What is EDC in organic chemistry?

What is EDC in organic chemistry?

EDC (also called EDAC) is 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride, MW 191.70. DCC is N’, N’-dicyclohexyl carbodiimide, MW 206.32. Carbodiimide conjugation, as with CDI-mediated conjugation, works by activating carboxyl groups for direct reaction with primary amines via amide bond formation.

What is the difference between Hatu and HBTU?

O-(7-Azabenzotriazol-1-yl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU) is similar to HBTU, but reacts faster with less epimerization during coupling. HATU is preferred to HBTU in most rapid coupling protocols. HATU is utilized in the same manner as HBTU.

Which reagent is used for peptide coupling?

Peptide Coupling Agents HOAt, as additives, and HOAt-based peptide coupling reagents, as activators, are used in peptide bond formation reactions both in solution and solid phase synthesis. There are many different types of peptide coupling reagents (e.g., carbodiimides, aminium/uranium salts, and phosphonium salts).

Is EDC soluble in water?

EDC has a high solubility in water (> then 200g/l) and is also soluble in a variety of organic solvents e.g. dichloromethane, tetrahydrofuran and dimethylformamide. Although EDC can be used for reactions in aqueous solution it is usually stored under dry conditions to prevent slow hydrolysis to the corresponding urea.

Is EDC water sensitive?

Handling, Storage, and Precautions: EDC is moisture-sensitive; store under N2 in a cool dry place. It is incompatible with strong oxidizers and strong acids.

How do I prepare for EDC NHS solution?

Protocol

1. Equilibrate the EDC and NHS to room temperature before opening.
2. Prepare 1ml of a 1mg/ml solution of Protein #1 in Conjugation Buffer 1.
3. Add 0.4mg EDC and 0.6mg NHS or 1.1.mg sulfo-NHS and react for 15 minutes at room temperature.
4. Add 1.2µl 2-mercaptoethanol to quench the EDC.

Why is HOBt used?

HOBt is used to produce such activated esters. These esters are insoluble (like the N-hydroxysuccinimide esters) and react with amines at ambient temperature to give amides. HOBt is also used for the synthesis of amides from carboxylic acids aside from amino acids.

What is acid amine coupling?

The amide coupling is a robust and popular reaction used frequently in chemical synthesis. The transformation couples an amine (1) and a carboxylic acid (2) to form an amide (3) (Fig. 1a).

What is amino acid coupling?

Amino acid coupling These coupling reagents react with the carboxyl group to form a highly reactive O-acylisourea intermediate that is quickly displaced by nucleophilic attack from the deprotected primary amino group on the N-terminus of the growing peptide chain to form the nascent peptide bond.

Is TFA a coupling reagent?

m-CPBA/TFA: an efficient nonmetallic reagent for oxidative coupling of 1,2-diarylethylenes.

What is the difference between DCC and EDC?

The key difference between DCC and EDC is that DCC is a cyclic compound, whereas EDC is an aliphatic compound. Another major difference between DCC and EDC is that DCC is insoluble in water while EDC is water-soluble.

What is EDC and NHS?

EDC, in conjunction with NHS allows, for 2-step coupling of two proteins without affecting the carboxyls of the second protein. First, EDC activates carboxyl groups and forms an amine reactive O-acylisourea intermediate that spontaneously reacts with primary amines to form an amide bond and an isourea by-product.

What are peptide coupling reagents used for?

Benzotriazole-based peptide coupling reagents and additives, as activators or additives (Figure 1), are used in peptide bond formation reactions both in solution and solid-phase synthesis. There are many different types of peptide coupling reagents (e.g., carbodiimides, aminium/uranium salts, and phosphonium salts).

What is the racemization of α-during peptide coupling?

During peptide coupling, racemization α- to the carbonyl of what was formerly the carboxylic acid group is a concern, usually through oxazolone formation (see discussion with Figure 7.1 ).

Can iminium salts be used as peptide coupling reagents?

The use of iminium salts as peptide coupling reagents has been extensively explored, and the CIP reagent 12 is useful for couplings involving hindered amino acids, especially in the presence of the additive HOAt <1996JOC3350>.

Is there a substitute for HOBT in peptide coupling?

The nucleus of HOBt is incorporated into some peptide coupling reagents, such as HBTU, HATU, and PYBOP (see Figure 4.17 ), and these reagents should be treated with care appropriate to HOBt. Pfizer researchers and others have examined substitutes for HOBt [85,86,94].