EP0389180A1 — Peptides and their use in therapy

USPTO Abstract

An octapeptide of the formula: wherein each A₁ and A₂, independently, is H, C₁₋₁₂ alkyl, C₇₋₁₀ phenylalkyl, R₁CO (where R₁ is C₁₋₂₀ alkyl, C₃₋₂₀ alkenyl, C₃₋₂₀ alkynyl, phenyl, naphthyl, or C₇₋₁₀ phenylalkyl), or R₂OCO (where R₂ is C₁₋₁₀ alkyl or C₇₋₁₀ phenylalkyl), provided that when one of A₁ or A₂ is R₁CO or R₂OCO, the other must be H; A₃ is CH₂-A₆ (where A₆ is pentafluorophenyl, naphthyl, pyridyl, phenyl, or o-, m-, or, more preferably, p-substituted phenyl, where the substituent is a halogen, NH₂, NO₂, OH, or C₁₋₃ alkyl); (I) indicates that tyrosine is iodinated on the phenyl ring at its 3 or 5 carbon positions; A₅ is Thr, Ser, Phe, Val, α-aminobutyric acid, or Ile, provided that when A₃ is phenyl, A₁ is H, and A₂ is H, A₅ cannot be Val; and A₇ is Thr, Trp, or β-Nal; or a pharmaceutically acceptable salt thereof.