129980-23-0 CP-Cct L-Tryptophan, N-((1-(2-carboxy-4-phenylbutyl)cyclopentyl)carbonyl)- N-((1-(2-Carboxy-4-phenylbutyl)cyclopentyl)carbonyl)-L-tryptophan N-(1-(2-Carboxy-4-phenylbutyl)cyclopentylcarbonyl)tryptophan