EN
Linear and cyclic hymenistatin I (HS I) analogues with dipeptide segments Ile2 -Pro3 , Pro3 -Pro4 and Val6 -Pro7 replaced by their tetrazole analogues Ile2-Ψ[CN4]-Ala3 , Pro3 -Ψ[CN4]-Ala4 and Val6 -Ψ[CN4]-Ala7 were synthesized by the solid phase peptide synthesis method and cyclized with the TBTU and/or HATU reagent. The peptides were examined for their immunosuppressive activity in the lymphocyte proliferation test (LPT).