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  • 157260 - 1-Hydroxybenzotriazole hydrate

157260 Sigma-Aldrich

1-Hydroxybenzotriazole hydrate

wetted with not less than 14 wt. % water, 98%

Synonym: HOBt Hydrate

  • CAS Number 123333-53-9

  • Empirical Formula (Hill Notation) C6H5N3O · xH2O

  • Molecular Weight 135.12 (anhydrous basis)

  •  Beilstein/REAXYS Number 4515

  •  EC Number 219-989-7

  •  PubChem Substance ID 24849666

  •  NACRES NA.22



Related Categories Active Esters/Additives, Chemical Biology, Chemical Synthesis, Coupling, Peptide Coupling,
Quality Level   200
assay   98%
quality   synthesis grade
application(s)   peptide synthesis: suitable
mp   155-158 °C (lit.)
SMILES string   [H]O[H].On1nnc2ccccc12
InChI   1S/C6H5N3O.H2O/c10-9-6-4-2-1-3-5(6)7-8-9;/h1-4,10H;1H2



25, 100, 250 g in glass bottle


Additive used in oligonucleotide couplings and in racemization-free peptide couplings.

Safety & Documentation

Safety Information

Signal word 
Hazard statements 
Precautionary statements 
Supplemental Hazard Statements 
EUH001 - EUH044
UN3474 - class 4.1 - PG 1 - 1-Hydroxybenzotriazole, monohydrate
WGK Germany 


Certificate of Analysis (COA)

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Certificate of Origin (COO)

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Frequently Asked Questions

Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
How do I find price and availability?
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
What is the Department of Transportation shipping information for this product?
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
Why is Product 157260, Hydroxybenzotriazole hydrate wet?
Hydroxybenzotriazole hydrate is a solid that is explosive when dry. Our specification for this product is >14% water.
Can Product 157260, Hydroxybenzotriazole hydrate, be dried?
Drying hydroxybenzotriazole hydrate should not be attempted because of its explosive nature.
How isProduct 157260, Hydroxybenzotriazole hydrate, shipped?
Hydroxybenzotriazole hydrate can not travel be sea or air. It is typically shipped by truck.
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711489 1-Hydroxybenzotriazole hydrate, wetted with not less than 20 wt. % water, 97%

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