Product Overview

Fmoc-Lys(Boc)-OH (CAS 71989-26-9; catalog AS0890) is an Fmoc-protected L-lysine building block with a Boc-protected side-chain epsilon-amino group. It is used to incorporate Lys into peptides assembled by Fmoc solid-phase synthesis. The alpha-carboxyl group remains available for coupling, while Boc masks the additional primary amine during chain elongation.

Quality Specifications and Ordering

Purity: Alan Scientific supplies Fmoc-Lys(Boc)-OH at >99% purity.

Catalog pack sizes: 25 g, 100 g, 500 g, and 1 kg.

Quality documentation: See Product Documents below for lot-specific COA request details. Review the analytical methods and results reported for the supplied batch.

Quotation: Email [email protected] with AS0890, the pack size, total quantity, delivery destination, and required date. Confirm availability and dispatch lead time before ordering.

State whether the material is for native Lys incorporation or a site-specific modification route. Select any selectively removable protection separately where the route requires it.

Boc Protection for Native Lysine Incorporation

The Fmoc group is removed during routine basic deprotection cycles, while Boc remains on the side chain. A compatible final acidic cleavage and deprotection releases the lysine epsilon-amine. This arrangement is suited to routes requiring native lysine after global deprotection.

Applications include Lys-containing research peptides, sequence-defined libraries, and analogue studies involving amino-side-chain length or charge. Properties of the fully deprotected peptide should not be assigned directly to the protected starting material.

Selecting a Route for Site-Specific Lysine Labeling

Boc is not a universal solution when one chosen lysine side chain must be exposed while the peptide remains resin-bound and other acid-labile groups remain protected. Such projects may require a selectively removable side-chain protection, chosen together with the linker, label, and order of synthesis steps.

After global deprotection, a peptide containing several lysines and a free N-terminus may present multiple reactive amines. Adding a dye, biotin, or lipid at that stage does not automatically produce a single positional isomer. Define the intended attachment site before synthesis rather than relying on the presence of a lysine residue alone.

For attachment-site selection and protection planning, compare N-terminal versus lysine side-chain fluorescent labeling before choosing the lysine building block.

Product Documents

A Safety Data Sheet (SDS / MSDS) is available for this product to support laboratory handling, storage and safety assessment.

MSDS_Fmoc-Lys-Boc-OH_AS0890

Certificates of Analysis are batch-specific. Please contact us to request a COA, and we will provide it by email.

Frequently Asked Questions

What should I include in a quotation request for a Lys-rich peptide library?

List AS0890, the combined quantity required across the library, and your preferred catalog pack size: 25 g, 100 g, 500 g, or 1 kg. Identify any Lys positions requiring selective modification; those positions may need a different protection strategy rather than more Lys(Boc).

Can Lys(Boc) usually be exposed selectively without global acidic deprotection?

Not as a general rule. Compatibility depends on every protection and the resin linker; selective labeling often calls for a different side-chain protection strategy.

Does a peptide with several lysines automatically give one labeled product?

No. Multiple unprotected amines can compete. Site-specific labeling requires a route that controls which amine is accessible during conjugation.

Research Use Only

For research use only. Not for human or veterinary use.