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Alkaloids derivatives

Tobacco Alkaloids. The relatively small number of alkaloids derived from nicotinic acid (27) (the tobacco alkaloids) are obtained from plants of significant commercial value and have been extensively studied. They are distinguished from the bases derived from ornithine (23) and, in particular, lysine (24), since the six-membered aromatic substituted pyridine nucleus common to these bases apparendy is not derived from (24). [Pg.539]

Table 9. Alkaloids Derived from Tyrosine as a Ce-C, Fragment and Phenylalanine as a Ce-C3 Fragment... Table 9. Alkaloids Derived from Tyrosine as a Ce-C, Fragment and Phenylalanine as a Ce-C3 Fragment...
Bisindole Alkaloids from Tryptophan. There are two widely different types of alkaloids derived from two tryptophan (26) units. The first is a rather small group of compounds based simply on the dimers of tryptophan which includes compounds such as calycanthine (113) (Table 10),... [Pg.551]

The Opiates. The International Narcotics Control Board—Vienna, tracks the tick production of narcotic dmgs and annually estimates world requkements for the United Nations. Thek most recent pubHcation (100) points out that more than 95% of the opium for Hcit medical and scientific purposes is produced by India and, in a declining trend, only about 600 t was utilized in 1988. This trend appears to be due to the fact that the United States, the largest user of opium for alkaloid extraction, reduced the amount of opium being imported from about 440 t in 1986 to 249 t in 1987 and 224 t in 1988. The United States used about 48 t of morphine (2, R = H) in 1988, most (about 90%) being converted to codeine (2, R = CH3) and the remainder being used for oral adrninistration to the terminally ill (about 2 t) and for conversion to other materials of minor commercial import which, while clearly alkaloid-derived, are not naturally occurring. [Pg.557]

Neuronal Norepinephrine Depleting Agents. Reserpine (Table 6) is the most active alkaloid derived from Rauwolfia serpentina. The principal antihypertensive mechanism of action primarily results from depletion of norepinephrine from peripheral sympathetic nerves and the brain adrenergic neurons. The result is a drastic decrease in the amount of norepinephrine released from these neurons, leading to decrease in vascular tone and lowering of blood pressure. Reserpine also depletes other transmitters including epinephrine, serotonin [50-67-9] dopamine [51-61-6] ... [Pg.141]

Tropine and allied amino-alcohols, alkaloids derived from, 64 neriFropine, 64, 75, 86, 90, 91, 98 (MISr TropIne, 76... [Pg.803]

One of the most significant developmental advances in the Jacobsen-Katsuki epoxidation reaction was the discovery that certain additives can have a profound and often beneficial effect on the reaction. Katsuki first discovered that iV-oxides were particularly beneficial additives. Since then it has become clear that the addition of iV-oxides such as 4-phenylpyridine-iV-oxide (4-PPNO) often increases catalyst turnovers, improves enantioselectivity, diastereoselectivity, and epoxides yields. Other additives that have been found to be especially beneficial under certain conditions are imidazole and cinchona alkaloid derived salts vide infra). [Pg.34]

Dihydrothiazoloquinoline is a key intermediate in the synthesis of natural sulfur-containing pyridoacridine alkaloids—kuanoniamines and derdercitins, where the starting dienone is converted after a multistep reaction sequence to an a-bromo-ketone, which in turn was cyclized with thiourea to the desired dihydrothiazoloquinoline, photochemically convertible to the final alkaloid derivatives 39 (Scheme 21) (92JA10081, 95TL4709, 95JA12460). [Pg.213]

The actual catalyst is a complex formed from osmium tetroxide and a chiral ligand, e.g. dihydroquinine (DHQ) 9, dihydroquinidine (DHQD), Zj -dihydroqui-nine-phthalazine 10 or the respective dihydroquinidine derivative. The expensive and toxic osmium tetroxide is employed in small amounts only, together with a less expensive co-oxidant, e.g. potassium hexacyanoferrate(lll), which is used in stoichiometric quantities. The chiral ligand is also required in small amounts only. For the bench chemist, the procedure for the asymmetric fihydroxylation has been simplified with commercially available mixtures of reagents, e.g. AD-mix-a or AD-mix-/3, ° containing the appropriate cinchona alkaloid derivative ... [Pg.257]

