Synthesis of a tubugi-1-toxin conjugate by a modulizable disulfide linker system with a neuropeptide Y analogue showing selectivity for hY1R-overexpressing tumor cells

• Rainer Kufka,
• Robert Rennert,
• Goran N. Kaluđerović,
• Lutz Weber,
• Wolfgang Richter and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2019, 15, 96–105, doi:10.3762/bjoc.15.11

• tubugi-1–NPY conjugate), and native tubulysin A as reference were investigated by in vitro cell viability and proliferation screenings. The tumor cell lines HT-29, Colo320 (both colon cancer), PC-3 (prostate cancer), and in conjunction with RT-qPCR analyses of the hY1R expression, the cell lines SK-N-MC

• triple-negative breast cancer MDA-MB-468 cells. Keywords: drug targeting; neuropeptide Y; PDC; peptide–drug conjugate; targeted tumor therapy; tubugi; tubulysin A; Ugi reaction; Introduction Until recently, the medication of tumor diseases was primarily based on more or less unspecific

• well as a peptide–tubulysin A conjugate [K4(C(TubA)-βA-),F7,P34]-pNPY – representing a comparable PDC – compared to wildtype pNPY for their binding affinities at the NPY Y1 receptor subtype. While [F7,P34]-pNPY (IC50 = 1.3 nM) showed a comparable binding affinity as pNPY (IC50 = 1.8 nM), the Y1