logging in or signing up reserpine structural elucidation abdulrazzaqM.PHARM Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 2090 Category: Science & Tech.. License: All Rights Reserved Like it (1) Dislike it (0) Added: November 10, 2010 This Presentation is Public Favorites: 2 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript “ Structural elucidation of RESERPINE ” : “ Structural elucidation of RESERPINE ” Evaluation seminar on :- Presented By :- ABDUL RAZZAQ . M.Pharm , Dept. of Pharma.Chemistry. Content:- : Content:- Introduction Constitution of Reserpine Structure of Yobyrine & reserpic acid confirmation Structure of reserpine confirmation by synthesis Introduction:- : Introduction:- Reserpine is the main constituent of Rauwolfia species,perticularly R.serpentina & R.vomitoria. It is mainly used for the treatment of hypertension, headache, tension, asthma & dermatological disorders. Constitution of reserpine:- : Constitution of reserpine:- 1. Molecular formula:- C33H40N2O9 2. Presence of five methoxy groups:- By zeisel method i.e. when treated with HI yields five molecules of methyl iodide indicating the presence of five methoxy groups. 3. Nature of ‘N’ atom:- a) Secondary ‘N’ – Formation of monoacetyl derivative with acetic anhydride indicates secondary ‘N’ . b) Tertiary ‘N’- Reserpine forms quaternary ammonium salts with CH3I that indicating one of ‘N’ is tertiary. : 4. Hydrolysis:- Hydrolysis of reserpine yields mixture of i) Methyl alcohol ii) 3,4,5-trimethoxy benzoic acid iii) Acid (A) of composition : As reserpine does not contain -COOH & -OH groups, hence its hydrolysis product reveal that reserpine is a di-ester. The ester linkage in reserpine has been further confirmed by its reduction with 5. Reduction:- #Structure of Reserpic acid:- : #Structure of Reserpic acid:- a) Molecular formula:- b) Presence of one carboxyl group:- By usual tests e.g. silver salt method c) Presence one –OH group:- Reserpic acid on oxidation yields a ketone that means it has secondary alcoholic group. d) Nature of two methoxy groups:- By zeisels method. e) Nature of two ‘N’ atom:- It shown that it contains two ‘N’ atoms in heterocyclic ring in the form of- i) Secondary ‘N’ ii) Tertiary amino group : f) Reduction of reserpic acid:- On reduction with yields reserpic alcohol. g) Oxidation of reserpic acid:- On oxidation with it gives 4-methoxy N-oxalyl anthranilic acid. Thus one of the methoxyl group is present in meta position to –NH group : h) Fusion with KOH :- When reserpic acid is fused with potash it yields 5-hydroxy isophthalic acid. One of the acidic groups of isophthalic acid must be present in m- position to each other this confirm by the fact that reserpic acid when heated with acetic anhydride yields a gamma lactone. : i) Dehydrogenation:- When methyl reserpate is dehydrogenated with selenium it yields a hydrocarbon of molecular formula - This hydrocarbon is also obtained by dehydrogenation of Yohimbine with selenium & was therefore named as Yobyrine. Structure of Yobyrine:_ : Structure of Yobyrine:_ 1. Molecular formula:- 2. Zinc Distillation:- 3. Oxidation:- When yobyrine is oxidized with permangnate it yields phthalic acid : 4. Condensation with aldehydes:- Yobyrine gives condensation products suggesting the presence of pyridine ring with a methylene substitution adjacent to the nitrogen. On the basis of above facts following structure has been postulated for yobyrine. Synthesis of Yobyrine:- : Synthesis of Yobyrine:- : j) As Yobyrine is formed from reserpic acid it means that reserpic acid may possesses the following types of skeleton structures. k) From the fact 5(g) it follows that one of the methoxyl group is present in m-position to the NH group of indole i.e. on C-11 i.e. Ome is at C-11. : Reserpic acid when dehydrogenated yields 11-hydroxy-16-methyl yobyrine,this may be only formed if –COOH group is present on C-16 From the step (h) it follows that –COOH & -OH group are in m-position to each other but –COOH group is present at C-16 therefore –OH group must be at C-18. : From purely biogenic reasons, the 2nd methoxyl group has been assigned position C-17. On the basis above mentioned facts the structure of reserpic acid may be Structure of Reserpine:- : Structure of Reserpine:- As reserpine is di-ester of reserpic acid, it means that, Synthesis of Reserpine:- : Synthesis of Reserpine:- The structure of reserpine has been confirmed by its synthesis given by Woodward et.al. : Synthesis continue….. Synthesis continue….. : Synthesis continue….. Synthesis continue….. : Synthesis continue….. Synthesis continue….. : Synthesis continue….. Synthesis continue….. : Synthesis continue….. References :- : References :- 1)“ Organic Organic Chemistry of Natural Products ”- by Gurudeep Chatwal ,Vol-I. 2)“ Organic Chemistry ”by I.L.Finar , Vol-II . 3)“Pharmacognosy” by C.K.Kokate , A.P.Purohit , S.B.Gokhale You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.