Pentobarbital

Ethyl 5 (1 methylbutyl) barbitunc acid (pentobarbital Nembutal)... 

Show by writing a suitable sequence of reactions how you could prepare pentobarbital from diethyl malonate (The structure of pentobar... 

Barbituric acids as their name implies are weakly acidic and are converted to then-sodium salts (sodium barbiturates) m aqueous sodium hydroxide Sometimes the drug is dispensed m its neutral form sometimes the sodium salt is used The salt is designated by appending the word sodium to the name of the barbituric acid—pentobarbital sodium for example... 

Thiourea (H2NCNH2) reacts with diethyl malonate and its alkyl derivatives in the same way that urea does Give the structure of the product obtained when thiourea is used instead of urea in the synthesis of pentobarbital The anesthetic thiopental (Pentothal) sodium is the sodium salt of this product yWhat IS the structure of this compound ... 

Although most anesthetics are achiral or are adininistered as racemic mixture, the anesthetic actions are stereoselective. This property can define a specific, rather than a nonspecific, site of action. Stereoselectivity is observed for such barbiturates as thiopental, pentobarbital, and secobarbital. The (3)-enantiomer is modestly more potent (56,57). Additionally, the volatile anesthetic isoflurane also shows stereoselectivity. The (3)-enantiomer is the more active (58). Further evidence that proteins might serve as appropriate targets for general anesthetics come from observations that anesthetics inhibit the activity of the enzyme luciferase. The potencies parallel the anesthetic activities closely (59,60). 

The potential for normal brain tissue injury is one of the limiting factors in the use of XRT for brain tumors. Pentobarbital is a cerebral radioprotectant in rodent and primate models after single doses, but is associated with significant risks. Of alternative barbiturates, thiopental given to tats receiving 70-Gy (7000-rad) whole-brain irradiation in a single fraction enhances the 30-day survival similarly to pentobarbital, whereas ethohexital and phenobarbital show no radioprotective activity (250). 

Pentobarbital (5-ethyl-5-r-methylbutyl barbituric acid. Nembutal) [76-74-4] M 226.4, m 127 (dec), pKEst(i) 8.0, pKEst(2) 12.7. Soln of the sodium salt in 10% HCl was prepared and the acid was extracted by addition of ether. Then purified by repeated crystn from CHCI3. [Bucket and Sandorfy J Phys Chem 88 3274 1984.]... 

Pentazocine j, 297 2 325 Pentobarbital 1, 268 Pentomone 3, 2T8 PentoxphylTine 466 Pentyl enetetrazole 281 Perazine 1, 381 Pergolide 249 Perlapine 425 Perphenazine 1, 383 Pethidine 1, 300 Phenacaine 19 Phenacemide 1, 95 Phenacetemide Phenacetin 111... 

Pentobarbital, marketed under the name Nembutal, is a barbiturate used i treating insomnia. It is synthesized in three steps from diethyl maionatt Show how you would synthesize the dialkylated intermediate, and then pre pose a mechanism for the reaction of that intermediate with urea to giv pentobarbital. 

The other method used is infusion of intravenous anaesthetics such as propofol, etomidate (for induction) and the barbiturates such as thiopental and pentobarbital. Investigations into the mechanism of anaesthesia have made use of all these compounds in order to identify a common mode of action linked to likely mechanisms within the CNS. 

Short-acting (eg, secobarbital [Seconal], pentobarbital [Nembutal]). The average duration of action of the short-acting barbiturates is 3 to 4 hours. 

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