 all of us are familiar with many drug molecules. We are talking about pharmaceuticals. These are life saving molecules or life saving materials. Many pharmaceuticals are available which are prepared in organic chemistry level. Similarly, there are many metal containing medicines which can be also life saving. But today we will mainly look at some of the molecules which can be prepared very easily by using our organic chemistry knowledge which we have acquired and ready. Let us look at some of the most famous ones. All of us are familiar with paracetamol, isotropic acidine, naproxen, dinetidine. These are very simple organic molecules and these are prepared by using sometimes one step to up to six or seven step synthesis from readily available material. As you all know, ibuprofen is an algae acid that essentially means that it is a pentator, right? And also it is anti-inflammatory. We will look at it in a moment Paracetamol on the other hand is an algae acid which almost for every purpose, you know, every little bit pain. There are people who use it quite a lot. Sometimes they end up abusing. So please do not use the medicine unless it is prescribed by doctor. Don't take over the counter medicine whenever you feel that something is wrong with you. You can take any of the medicine or I would say no medicine one should take without prescription or without the need which is justified by the doctor. Aspirin once again heavily used, I would say abused maybe to a greater extent. It is analogous as well as anti-inflammatory. All these are available over the counter. That means without prescription from doctor you can get but that doesn't mean that for every little cause or every little pain you should start using medicine. It's a very bad habit which would usually lead to lesser potency in your body, lesser drug resistance or lesser disease resistance in your body. So please do not once again take the medicine without prescription. There is imipramin which is antidepressant. Again these are the medicines one should not take without consulting the doctor. I think in India we need to do better in terms of sale of the medicine. Sometimes lot of medicines are available without proper prescription which need to be stopped and all of us being educated we should try our best to tell people that consuming medicine without proper prescription is something not desirable at all. Chloramphenical it is antimicrobial. We'll see in a moment how it can be molecule. Quite interestingly naproxen which is in effect will also how to prepare with very, very simple. Finally we'll see the synthesis of ranitidine. Let's look at paracetamol synthesis once again paracetamol is an analgesic when spent killer disease. You take paracetamol quite often I believe one of the most used medicines. Synthesis is easier I would say. It takes the four amino phenols which is one of the cheapest molecules you can get in organic laboratory. You react it with acidic and hydride to give paracetamol. One step synthesis, simplest synthesis anyone almost anyone should be able to synthesize it without even knowledge of organic chemistry one can synthesize this paracetamol. It can be prepared in metric non-scale. It has been prepared in huge scale in industry. Things are nice simple. A synthesis which is easier or better than this is difficult to imagine. Of course there are many different approaches one can think of including the availability of the starting material, how to deal with the side product if anything is forming. I think this method that is outlined here is unbeatable. This is the one which is used most often. Let us then look at our next molecule which is aspirin. This is ortho hydroxy benzoic acid also known as salicylic acid. Now the salicylic acid is once again one of the very cheap organic molecules you can find in any organic laboratory. It is not a surprise that therefore by using this salicylic acid, acetic anhydride treatment gives you aspirin and this is the method which is used industrially. I would say there is no need really to look for an alternative method to prepare this molecule. It works beautifully and these reactions are quite powerful to prepare this simple drug that is aspirin. Aspirin is analgesic as well as anti-inflammatory. Let us look at this not so simple molecule Ibuprofen. Ibuprofen synthesis is known till since I guess 1960s. This is one of the even used molecules as you know Ibuprofen for its analgesic as well as anti-inflammatory role. Ibuprofen synthesis has been done by 6 steps in industry starting from 1916. This is a famous boot process. The starting material although I am showing here isobutyl benzene but you can prepare it from benzene, simple benzene you can start with and do a tridal craft reaction, tridal craft, tridal craft alkylation reaction you can do with benzene by using propylene. You take benzene reacted to propylene in presence of aluminium chloride to get the tridal craft alkylated product that is isobutyl benzene. Now this is very