1-HYDROXY-7-AZABENZOTRIAZOLE

PRODUCT IDENTIFICATION

CAS NO. 39968-33-7

1-HYDROXY-7-AZABENZOTRIAZOLE

EINECS NO.  
FORMULA C5H4N4O
MOL WT. 136.11

H.S. CODE

 

TOXICITY

 
SYNONYMS HOAt; 3H-[1,2,3]-Triazolo[4,5-b]pyridin-3-ol;
SMILES

 

CLASSIFICATION

COUPLING REAGENTS /

PHYSICAL AND CHEMICAL PROPERTIES

PHYSICAL STATE yellow crystalline powder
MELTING POINT 211 C
BOILING POINT 175 C (Decomposes)
SPECIFIC GRAVITY  
SOLUBILITY IN WATER

Soluble

pH  
VAPOR DENSITY

 

AUTOIGNITION

 

NFPA RATINGS

Health: 1; Flammability: 1; Reactivity: 0

REFRACTIVE INDEX

 
FLASH POINT

 

STABILITY Stable under ordinary conditions. Moistur -sensitive.

GENERAL DESCRIPTION & APPLICATIONS

Carbodiimides are a group of organic compounds which have the resonance formula  N=C=N. Carbodiimide is formed by dehydration of urea or from thiourea. Carbodiimides are readily reacts with various form of amines and hydroxyl functional groups. Carbodiimides are used as dehydration agents and as activating agent of carboxylic acids to form esters or amides. The disubstituted carboxyl activating agents are used for crosslinking proteins to nucleic acids and formation of immunoconjugates in peptide synthesis. N,N'-dicyclohexylcarbodiimide (DCC) is one of the most common peptide coupling agents. It is a low melting point waxy solid; insoluble in water but highly soluble in common organic solvents like acetonitrile dichloromethane, dimethylformamide, and tetrahydrofuran. DCC is a potent allergen. N,N'-diisopropylcarbodiimide (DIC) is an alternative to DCC, DIC is a liquid and is not an allergen. 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) is a water-soluble activating agent for amide bonding with primary amines. It also activates phosphate groups. Typically, it is utilized in the pH range 4.0-6.0 without buffers. In particular, amine and carboxylate buffers should be avoided. Carbodiimides are so active and cause racemization of the amino acid. Active esters are less reactive and less in danger of racemization. 1-Hydroxybenzotriazole (HOBt) and 1-hydroxy-7-aza-benzotriazole (HOAt) are substances that react with the O-acylurea to form active esters. HOAt is a condensation additive in peptide synthesis. It efficiently speeds up coupling process, reduces the loss of chiral integrity, and provides a visual indication (yellow to colorless) of the reaction course. Other active esters exit as non-nucleophilic anionic salts of uronium or phosphonium such as O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate(HBTU), O-(7-Azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU), (Benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate (PyBOP).

SALES SPECIFICATION

APPEARANCE

yellow crystalline powder

ASSAY

99.0% min
MELTING POINT 211 C
TRANSPORTATION
PACKING

 

HAZARD CLASS  
UN NO.  
OTHER INFORMATION
Hazard Symbols: XI, Risk Phrases: 36/37/38, Safety Phrases: 24/25
Price:
Click to open the table

 

Click to close the table