant growth stimulant used ia several horticultural appHcations (37). 

It is important to keep in mind that any extraction of organic matter from soil will include both naturally occurring organic matter and organic contaminants. Separating the two at some later stage of analysis is thus an essential analytical step. For example, extraction of soil with hexane or dichloromethane will extract both l,l,l-trichloro-2,2-di(4-dicholorphenyl)ethane (DDT), a contaminant, and octadecanoic acid, a natural fatty acid. Also, the herbicide 2,4-dichlorophenoxy acetic acid, a contaminant, and indole-3-acetic acid, a natural plant hormone, are both extracted by water (see Figure 12.3). These... 

The natural auxins are represented by a single compound, indole-3-acetic acid (IAA), which occurs as the free acid and in various "bound" forms, including a thioglucoside, glycosyl esters, and IAA peptides. For a recent discussion see the book chapter by Bandurski and Nonhebel (2) in Wilkins (3). 

Chloro-indole-3-acetic acid (4-Cl-IAA) is the second naturally occurring auxin to be found... 

The total synthesis of ellipticine by Miller el al. [11] is one of the first syntheses of naturally occurring indole alkaloids using Pd(OAc), via the oxidative cyclization mechanism (Scheme 2). Exposure of 6-anilino-5,8-dimethylisoquinoline (9) to two equivalents of Pd(OAc)j in TFA/AcOH facilitated the oxidative cyclization to the desired ellipticine (10). Recently, the same indole formation strategy that uses the Pd(OAc),-mediated oxidative cyclization has been the cornerstone of several synthetic approaches directed toward ellipticine analogs. For instance, oxidative cyclization of diphenylamine 11 was carried out with Pd(OAc), in acetic acid to provide... 

Conjugates of indole-3-acetic acid. Listed are the naturally occurring conjugates of lAA and 4-Cl-IAA from plants and plant pathogenic bacteria described to date. With the exception of the Parthenocissus spp. callus tissue, these compounds have been isolated from tissues not exposed to exogenous sources of lAA. Compounds reported prior to 1982 are discussed in a comprehensive review of lAA conjugates (ref. 2 [83]). 

Hormones are produced naturally by plants, while plant growth regulators are applied to plants by humans. Plant growth regulators may be synthetic compounds (e.g., Cycocel) that mimic naturally occurring plant hormones, or they may be natural hormones that are extracted from plant tissue (e.g., indole-3-acetic acid). 

In 2002, Baran and Corey [44] described the total synthesis of (+)-austamide and its naturally occurring relatives (+)-deoxyisoaustamide and (-l-)-hydratoaustamide (Scheme 9.15). The efficient synthesis of these compounds featured a palladium(II)-mediated cyclization to form an eight-membered ring as the key step. Indole 102 was treated with stoichiometric palladium acetate in a 1 1 1 mixture of acetic acid, water and tetrahydrofuran (THP) to produce dihydroindoloazocine 103 in 29% yield. A unique mechanism, illustrated in Scheme 9.15, was proposed for this transformation. After palladation of the indole at C(2), 7-exo cyclization provides intermediate 108, which forms cationic intermediate 109 upon acid-mediated heterolysis. This intermediate undergoes a deprotonation and subsequent migration of the indolyl species to afford product 103. A possible alternative mechanism... 

Indole-3-acetic acid (lAA) is a naturally occurring auxin with broad physiological effects. The production of LAA by Ga. diazotrophicus was first reported by... 

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