Piperidine → Glu(OtBu)-Arg(Pmc)-Val-Asp(Allyl)-OBzl

Participants

Reaction Steps

To a solution of Fmoc-Glu(OBut)-Arg(Pmc)-Val-Asp(OAllyl)-OBzl (SEQ ID NO: 37) (12.3 g, 10.3 mmol) in 105 mL of dichloromethane is added piperidine (3.5 g, 41.3 mmol) at ambient temperature. The mixture is stirred 2 hours, then diluted with heptane, concentrated to half volume, and left standing in the freezer overnight. The liquor is decanted from the oily residue, which is then taken up in dichloromethane. The solution is washed with 0.5M aqueous citric acid, water, and brine, dried (magnesium sulfate), filtered, and concentrated. The crude solid is triturated twice with heptane and filtered to give 9.0 g of Glu(OtBu)-(L)Arg(Pmc)-Val-Asp(OAllyl)-OBzl as a white powder. (Mcalc 970.2; M+1obsvd 971).

Provenance & Evidence