* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
All peptides were synthesized on a 0.2 mmol scale using manual Fmoc-SPPS chemistry under flow using a 3 minute cycle for each amino acid. Specifically, all reagents and solvents are delivered to a stainless steel reactor containing resins at a constant flow rate using HPLC pump; temperature of the reactor was maintained at 60 °C during the synthesis using water bath. Procedure for each amino acid coupling cycle included a 30 second coupling with 1 mmol Fmoc-protected amino acid, 1 mmol HBTU, and 500 of diisopropyl ethyl amine (DIEA) in 2.5 mL of DMF at a flow rate of 6 mL/min (note that for coupling of cysteine and tryptophan, 190 of DIEA was used to prevent racemization); 1 minute wash with DMF at a flow rate of 20 mL/min; 20 second deprotection with 50percent (v/v) piperidine in DMF at a flow rate of 20 mL/min; and 1 minute wash with DMF at a flow rate was 20 mL/min. After completion of the stepwise SPPS, the resin was washed thoroughly with DCM and dried under vacuum. The peptide is simultaneously cleaved from the resin and side-chain deprotected by treatment with 2.5percent (v/v) water, 2.5percent (v/v) 1 ,2- ethanedithiol (EDT), and 1percent (v/v) triisoproprylsilane in neat trifluoroacetic acid (TFA) for 2 hours at room temperature. The resulting solution containing peptide was evaporated by blowing a stream of nitrogen gas over its surface for 15 minutes, then triturated and washed with cold diethyl ether three times. The obtained gummy-like solid was dissolved in 50percent H20: 50percent acetonitrile containing 0.1percent TFA and lyophilized. These same solvent compositions were used in majority of experiments and will be referred to as A: 0.1percent TFA in H20 and B: 0.1percent TFA in acetonitrile. c. Peptide Purification The crude peptide was dissolved in 95percent A: 5percent B with 6 M guanidinium hydrochloride and purified by semi-preparative RP-HPLC (Agilent Zorbax SB C18 column: 21.2 x 250 mm, 7 mutaueta, linear gradient: 5-50percent B over 90 min, flow rate: 5 mL/min). 1 of each HPLC fraction was mixed with 1 mu^ of alpha-cyano-4-hydroxycinnamic acid (CHCA) matrix in 75percent A: 25percent B, spotted with MALDI, and checked for fractions with desired molecular mass. The purity of fractions was confirmed by analytical RP-HPLC (Agilent Zorbax SB C3 column: 2.1 x 150 mm, 5 muiotaeta, gradient: 0-2 minutes 5percent B, 2-11 minutes 5- 65percent B, 11-12 minutes 65percent B, flow rate: 0.8 mL/min). HPLC fractions containing only product materials were confirmed by LC-MS analysis, combined, and then lyophilized. Peptides synthesized using fast flow-based SPPS and purified by RP-HPLC are listed in Table SI .
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
For Research Only
120K+ Compounds
Competitive Price
1-2 Day Shipping