cheap to prepare what you do next step is the tridal craft acylation, tridal craft alkylation followed by tridal craft acylase once again by using aluminium trichloride. You do this reaction, double tridal craft reaction on the product with an alkyl as well as acylase. Subsequently you react it with this ethyl chloroacetate in presence of a base sodium ethoxide right. So you deprotonate it and attack it on the ketone to get this epoxide intermediate which then one can hydrolyze to get this branch aldehyde. One can think of preparing this branch aldehyde by many other methods such as if you have an olefin is their branch hydrochromination one can do let's not get into the other possible routes by which you can synthesize this intermediate. This is I think quite an interesting method to prepare it. You prepare this intermediate by this method and no metal metal free so far and you then use this hydroxyl amine to give the aldehyde ring which upon treatment with acetic anhydride the heating condition gives you the corresponding cyan or intermediate. So in the ibuprofen then we can synthesize this ibuprofen in the boot process by following this excellent procedure which is six steps and gives the product in excellent quality. Now if we are looking at so this ibuprofen can be synthesized from the three steps starting from simple benzene. This is known as the boot process that is known since 1960s. It is a very effective process in the industrial preparation of ibuprofen started with boot process. But in the next slide you will see a modified version of this where we find that ibuprofen can be synthesized only in three steps as opposed to the six steps that you have seen in the last slide. Once again here also we start with benzene the simplest possible starting material. We take benzene and we do a Friedelkraft alkylation reaction with propylene to give isobutyl benzene just like in the last case. This Friedelkraft alkylation is followed by Friedelkraft acylation where acyl chloride and aluminium trichloride is reacted with this isobutyl benzene to give this same double Friedelkraft alkylated acylated intermediate. This is the same intermediate as in boot process. If we take this intermediate now in a little bit different sense where we see that this ketone is reduced to the hydroxyl by using hydrogen gas and palladium on charcoal. It is a very effective method therefore although it is the metal mediated process industrially it is still viable and it has been followed subsequently with this secondary alcohol with 10% HCl and CO gas in presence of palladium chloride this triphenyl phosphine complex it is oxidatively added CO inserted and then hydrolysis gives you the ibuprofen. This is quite amazing synthesis simple synthesis in three steps as opposed to the six steps as you have seen in the boot process. This is the first process and it works beautifully industrially it has been used quite a lot. Now you have seen this analgesic you know this ibuprofen which is used quite a lot in regular life it can be done by utilizing this simple methodology as you see in here. The basic difference between these two process has led to this horse process which is more important and it gives the product in useful yield despite having the metal mediated synthesis. Let us look at yet another powerful pharmaceuticals known as imipramine it is antidepressant and it is used quite often. It is one of the best selling antidepressant for some time. Imipramine is synthesized from dibenzygete as you see this tricyclic ring containing organic molecule it is reacted with three dimethyl aminopropyl chloride as you see on the right hand side. It is a simple nucleophilic substitution reaction gives you imipramine in right one step in one step only which is fantastic. Imipramine which is an antidepressant can be synthesized from these two reagents by using this three dimethyl aminopropyl chloride and NH2 to give this product. Now here is yet another exciting drug molecule known as chloramhenicol. Chloramhenicol synthesis is a marvel in synthetic chemistry domain. It is started with a simple material such as this four nitro acetophenone. Chloramhenicol is a famous antimicrobial which is used quite a lot as you can see in here chloramhenicol has this CCl2 motive CHCl2 motive which is important and this is a little bit complex molecule compared to what we have seen previously the synthesis is straightforward simple organic synthesis without any metal mediated process we get this compound. So starting from this four nitro acetophenone we have the bromination reaction rather alpha bromination alpha bromo acetophenone and the para position nitro group which is simple exciting this alpha bromination happens this activated CH bond get brominated and subsequently we have hexamine as well as HCl to do the amination reaction over here and you protect this amine with HCl subsequently acetic anodized treatment give you an acetyl intermediate to protect the amine and then reacting with