Organic Chemistry

Hi, I need help on the biosynthesis of the taurine. Please if you can explain the resonance concept of this synthesis

Hi, Can anyone help me with this question. Why does the Lewis et al Modified Bligh & Dyer method (and many more) use vast volumes of solvent >80mL for 500mg of sample for? I have read many articles, including the Folch method, I can't get access to the origional Bligh & Dyer unfortunately, wherein may lie the answer. There seems to be no standard rule to the volumes used/sample mass or volume however I have seen many variations. Having discussed with a chemistry expert, I am biologist with interest more specifically at the molecular and biochemsitry level, the volume has been adjust to max of 25ml/500mg sample. But without any clarification. I can'…

One of the steps in an experiment I have to do is recrystallization from pentane-ether. Does this mean I have to dissolve the product in a mixture of hot pentane and ether mixed together, filter , and then let the solution cool slowly to crystallize out the product? Or does this mean I can use either pentane or ether? Assuming I use a mixture of the two, does 50/50 mixture of the two make sense?

Generally, in organic chemistry, is it advisable and/or necessary to memorize the catalysts of reactions. For example, H2 reacts with alkenes to produce alkanes in the presence of transition metal catalysts. (commonly: Pt, Pd, Ru, Ni). Do these need to be memorized, and how does this apply to other reactions not just reduction of alkenes.

some times mri is with radiotracer or contrast , does mrs sometimes require radio tracer or contrast or something similar? in vivo or laboratory.

Anyone know a good treatment for this for my son?

Hi all, I already have sodium thiocyanate which I can use for the purposes I want potassium thiocyanate (additive in b&w developer to make b&W or colour positive images in a reversal process on photographic film), but potassium thiocyanate gives finer grain. I was wondering how to get to potassium thiocyanate, online the most I can find is a reaction between a thiosulphate and cyanide. So a thiosulphate and potassium ferricyanide in some kind of function may give me what I need? Is it as simple as a 1:1 molar ratio of thiosulphate to ferricyanide? Do I need the potassium salt to be on the thiosulphate side as well? Or only on the ferricyanide side? …

I am doing some scientific research on thiazole chemistry. I have to brominate 1-(2-(pyridin-4-yl)thiazol-5-yl)ethanone to obtain the bromoketone. I've tried this with elemental bromine in carbon tetrachloride(stirring, reflux) and obtained a red powder after vacuum filtration . The problem is that this molecule has to 2 aromatic N atoms and the bromine is actually incorporated into the molecule. The 1HNMR spectra shows that there has no bromination occured. I have tried to brominate it with NBS/CCl4 + 2 drops HCl conc under reflux. TLC shows that the bromination is incomplete. I have to try some other systems like NBS/MeCN or NBS/DMF with an appropriate catalyst. TsOH m…

Hello ! I am doing some research on thiazole chemistry. I have to brominate 1-(2-(pyridin-4-yl)thiazol-5-yl)ethanone to obtain the corresponding bromoketone. I've tried this with elemental bromine in CCl4 (stirring, r.t) and obtained a red powder after vacuum filtration . The problem is that this molecule has to 2 aromatic N atoms and the bromine is actually incorporated into the molecule (probably like in pyridinium tribromide?). The 1HNMR spectra shows that there has no bromination occured. I have tried to brominate it with NBS/CCl4 + 2 drops HCl conc under reflux. TLC shows that the bromination is incomplete. I don't like CCl4 at all-it is toxic and it doesn't wo…

Hello ! I am doing some research on thiazole chemistry. I have to brominate 1-(2-(pyridin-4-yl)thiazol-5-yl)ethanone to obtain the corresponding bromoketone. I've tried this with elemental bromine in CCl4 (stirring, r.t) and obtained a red powder after vacuum filtration . The problem is that this molecule has to 2 aromatic N atoms and the bromine is actually incorporated into the molecule (probably like in pyridinium tribromide?). The 1HNMR spectra shows that there has no bromination occured. I have tried to brominate it with NBS/CCl4 + 2 drops HCl conc under reflux. TLC shows that the bromination is incomplete. I don't like CCl4 at all-it is toxi…