Table 1.12 Cinchona alkaloid-derived phase-transfer catalysts for asymmetric Darzens reactions. Table 1.12 Cinchona alkaloid-derived phase-transfer catalysts for asymmetric Darzens reactions.
Several groups of drugs that bind to tubulin at different sites interfere with its polymerization into microtubules. These drugs are of experimental and clinical importance (Bershadsky and Vasiliev, 1988). For example, colchicine, an alkaloid derived from the meadow saffron plant Colchicum autumnale or Colchicum speciosum), is the oldest and most widely studied of these drugs. It forms a molecular complex with tubulin in the cytosol pool and prevents its polymerization into microtubules. Other substances such as colcemid, podophyllotoxin, and noco-dazole bind to the tubulin molecule at the same site as colchicine and produce a similar effect, albeit with some kinetic differences. Mature ciliary microtubules are resistant to colchicine, whereas those of the mitotic spindle are very sensitive. Colchicine and colcemid block cell division in metaphase and are widely used in cytogenetic studies of cultured cells to enhance the yield of metaphase plate chromosomes. [Pg.21]

Wiesler U-M, Weil T, Mullen K (2001) Nanosized Polyphenylene Dendrimers. 212 1-40 Williams RM, Stocking EM, Sanz-Cervera JF (2000) Biosynthesis of Prenylated Alkaloids Derived from Tryptophan. 209 97-173 Wirth T (2000) Introduction and General Aspects. 208 1-5 Wirth T (2003) Introduction and General Aspects. 224 1-4... [Pg.239]

Williams RM, Stocking EM, Sanz-Cervera JF (2000) Biosynthesis of Prenylated Alkaloids Derived from Tryptophan. 209 97-173... [Pg.270]

C18-0138. Quinine, an alkaloid derived from a free that grows in tropical rain forests, is used in the treatment of malaria. Like all alkaloids, quinine is a sparingly soluble weak base 1.00 g of quinine will dissolve in 1.90 X 10 L of water, (a) What is the pH of a saturated solution of quinine (b) A 100.0-mL sample of saturated quinine is titrated with 0.0100 M HCl solution. What is the pH at the stoichiometric point of the titration ... [Pg.1347]

The alkaloid derived nitrosamines in cigarettes, cigars and pipe tobacco contribute to the quantities of these carcinogens in the smoke because of their partial transfer (32). [Pg.262]

The plant is known elaborate a series of quite unusual phenanthrene alkaloid derivatives, of which aristoliukine-C, aristofolin A and E, aristolochic acid-la methyl ester, and aristolochic acid. Other chemical constituents found in this plant are flavonoid glycosides such as kaempferol-3-O-rutinoside and quercetin kaempferol-3-O-rutinoside (3,4). Exposure to Aristolochiaceae family is associated with the development of cancer in humans. A significant advance is the toxicological effects of aristolochic acid has been provided by the work of Pezzuto et al. They showed that aristolochic acid is a mutagen... [Pg.20]

Hindmarch I, Parrott AC and Lanza M (1979). The effects of ergot alkaloid derivative (Hydergine) on aspects of psychomotor performance, arousal, and cognitive processing ability. Journal of Clinical Pharmacology, 19, 726-732. [Pg.268]

The answer is c. (Hardman, pp 1260—1262.) Paclitaxel is a large structural molecule that contains a 15 membered taxane ring system. This anti cancer agent is an alkaloid derived from the bark of the Pacific yew tree. Its chemotherapeutic action is related to the microtubules in the cell. Paclitaxel promotes microtubule assembly from dimers and causes microtubule stabilization by preventing depolymerization. As a consequence of these actions, the microtubules form disorganized bundles, which decreases... [Pg.98]

Dipolarophiles D14. The 1,3-dipolar cycloaddition of nitrones to dimethyl maleate and dimethyl fumarate is widely used in the synthesis of polyhydroxy alkaloid derivatives of dihydroindolizidinone (81), pyrrolizidine (119), (—)-codonopsinine, and (+ )-hyacinthacines Ai and A2 (312). In cases of unstable nitrones, syntheses of cycloadducts are performed in situ (81). [Pg.364]


See other pages where Alkaloids derivatives is mentioned: [Pg.536]    [Pg.537]    [Pg.537]    [Pg.540]    [Pg.478]    [Pg.29]    [Pg.31]    [Pg.400]    [Pg.36]    [Pg.487]    [Pg.164]    [Pg.353]    [Pg.99]    [Pg.262]    [Pg.229]    [Pg.1409]    [Pg.19]    [Pg.947]    [Pg.461]    [Pg.169]    [Pg.237]    [Pg.237]    [Pg.121]    [Pg.363]    [Pg.374]   
See also in sourсe #XX -- [ Pg.22 ]