formaldehyde gives you this alcohol this primary alcohol via the protonation of this carbon center and attacking on the formaldehyde gives you this primary alcohol but if you protect this in acyl group you will get the amino alcohol which you see in here so the deprotection of this in acetyl will give you amino alcohol that is required for the preparation of chloramhenicol but before going back you have to do the reduction of this ketone right so this ketone selective reduction in these cases in presence of nitro as you can see you have a nitro moiety in there and you have a ketone so selective reduction of this ketone can be done by this MPV reduction which utilizes aluminum isopropoxide intermediate compound along with isopropyl alcohol which is a sacrificial donor hydrogen donor hydride donor actually so this reduces this is a mild relatively mild reducing condition to give you the secondary alcohol in presence of nitro this reduction can be occurring to give you this intermediate from where if you deprotect this in acetyl with in presence of HCl and chloroacetic camphor sulfonic acid you get this amino alcohol intermediate from there on it's just one more step as you can see here with this simple reagent you can get the chloramhenicol synthesis so just to come back again for this chloramhenicol synthesis it is 1, 2, 3, 4, 5, 6, 7 steps from a readily available starting material and the simplest possible starting material one can synthesize or one can complete the synthesis of chloramhenicol which is an antimicrobial you start with nitro acetophenone do the bramination convert it to amine protect the amine and then react it with formaldehyde and then you get this secondary alcohol and the keto group that you have over here selectively you need to reduce it in presence of the nitro group so you use MPV reduction procedure subsequently remove you remove the acetyl protection by acid hydrolysis with HCl and camphor sulfonic acid and then you install this final COCHCl2 motive to give you the chloramhenicol which is fantastic molecule if you look at for this sort of antimicrobial synthesis let us look at the next one next one is the naproxen synthesis it is again another beautiful demonstration of what synthetic chemist can achieve by simple organic chemistry beta naphthal is taken which is one of the cheapest and readily available starting material one can get for this naproxen synthesis you start with beta naphthal you brominate of course monobromination is not easy to get it is always end up giving dibromination in the position as shown in here this dibromo of course we do not want one of this bromide that is in here this bromine is removed by NAHSO4 treatment give you this monobrominated beta naphthal derivative protecting this hydroxyl or since in that naproxen you have methoxy group so you install the methoxy group or you protect the phenol with methyl group OLE by using this CH3Cl in presence of a base so you have bromomethoxy beta methoxy naphthalene right which is again quite useful or quite important intermediate from here treatment with magnesium and bromomagnes this ethyl acetate you get this beautiful naproxen molecule which is in resemic form by using this N alkyl glucamine you can resolve it to get the S naproxen it is a NSID non-steroidal anti-inflammatory drugs which is quite popular and used widely in pharmaceutical world again please do not consume the any of these any of these or any other medicine directly without doctors permissions or doctors advice this is the final molecule synthesis for today that is ranitidine ranitidine is an antacid it is used widely worldwide specifically in our country it has been used quite a lot it is prepared only in three steps starting with full furial alcohol once again it is a very cheap starting material for furial alcohol reacting with formaldehyde and dimethyl amine gives you these one five disubstituted furan derivatives one five disubstituted furan derivative and reacting this furan with this aminothiol you get further derived or advanced intermediate which is having a primary amine over there which is nucleophilic enough to attack on this carbon center to give you the complete synthesis of ranitidine once again this is an simple reactions condensate a simple reaction amine formation and attack on the on the on the five position subsequently a further intermediate synthesis to give you the ranitidine this completes a very important medicine pharmaceuticals that is available over the counter and it gives you access to the preparation of this molecule in the shortest possible route only in three steps one can synthesize this molecule to give the desired pharmaceuticals with this I hope you would look for many more synthesis of the simple pharmaceuticals and we will be happy to discuss in future regarding this. Thank you very much. See you later. There is the reference for this work or any of these you can get from the internet as well here is there is the reference for all these synthesis.