Anticholinergics synthetic

Quaternary anticholinergics - Synthetic or semisynthetic derivatives structurally related to the belladonna alkaloids, they are poorly and unreliably absorbed orally. Because they do not cross the blood-brain barrier, CNS effects are negligible. Duration of action is more prolonged than alkaloids. 

Over the course of the past few decades, a number of synthetic atropine-like substances with more spasmolytic and less anticholinergic action and causing fewer side effects have been used clinically in treating stomach ulcers, pylorospasms, and hyperperistaltics. 

Ipratropium Atrovent HFA, Atrovent Nasal) [Bronchodilotor/ Anticholinergic] Uses Bronchospasm w/ COPD, rhinitis, rhinorrhea Action Synthetic anticholinergic similar to atropine antagonizes acetylcholine receptors, inhibits mucous gland secretions Dose Adults Feds >12 y. Nebuliza-tion 500 meg in 2.5-3.0 mL NS Feds. Nebulization 125-250 meg in 2.5-3.0 mL NS Caution [B, +/-] w/ inhal insulin Contra Allergy to soya lecithin/related foods Disp HFAmet-dose inhal 18 meg/dose inhal soln 0.02% nasal spray 0.03,... 

The synthesis of optically active diaryl methanols 27 is of particular synthetic value, since their core structure represents a molecular scaffold which is relevant to numerous biologically active compounds and pharmaceuticals possessing an-tihistaminic, anticholinergic, local-anesthetic, and laxative properties. Examples include neobenodine 28, orphenadrine 29, and carbinoxamine 30 [31]. 

The prototypical antimuscarinic anticholinergic drug is atropine (Fig. 19-2). Atropine is a naturally occurring substance that can be obtained from the extract of plants such as belladonna and jimsonweed. Other natural, semisynthetic, and synthetic antimuscarinic anticholinergic agents have been developed that are similar in structure or function to atropine. 

Atropine and scopolamine, which are obtained from belladonna alkaloids, as well as other synthetic anticholinergic drugs, inhibit the actions of acetylcholine and cholinomimetic drugs at muscarinic receptors in smooth muscles, heart, and exocrine glands. In addition to these peripheral... 

In the past 40 years a wide variety of synthetic and semi-synthetic anticholinergic agents have been developed for their selectivity in blocking muscarinic receptors in the brain (see Figure 13.8 for the structure of some... 

Drug treatments include sympathomimetic stimulants, anticholinergics, tricyclic antidepressants and synthetic antidiuretics. Of these, imipramine and desmopressin have been found to be the most effective. 

Tiotropium is a QTA representing a synthetic ester of N-methylated scopine (Fig. 1). This drug is clinically used as anticholinergic long-acting bronchodilator applied once daily as aerosolized solution to treat airway diseases such as COPD. Tiotropium is considered as a selective inhibitor of MR subtype Ml and M3 thus not enhancing mucus production [31]. 

A report of three cases (126) has suggested that central cholinergic overactivity is implicated, and that atropine sulfate 3 mg/day or synthetic anticholinergic agents (such as benzatropine mesylate 4 mg/day) ameliorate withdrawal symptoms within a few hours. The authors suggested that this technique may be especially useful in patients in whom tricyclic antidepressants must be abruptly withdrawn because of allergic or idiosyncratic reactions. 

Anticholinergic drugs can cause vivid and sometimes exotic hallucinations and this has led to their misuse. Plants containing atropine and related substances were used in witches brews in the Middle Ages to conjure up the devil, but even synthetic tertiary amines given in eye-drops and depot plasters containing atropine (SEDA-13, 114) have caused hallucinations. Postoperative confusion... 

Shader, R. I., and Greenblatt, 0. J. 1972 Belladonna alkaloids and synthetic anticholinergics. Uses and toxicity. 

Sarin, and neostigolne) co Increase their ouseular strength, with the synthetic anticholinergic compounds and comparing the results of such treatment with those of similar administrations of atropine. Some normal volunteers also were used In this sort of research. 

Bornaprine, a synthetic quaternary ammonium compound, has been used as an anticholinergic drug in treating Parkinson s disease (1). Its adverse effects are those characteristic of the anticholinergic drugs. 

The tropane alkaloids in Mandragora species are powerful anticholinergic agents and can cause peripheral symptoms (for example blurred vision, dry mouth) and central effects (for example drowsiness, delirium) (15). They can potentiate the effects of synthetic drugs with similar pharmacological activity. 

Ipratropium bromide is a synthetic, anticholinergic compound that produces bronchodilatation. 

Another important feature in many of the synthetic anli-chulincrgics used as antispasmodics is that they contain a quaternary nitrogen, presumably to enhance activity. The initial. synthetic quaternary compound mcthantheline bromide has served as a forerunner for many others. Thc.se compounds combine anticholinergic activity of the antimuscar-inic type with some ganglionic blockade to reinfoax the parasympathetic blockade. Formation of a quaternary ammonium moiety, however, introduces the pu.ssibility of blockade of voluntary synapses (curariform activity) this can become evident with sufficiently high doses. 

As a class, anticholinergics include the antihistamines, atropine and homatropine anti-Parkinsonian agents like benzotropine, procyclidine, and trihexyphenidyl the antimuscarinics of which atropine is the prototype and antispasmodics like dicyclomine and oxybutymin. Most antimuscarinics are amino-alcohols or their derivatives (usually esters or ethers), aminoamides, or other amines. Antimuscarinics can be divided into two groups. These are the naturally occurring alkaloids and their semisynthetic derivatives like atropine, homatropine, scopolamine, and hyoscyamine and the synthetic amine compounds such as anisotropine, dicyclomine, and ipratropium. 

The structure of atropine has been the basis for a large number of synthetic anticholinergic agents. However, no significant changes have been made to affect the "ester-complex" grouping because of atropine-like properties. Another probable consideration is that it is far... 

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