Hyoscamine

Belladonna contains tropane alkaloids, atropine, hyoscamine, and scopolamine, all... 

Atropine (= Hyoscamine racemate Tropine tropate) (tropane)... 

Muscarinic Acetylcholine receptor (mACh-R) — antagonists Alkaloid Atropine (= d,l-Hyoscamine Tropine ( )-tropate ester) (racemate of hyoscamine)... 

Atropinesterase can also hydrolyze homat-ropine and scopolamine. This enzyme is stereospecific for (5)-(-)-hyoscamine, which is split the more inert isomer is not... 

Esterification of the nitrogenous moiety with tropic acid is a structural type thought to be unique to the Solanaceae family (Evans 1990 Roddick 1991). The major alkaloids are hyoscamine and hyoscine (= scopolamine). Atropine, the racemic form of hyoscamine, generally occurs in trace amounts only. 

Hyoscamine acts on tissue cells innervated by post-ganglionic cholinergic fibres of the parasympathetic nervous system it is antimuscarinic and a parasympathetic depressant. 

Hyoscamine has a spasmolytic effect on bronchial and intestinal smooth muscles. The mydriatic effect (inhibits contraction of iris muscle) is more pronounced than that of atropine. It reduces salivary and sweat gland secretions, controls excess motor activity in the gastrointestinal tract, producing an antidiarrhoeal effect, and... 

Datura contains over 30 tropane alkaloids, mainly hyoscamine and hyoscine, as well as nitrogen oxides of hyoscamine and hyoscine, tigloylmeteloidine and nicotine. It is indicated for asthma, pertussis, muscular spasm and excess salivation in Parkinsonism (Bradley 1992). 

Stramonium is listed in Schedule 1—dangerous poisons and Schedule 2—medicinal poisons (containing 0.25% or less of alkaloids calculated as hyoscamine) of the New South Wales Poisons List in Australia. Exceptions are made in preparations for smoking or burning. 

Fig. 13.6. DESI mass spectrum of Atropa belladonna seeds using methanol water =1 1 as spray solvent. The insets show tandem mass spectra of the protonated alkaloids hyoscamine, m/z 290 and scopolamine, m/z 304. Both protonated alkaloids have the characteristic loss of tropic acid, 166 u, in common. Reprinted from Ref. [13] with permission. The Royal Society of Chemistry, 2005.

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