L-Hyoscyamine

By extraction of Solanacean drugs, especially Atropa belladonna, Hyoscyamus niger or other species. On careful extraction L-hyoscyamine is obtained first, which can be racemized to atropine by addition of alkali in ethanolic solution. 

F. Oprach Durer-StraBe 34 D-79618 Rheinfelden Telefon (07623) 20449 L-Hyoscyamine... 

Dimethyl-l,6-octadien-3-ol Dipentene Duboisine Linalool ( )-Limonene L-Hyoscyamine... 

Hydroxy-phenyl]pentenedioic acid L-Hyoscyamine Sphagnum acid... 

Atropin was obtained from belladonna roots and by racemisation of L-hyoscyamine with dilute alkali or by heating in chloroform solution. The alkaloid was crystallised from alcohol on addition of water, or from chloroform on addition of light petroleum, or from acetone in long prisms, m.p. 118°C, sublimed unchanged when heated rapidly. It is soluble in alcohol or chloroform, less soluble in ether or hot water, sparingly so in cold water (in 450 L at 25°C) and almost insoluble in light petroleum. Atropine is optically inactive. 

Xu A, Havel J, Linderholm K, Hulse J (1995) Development and validation of an LC/MS/MS method for the determination of L-hyoscyamine in human plasma. J Pharm Biomed Anal 14 33-42... 

Spectra for the diastereoisomeric pairs quinine-quinidine, cinchonine-cinchonidine alkaloids are mirror images of each other and mixtures have been determined using CD detection [57]. Spectra for the pilocarpine-isopilocarpine pair were such low quality that they could be used only for qualitative distinction. CD detection combined with UV detection was used to measure enantiomeric excesses in mixtures of L-hyoscyamine and atropine, i.e. racemic hyoscyamine. This subject is returned to in greater depth later. 

The failure to find C02 In the expired air of the mice Indicates that the tropic acid moiety in the atropine molecule Is not metabollzed ln accord with the finding that labeled tropic acid Itself was excreted without loss In the urine. The finding of atropine but no tropic acid In the urine of the mice Indicates that hydrolysis of the ester did not occur rapidly. The latter finding was somewhat unexpected because an esterase capable of hydrolysing atropine is present In the livers of many vertebrate species, although It or a similar enzyme appears In the sera of only a few species (93-95). This enzyme Is also able to hydrolyze L hyoscyamine, troplnyl benzoate, and caramlphen (95). 

Wyant and Dobkln (116) compared atropine, L-fayoscyamlne, and scopolamine for ability to stop salivation Induced by Intravenous Injection of a mixture of carbachol and epinephrine. Scopolamine was slightly more active In this regard than L- hyoscyamine, and both were considerably more active than atropine. 

Atropine is the racemic mixture of l- and o-hyoscya-mine and possesses 50% of the antimuscarinic potency of L-hyoscyamine. Atropine is derived from components of the Belladonna plant and is also present in other plants from the Solanaceae family. Women in ancient times often dripped the plant s juices into their eyes, causing mydriasis and thereby enhancing their beauty. In Italian, Belladonna translates to beautiful lady . In the United States, the atropine autoinjector has been in use since 1973 for the treatment of exposures to chemical warfare nerve agents and insecticides. 

The toxins in Jimsonweed are tropane belladonna alkaloids possessing strong anticholinergic properties. They include hyoscyamine (leaves, roots, seeds) hyoscine (roots) atropine (D,L-hyoscyamine), and scopolamine (L-hyoscine). They act as competitive antagonists to acetylcholine at peripheral and central... 

The calibration graphs were rectilinear in the range of 0-0.5 mg ml l (hyoscyamine plus atropine), 0-0.32 mg ml-1 (scopolamine). 

Prostatectomy is ineffective for relieving irritative voiding symptoms of BPH because prostatectomy does not affect the detrusor muscle of the bladder. These patients may respond to oral anticholinergic agents (e.g., oxybutynin or L-hyoscyamine), which improve bladder compliance and decrease detrusor muscle irritability, as discussed in Chap. 83. 

During the extraction procedure a partial racemisation takes place. The racemate of L-hyoscyamine is atropine. The pharmacologically active isomer is L-hyoscyamine, which has double the activity of the racemic atropine. L-hyoscyamine is used for the inhibition of gastric secretion in cases of gastric and duodenal ulcer. 

L., family Solanaceae, which is a perennial herbaceous plant, about one metre high, growing in Central Europe, but nowadays cultivated in former Jugoslavia, Hungary, Poland, China and India. The content of total alkaloids should be 0.35% according to the European Pharmacopoeia 75% of this content is L-hyoscyamine, the rest is mainly atropine, which is formed during the drying process. Both extract and isolated pure substances are used clinically. 

STRAMONIUM LEAF, Stramonii folium is the dried leaf of Datura stramonium X., family Solanaceae, with violet flowers and spiny capsule. Originally from Central America it is now spread globally in warm regions. The alkaloid content is 0.2-0.6%, with L-hyoscyamine and L-scopolamine found in the ratio 2 1 in mature plants. 

For the extraction of L-hyoscyamine, Egyptian henbane, Hyoscyamus muticus, is used, owing to its high alkaloid content 0.5-1.5%. 

HENBANE Hyoscyamus nipier, L., Family Solanaceae, grows on cultivated farmland. The whole plant is poisonous, mainly the seeds due to the presence of L-hyoscyamine, atropine and scopolamine. The symptoms of poisoning are the same as for Belladonna. 

R Virtanen, et al. Radioimmunoassay for atropine and L-hyoscyamine. Acta Phar-mac Toxicol (Copenh) 47 208, 1980. 

A Martinsen, et al. Comparison of radioimmunoassay and capillary gas chromatography in the analysis of L-hyoscyamine from plant material. Phytochem Anal 2 163, 1991. 

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