What is the difference between esters and amides

Procaine is a local anesthetic drug of the amino ester group. It is used primarily to reduce the pain of intramuscular injection of penicillin, and it is also used in dentistry. Owing to the ubiquity of the trade name Novocain, in some regions, procaine is referred to generically as novocaine. The addition of ammonia NH 3 to a carboxylic acid forms an amide , but the reaction is very slow in the laboratory at room temperature.

Water molecules are split out, and a bond is formed between the nitrogen atom and the carbonyl carbon atom. In living cells, amide formation is catalyzed by enzymes. The resulting formation of ester is called Fischer esterification. Esters can also react with amines or ammonia to form amides. This reaction doesn't involve acid catalysis, so the first step is nucleophilic attack at the carbonyl carbon.

Proton transfer follows and loss of the alcohol portion of the ester. Most recent answer. Convert ester to amide in one step by fusing an ester with solid urea at to deg. Carboxylic esters are reduced give 2 alcohols, one from the alcohol portion of the ester and a 1 o alcohol from the reduction of the carboxylate portion. Esters are less reactive towards Nu than aldehydes or ketones.

Solubility in water The small esters are fairly soluble in water but solubility falls with chain length. The reason for the solubility is that although esters can't hydrogen bond with themselves, they can hydrogen bond with water molecules. The strongest numbing cream that is used by dermatologists is a triple anesthetic cream. BLT cream is the most frequently requested skin numbing cream at our compounding pharmacy. Esters include benzocaine, chloroprocaine, cocaine, procaine, proparacaine, and tetracaine.

The amides include articaine, bupivacaine , levobupivacaine, dibucaine, etidocaine, mepivacaine, prilocaine, ropivacaine, and finally, lidocaine. While there are many drugs that can be used intravenously to produce anesthesia or sedation, the most common are: Barbiturates.

Because polar or electrically charged chemical species cannot cross biological membranes, most of the anesthetic drugs penetrates slowly or poorly in the target tissue affected by inflammation or infection.

Cetacaine Topical Anesthetic benzocaine, aminobenzoate and tetracaine is a topical anesthetic used on mucosal membranes to suppress the gag reflex, control pain and ease discomfort during dental and medical procedures. In dental surgery, in which small volumes are injected, concentrations of The names of each locally clinical anesthetic have the suffix "-caine".

Most ester LAs are metabolized by pseudocholinesterase, while amide LAs are metabolized in the liver. Infiltration anesthesia is accomplished with administration of the local anesthetic solution intradermally ID , subcutaneously SC , or submucosally across the nerve path that supplies the area of the body that requires anesthesia. Local anaesthetics are categorised into two different classes based on their structure: para-aminobenzoic acid PABA —based anaesthetics known as esters and non-PABA-based anaesthetics are termed amide local anaesthetics [1].

Ester local anaesthetics include: Benzocaine. What is the difference between amide and ester? Category: sports bodybuilding. Local anesthetics are either amide -based or ester -based. They all have a common core structure of an aromatic right, a tertiary amine, and an alkyl chain. Ester local anesthetics undergo rapid hydrolysis by plasma pseudocholinesterases and to a lesser extent in the liver with resulting pharmacologically inactive metabolites.

However, para-aminobenzoic acid is one of the metabolites that has been associated with allergic reactions in a small percentage of patients. Cerebrospinal fluid lacks the pseudocholinesterase enzyme, so ester local anesthetics administered intrathecally will persist until they have been absorbed by the bloodstream. Patients with atypical plasma pseudocholinesterase are at increased risk for toxic side-effects because of impaired metabolism.

Plasma pseudocholinesterase activity may also be decreased in patients with liver disease or those taking certain chemother-apeutic drugs. Cocaine is the only ester local anesthetic not metabolized in the plasma; rather it undergoes significant liver metabolism.

Amide local anesthetics undergo enzymatic degradation in the liver, which in general is much slower than ester hydrolysis. Patients with decreased liver function e. The amide local anesthetics are not metabolized to para-aminobenzoic acid, and allergic reactions are extremely rare. However, solutions of these drugs may contain preservatives paraben family, whose structure is similar to para-aminobenzoic acid or additives sodium bisulfite that are the frequent culprits of adverse reactions.

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