Penicillamine

Corresponds to β,β-dimethylcysteine or β-mercaptovaline. For an S-protected derivative of deamino-penicillamine please see Q-1610.
The rigidity of disulfide bridges can be increased by replacing Cys by Pen. Pen analogs of enkephalins, RGD-peptides, urotensin and further active peptides with improved potency and/or selectivity have been described.

A-2965	Boc-Pen(Acm)-OH
A-2970	Boc-D-Pen(Acm)-OH
A-3660	Boc-Pen(Mbzl)-OH · DCHA
A-3665	Boc-D-Pen(Mbzl)-OH · DCHA
A-2900	Boc-Pen(Mob)-OH
A-3990	Boc-D-Pen(Mob)-OH
A-3650	Boc-Pen(NPys)-OH
A-3655	Boc-D-Pen(NPys)-OH
A-3550	Boc-Pen(Trt)-OH
A-3555	Boc-D-Pen(Trt)-OH
B-1885	Fmoc-Pen(Acm)-OH
B-1915	Fmoc-D-Pen(Acm)-OH
B-1545	Fmoc-D-Pen(Bzl)-OH
B-2315	Fmoc-Pen(Trt)-OH
B-2320	Fmoc-D-Pen(Trt)-OH
Q-1610	3-(4-Methoxy-benzylsulfanyl)-3-methyl-butyric acid
F-2515	H-Pen-OH
F-4235	H-D-Pen-OH
F-3065	H-Pen(Trt)-OH
F-3070	H-D-Pen(Trt)-OH