What is tetrazole used for?
Tetrazole, which is usually used as the bioisoster of carboxylic acid, is metabolically stable to many of the biological transformations that the functionality of carboxylic acid is susceptible to in the liver [2].
Which among three isomers of tetrazole is Nonaromatic?
Structure and bonding In the gas phase, 2H-tetrazole dominates. These isomers can be regarded as aromatic, with 6 π-electrons, while the 5H-isomer is nonaromatic.
Why is tetrazole an acid?
The presence of free N-H causes the acidic nature of tetrazoles and forms both aliphatic and aromatic heterocyclic compounds. Heterocycles of tetrazoles can stabilize the negative charge by delocalization and show corresponding carboxylic acid pKa values.
What is the synthesis of tetrazole?
Synthesis of tetrazoles. An organocatalyst, 5-azido-1-methyl-3,4-dihydro-2 H -pyrrolium azide, generated in situ from N -methyl-2-pyrrolidone (NMP), sodium azide, and trimethylsilyl chloride, enables the formation of tetrazoles by cycloaddition of sodium azide with organic nitriles under neutral conditions and microwave heating.
What is the role of diphenyl phosphorazidate in tetrazole synthesis?
In a synthesis of tetrazoles from amides, diphenyl phosphorazidate or bis ( p -nitrophenyl) phosphorazidate act as both the activator of amide-oxygen for elimination and azide source. Various amides were converted into 1,5-disubstituted and 5-substituted 1 H -tetrazoles in good yields without the use of toxic or explosive reagents.
What is the delocalization energy of tetrazole?
The delocalization energy in tetrazole is 209 kJ/mol. 1 H -Tetrazole and 5- (benzylthio)-1 H -tetrazole (BTT) are widely used as acidic activators of the coupling reaction in oligonucleotide synthesis. ^ Satchell, Jacqueline F.; Smith, Brian J. (2002).
Are there any drugs that are tetrazoles?
There are several pharmaceutical agents which are tetrazoles. Tetrazoles can act as bioisosteres for carboxylate groups because they have similar pKa and are deprotonated at physiological pH. Angiotensin II receptor blockers — such as losartan and candesartan, often are tetrazoles.