Product Details

Fmoc-L-Trp(Boc)-OH (CAS 143824-78-6), also known as Nα-Fmoc-N(in)-Boc-L-tryptophan, is the standard Fmoc-SPPS building block for tryptophan with Boc protection on the indole nitrogen. It is part of the Fmoc-tryptophan Boc-indole class. The indole Boc protection keeps active esters and aspartimide-forming reagents from alkylating the electron-rich indole ring during Fmoc-SPPS. It also stops formyl- or acetyl-tryptophan side products from forming during TFA deprotection (if there are no scavengers). Tryptophan is very prone to oxidative degradation, which makes kynurenine, 3-hydroxy-Trp, and oxindole. 

ApiSyn sells Fmoc-L-Trp(Boc)-OH (CAS 143824-78-6) as a pharmaceutical-grade building block and reference standard for therapeutic peptide SPPS.