My 15-year-old sister is convinced that 100 Degrees Celcius 'Water Steam(Stuff that comes out of a kettle)' is hotter than 100 Degrees Celcius 'Water' I tried to straighten her up, but she wouldn't believe it. I then tried my last resort: Comparing the question with the 'Which is heavier; A tonne of Bricks or a Tonne of Feathers' question. 100 Degrees is obviously the sane as 100 degrees, and a tonne is obviously the same as a tonne, it would just take alot more feathers. If you want one more question to answer, here is another obvious question: Which is louder; A 88 decibel motor engine, or a 88 decibel scream? Yes, the above question probably cou…

I forgot 1ml DEPC aliquots for around 6 hours at roomtemperature (but they were in the dark) before i put them into the fridge. Now i dont know if i can still use it to set up 0,1% Depc water. Is it already broken down? Thanks a lot!

So if you were given only the reactants side of an equation, how do you go about knowing which is the acid and which is the base? For example, if you were give NH3 + H20 =________, the products can be NH4+ + OH- or NH2- + H30+. How would you know which is a "better" product?

I am pretty good at drawing MO diagrams when they are simple. For instance, I can start from 1s and go up to, say, 2p and draw everything in (e- in proper location). If it said something like, "Draw the MO diagram of N2" or NO- I'd be able to do it very easily. Despite this, I get very confused when it throws in hybrid orbitals. For example, if the question says, "Using an sp3 orbital on carbon and a p orbital on Fluorine, construct the MO energy diagram" I don't understand this, because isn't Fluorine in CH3F also sp3 hybridized? It has 3 lone pairs and a carbon next to it, yeah? "4 groups". But is it asking for a hybridized orbital of the F, or just one of t…

One of my homework problems asks if the picture below is s valid constitutional isomer of c8h14.

I am learning about oxymercuration-demercuration reactions with alkenes and I wanted to know why this reaction occur? I mean why would oxymercuration-deoxymercuration occur compared to it not occurring? Same with hyrdroboration-oxidation. I mean why doesn't direct hyrdration just occur

Currently I am suffering from a liver disease. I can eat diastase + papain tablets for digestion. But when I was doing my B.Sc. we have put one egg in juice of papaya ( containing ) papain. Within 3-4 hours it was dissolved and amino acids were formed in the juice. But how to separate amino acids from the juice ? ( I do not want individual amino acids just a mixture will do ) But papain must be separated for re-use In fact I want to separate carbohydrates and proteins from a food sample. Take an example of soy flour which contains all required amino acids. If I press the beans, oil can be extracted. remaining cake will contain mixture of carbohydrates and proteins. If …

Hello friends! I'm a second year medical student and I could use some help with the following question about biochemistry: Name 2 reasons why glycine is added to glutamate and cysteine in glutathione (GSH). Thank you!

I am trying to understand how and why these reactions differ. I know that the nucleophile should always attach to the less substituted carbon of a double bond in an addition alkene reaction. However, in my textbook, there are two example questions that are confusing me. One example shows a hydrogen as the nucleophile and the other example shows Bromide as the nucleophile. Would this have anything to do with the fact that the Bromide came from a free-radical?

Hello all, How can we quantitate formic acid that an ant has? Do you know how much is it? Can we use quartz crystal microbalance ? I do not have any information about it. Any help will be appreciated.

I was reading a synth that utilizes 4-piperidone Hcl, stating there is no need to isolate as freebase because the reaction is conducted in PTC conditions (TBAB/TEBA). What about 4-piperidone hydrate/ monohydrate Hcl? Does the same advice apply?

do all alkanes have a reaction during combustion? i would really appreciate your help. ) what is the reaction of acetylene with ammoniacal silver nitrate?

___________________________________________________________________________________ i wonder if in this reaction this mechanism can be possible.... i don´t know.. what you think about? ___________________________________________________________________________________

I need to find a commercially available kit/method for cyanide detection. Are there any available that are quantitative such as an ELISA?

Who have used this reagent? Thanks