Thionation of segetalins A and B, cyclic peptides with estrogen-like activity from seeds of Vaccaria segetalis

Bioorg Med Chem. 1997 Mar;5(3):631-6. doi: 10.1016/s0968-0896(97)00001-1.

Abstract

Thionation of estrogen-like active cyclic peptides, segetalins A (1) and B (2), with Lawesson's reagent provided each two thiosegetalins; thiosegetalin A1 [Gly-1-psi(CS-NH)-Val-2; Trp-5-psi (CS-NH)-Ala-6]segetalin A, thiosegetalin A2 [Gly-1-psi(CS-NH)-Val-2; Ala-6-psi(CS-NH)-Gly-1]segetalin A, thiosegetalin B1 [Gly-1-psi (CS-NH)-Val-2; Ala-3-psi(CS-NH)-Trp-4]segetalin B, and thiosegetalin B2 [Gly-1-psi(CS-NH)-Val-2; Trp-4-psi(CS-NH)-Ala-1]segetalin B. Thiosegetalin A2 only showed estrogen-like activity against ovariectomized rats. On the basis of their conformations analysed by NMR experiments, the backbone conformation was considered to play an important role in estrogen-like activity for segetalins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Estrogens / chemistry*
  • Estrogens / pharmacology
  • Female
  • Magnetic Resonance Spectroscopy
  • Organ Size / drug effects
  • Ovariectomy
  • Peptides, Cyclic / chemistry*
  • Peptides, Cyclic / pharmacology
  • Protein Conformation
  • Rats
  • Seeds / chemistry*
  • Sulfhydryl Compounds*
  • Uterus / drug effects

Substances

  • Estrogens
  • Peptides, Cyclic
  • Sulfhydryl Compounds
  • segetalin A
  • segetalin B