See also in sourсe #XX -- [ Pg.230 ]




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Acetate, alkaloids derived from

Active Sites in Cinchona Alkaloids and Their Derivatives

Ajmaline alkaloids derivatives

Alkaloid Derivatives as Asymmetric Phase-transfer Catalysts

Alkaloid Derivatives of Lysergic Acids

Alkaloid-derived nitrosamines

Alkaloids Derived from 5,10b-Ethanophenanthridine

Alkaloids Derived from Both Tyrosine and Phenylalanine

Alkaloids Derived from Dibenzofuran

Alkaloids acetate-derived

Alkaloids and Derivatives

Alkaloids benzodiazepine derived

Alkaloids derivation from polyketides

Alkaloids derived by amination reactions

Alkaloids derived from

Alkaloids derived from Krebs cycle

Alkaloids derived from anthranilic acid

Alkaloids derived from histidine

Alkaloids derived from lysine

Alkaloids derived from nicotinic acid

Alkaloids derived from ornithine

Alkaloids derived from phenylalanine

Alkaloids derived from tryptophan

Alkaloids derived from tyrosine

Alkaloids phenylalanine-derived

Alkaloids photochemical deriv

Alkaloids tryptamine-derived

Alkaloids tryptophan-derived alkaloid biosynthetic pathways

Alkaloids, polyamine derived

Alkylation glycine imines using alkaloid derived

Alkyne Cinchona Alkaloids, Their Derivatives, and Basic Transformations

Amino Acid Tryptophan Indole Alkaloids and Derivatives

Anthranilic acid derived alkaloids

Anthranilic acid tryptophan-derived alkaloids

Apparicine-derived alkaloids

Arginine-derived alkaloids

Aristolochic acid derivative alkaloids

Asymmetric organocatalysts alkaloid derivatives

Benzylisoquinoline alkaloids derivatives

Cinchona Alkaloid Derivatives with a Sulfonamide, Urea, Thiourea, Squaramide, or Guanidine Function

Cinchona alkaloid derivatives

Cinchona alkaloid derived quaternary

Cinchona alkaloid derived quaternary ammonium salts

Cinchona alkaloid-derived enantioselective

Cinchona alkaloid-derived enantioselective development

Cinchona alkaloid-derived enantioselective separation materials

Cinchona alkaloids and derivatives

Cinchona alkaloids derived amines

Cinchona alkaloids oxindole derivatives

Collective Total Synthesis of Tryptophan-Derived Alkaloids

Derivatives of Ergot Alkaloids

Ellipticine derived alkaloids

Enantioselective cinchona alkaloid derivatives

Ergot alkaloids dihydro-derivatives

Evolution of Cinchona Alkaloid-Derived Chiral Separation Materials

Gentianine derived alkaloids

Guanidine-derived alkaloids

Hetero-Diels-Alder reaction cinchona alkaloid derivatives

Histamine alkaloids derivation from

Imidazole-derived alkaloids

Indole derivatives alkaloids

Indole derived alkaloids

Isoquinoline derived alkaloids

Isoquinoline-derived alkaloids synthesis

Lysergic acid derivatives peptide alkaloids

Marine alkaloids derivatives

Michael reactions cinchona alkaloid derivatives

Monoterpene alkaloids derivatives

Monoterpene-derived indole alkaloids

Monoterpenes derived indole alkaloids

Morphine synthetic derivatives, opium alkaloids

Nicotinic acid (vitamin alkaloids derived from

Nicotinic acid-derived alkaloids

Opium, alkaloids derivatives

Ornithine-derived alkaloids

Phase-transfer catalysis conditions cinchona alkaloid-derived catalyst

Physostigmine plant-derived alkaloids

Polyketide derived alkaloids

Proline derivatives, alkaloid synthesis from

Protopine alkaloids derivatives

Pyridine Derivatives and Alkaloids

Pyrrole and Imidazole-Derived Alkaloids

Pyrrole-derived alkaloids

Pyrrolidine derivatives pyrrolizidine alkaloids from

Secologanine derived alkaloid

Strecker reaction cinchona alkaloid derivatives

Synthesis of Tyrosine-Derived Alkaloids

Tobacco alkaloids, nitrosamines derived from

Tryptophan-derived alkaloids

Tryptophan-derived alkaloids hydrogenation

Tyrosine-derived alkaloids

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