(S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-5-((2,2,10,10-tetramethyl-4,8-dioxo-3,9-dioxa-5,7-diazaundecan-6-ylidene)amino)pentanoic acid

for the following products Fmoc-Arg(Boc)2-OH | Fmoc-L-Arg(Boc)2-OH | N-alpha-(9-Fluorenylmethyloxycarbonyl)-N',N''-bis-tert-butyloxycarbonyl-L-arginine | N-Fmoc-N',N''-diBoc-L-arginine and (S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-5-((2,2,10,10-tetramethyl-4,8-dioxo-3,9-dioxa-5,7-diazaundecan-6-ylidene)amino)pentanoic acid