Oligonucleotide synthesis reagents

5-Benzylthio-1H-tetrazole (BTT)

CAS21871-47-6

5-Benzylthio-1H-tetrazole (BTT, CAS 21871-47-6) is a tetrazole-based activator for the coupling step of phosphoramidite oligonucleotide synthesis. BTT is more acidic than both 1H-tetrazole and ETT, which shortens coupling times for 2′-O-TBDMS and TOM-protected RNA phosphoramidites. KingPharm supplies BTT for research and manufacturing, with a batch-specific certificate of analysis.

Chemical structure of 5-Benzylthio-1H-tetrazole (BTT)
C8H8N4S · 192.24 g/mol
CAS No.
21871-47-6
Formula
C8H8N4S
Mol. weight
192.24 g/mol
Appearance
White to Off-white Powder

Product Description

5-Benzylthio-1H-tetrazole, commonly known as BTT (also called BMT, 5-benzylmercaptotetrazole), is a tetrazole-based activator used in phosphoramidite chemistry for oligonucleotide synthesis, particularly RNA synthesis.

During the coupling step, BTT protonates the diisopropylamino group of a nucleoside phosphoramidite and forms a reactive tetrazolide intermediate, which then couples with the free 5′-hydroxyl group of the growing oligonucleotide chain.

BTT is more acidic than ETT and 1H-tetrazole (pKa about 4.1, against about 4.3 and 4.9). With 2′-O-TBDMS RNA phosphoramidites, coupling with BTT takes about 3 minutes, while 1H-tetrazole needs 12 minutes or more. BTT also dissolves in acetonitrile up to about 0.44 M, which is higher than 1H-tetrazole.

When evaluating BTT for a process, buyers usually check the assay, the water content, the clarity of a 0.25 M solution in anhydrous acetonitrile, packaging integrity and batch-to-batch consistency.

Chemical Specifications

Identifiers

CAS number 21871-47-6
Product name 5-Benzylthio-1H-tetrazole (BTT)
Chinese name 5-苄硫基四氮唑
IUPAC name 5-benzylsulfanyl-2H-tetrazole
Synonyms 5-Benzylthio-1H-tetrazole; 5-Benzylmercapto-1H-Tetrazole; 5-Benzylmercaptotetrazole; 5-[(Phenylmethyl)Thio]-1H-Tetrazole; 5-[(Phenylmethyl)Thio-1H-Tetrazole; BMT; BTT; 5-(Benzylthio)-1H-Tetrazoel; 5-((Phenylmethyl)Thio)-1H-Tetrazole
Chinese synonyms 5-BTT; 5-苄巯基四氮唑; 5-(苄基硫代)-1H-四唑; 5-苄硫基-1H-四氮唑; 5-苄硫基四唑
Molecular formula C8H8N4S
Molecular weight 192.24 g/mol
MDL number MFCD00068731
PubChem CID 323185
InChIKey GXGKKIPUFAHZIZ-UHFFFAOYSA-N
SMILES C1=CC=C(C=C1)CSC2=NNN=N2

Physical and chemical properties

Appearance White to Off-white Powder
Melting Point 133.0-138.0 ( ℃ )

Applications

BTT is used at the coupling step of solid-phase oligonucleotide synthesis, usually as a 0.25 M solution in anhydrous acetonitrile.

RNA synthesis

BTT activates 2′-O-TBDMS and 2′-O-TOM protected RNA phosphoramidites with shorter coupling times than 1H-tetrazole.

DNA synthesis

BTT can also serve as a general activator for DNA phosphoramidites on automated synthesizers.

Modified oligonucleotides

Its higher acidity suits sterically hindered or modified phosphoramidites that couple slowly with 1H-tetrazole.

Activator solution preparation

Solid BTT lets users prepare activator solutions in-house at the concentration their process requires.

Quality Documentation

The following documents can be provided for 5-Benzylthio-1H-tetrazole (BTT) to support technical evaluation and purchasing. Documents are issued for the specific grade and batch supplied.

  • Certificate of Analysis (COA) Batch-specific test results against the specification.
Request documents

Packaging, Storage & Transport

Storage Temp 室温, 干燥通风,密闭容器 ( ℃ )

Read the current safety data sheet before handling. Packaging can be adapted to the order quantity and destination.

Frequently Asked Questions

How does BTT compare with ETT and 1H-tetrazole?

BTT is the most acidic of the three (pKa about 4.1, against about 4.3 for ETT and 4.9 for 1H-tetrazole). For 2′-O-TBDMS RNA monomers, coupling with BTT takes about 3 minutes, compared with 12 minutes or more with 1H-tetrazole.

At what concentration is BTT usually used?

BTT is usually used as a 0.25 M solution in anhydrous acetonitrile. Keep the solvent dry, because water lowers coupling efficiency.

How should BTT be stored?

Keep BTT tightly sealed in a cool, dry place, protected from moisture and preferably under an inert atmosphere. Follow the storage conditions on the label and SDS.

What is the CAS number of 5-Benzylthio-1H-tetrazole (BTT)?

The CAS Registry Number of 5-Benzylthio-1H-tetrazole (BTT) is 21871-47-6. 5-Benzylthio-1H-tetrazole (BTT) is also known as 5-Benzylthio-1H-tetrazole; 5-Benzylmercapto-1H-Tetrazole; 5-Benzylmercaptotetrazole.

What is the molecular formula and molecular weight of 5-Benzylthio-1H-tetrazole (BTT)?

The molecular formula of 5-Benzylthio-1H-tetrazole (BTT) is C8H8N4S, and its molecular weight is 192.24 g/mol.

What is 5-Benzylthio-1H-tetrazole (BTT) used for?

BTT is used at the coupling step of solid-phase oligonucleotide synthesis, usually as a 0.25 M solution in anhydrous acetonitrile.

Which quality documents are available for 5-Benzylthio-1H-tetrazole (BTT)?

The following documents are available for 5-Benzylthio-1H-tetrazole (BTT): Certificate of Analysis (COA). Contact KingPharm to request the documents for a specific batch.

How can I request a quotation for 5-Benzylthio-1H-tetrazole (BTT)?

Send an inquiry for 5-Benzylthio-1H-tetrazole (BTT) (CAS 21871-47-6) with the required quantity, target specification, destination country and any documentation requirements. KingPharm will confirm availability, packaging, lead time and price.

Request a Quote for 5-Benzylthio-1H-tetrazole (BTT)

Tell us the required quantity, target specification, destination country and any documentation requirements. We will confirm availability, packaging, lead time and price.

Page last reviewed on by Leo Xiao.