Class (42) Solanecous Alkaloids and Analogous | Atropine, Hyoscyamines | Medicinal Chemistry 01
Download the "Solution Pharmacy" Mobile App to Get All Uploaded Notes, Model Question Papers, Answer Papers, Online Tests and other GPAT Materials - https://play.google.com/store/apps/de... Solution Pharmacy will cover this syllabus of medicinal chemistry 01 for B.Pharmacy 4th semester Unit 03 - (01) Cholinergic neurotransmitters – Biosynthesis and catabolism of acetylcholine (02) Cholinergic receptor and distribution of cholinergic receptors like muscarinic and nicotinic (03) Parasympathomimetic agents – SAR of parasympathomimetic agents (04) Direct-acting agents – acetylcholine, carbachol, bethanechol, methacholine, pilocarpine, (05) Indirect acting/Cholinesterase inhibitors (Reversible and irreversible) - physostigmine, neostigmine, pyridostigmine, edrophonium chloride, tacrine hydrochloride, ambenonium chloride, isofluorphate, Echothiopate iodide, parathion, malathion. (06) Cholinesterase reactivators – Pralidoxime chloride (07) Cholinergic blocking agents – SAR of cholinolytic agents (08) Solanaceous alkaloid and analogous – Atropine sulphate, hyoscyamines sulphate, scopolamine hydrobromide, homatropine hydrobromide, Ipratropium bromide. (09) Synthetic cholinergic blocking agents – tropicamide, cyclopentolate hydrochloride, aclidinium bromide, dicyclomine hydrobromide, Glycopyrrolate, Methantheline bromide, propantheline bromide, Solanaceous alkaloid and analogous Naturally occurring antimuscarinics were alkaloids found in the family Solanaceae, including Atropa belladonna, Hyoscyamus niger and Datura stramonium. They were used as deadly poison and pupil-dilating cosmetics. While curare, the naturally occurring antinicotinics derived from Chondrodendron and Strychnos, was a poison used by South American Indians for hunting. (−)-Hyoscyamine, isolated as atropine, and scopolamine are the two alkaloids that have found the widespread clinical applications. A. Atropine sulphate Properties and Uses: 1. Atropine is the tropic acid ester of tropine and is marketed as the sulfate salt. 2. The naturally occurring alkaloid, (−)-hyoscyamine, undergoes base-catalyzed racemization during isolation from plants of the Solanaceae to give (±)- hyoscyamine or atropine. 3. It was the first compound shown to block the effects of muscarine and electrical stimulation of the parasympathetic nervous system, hence it is the prototype of antocholinergic drugs. 4. Atropine sulfate has a number of clinical uses; two of the most common are treatment of bradycardia and as a preoperative agent to reduce secretions before surgery. 5. Its use for management of parkinsonism has been supplanted by newer agents with fewer peripheral side effects. B. Scopolamine hydrobromide Properties and Uses: 1. Scopolamine, another Solanaceous alkaloid, is chemically and pharmacologically similar to atropine. 2. Scopolamine is the generic name given to (−)- hyoscine, the naturally occurring alkaloid. 3. Scopolamine is marketed as the hydrobromide salt, because it is less deliquescent than some of its other salts. 4. Interestingly, scopolamine is a CNS depressant at usual therapeutic doses, whereas atropine and other antimuscarinic agents are CNS stimulants. 5. It has been used for the treatment of uveitis, iritis, and parkinsonism, but its most widespread use is for the treatment of motion sickness. 6. For this indication, scopolamine is used in a transdermal patch applied to the skin behind the ear and is well-absorbed percutaneously. 7. Plasma levels are observed within 4 hours and peak levels within 24 hours. C. Homatropne Hydrobromide Properties and uses: 1. Structurally related to atropine, It is 10 times less potent than it. 2. Instilled in the eye, it acts in 45–60 min, mydriasis lasts 1–3 days while accommodation recovers in 1–2 days. 3. It is used topically on the ciliary structure of the eye and to affect mydriasis. D. Ipratropium bromide. Properties and uses: 1. It is a semisynthetic derivative of atropine. 2. It is used in inhalation therapy to produce dilation of bronchial smooth muscle for acute asthmatic attacks. 3. It produces broncho-dilation by competitive inhibition of cholinergic receptors bound to the smooth muscles of the bronchioles. E-Mail for official and other work - [email protected] #solutionpharmacy #Pharmacologyclass #Pharmacognosyvideos #GPAT
