159581-87-0Relevant articles and documents
Studies on Rubia Akane (RA) derivatives. Part 10. Backbone transformation of RA-VII, an antitumour cyclic hexapeptide, through thionation. X-ray crystal structure of [Tyr-3-ψ(CH2NH)-Ala-4]RA-VII
Hitotsuyanagi, Yukio,Matsumoto, Yuji,Sasaki, Shin-Ichi,Suzuki, Jin,Takeya, Koichi,Yamaguchi, Kentaro,Itokawa, Hideji
, p. 1749 - 1755 (1996)
RA-VII 1 was thionated with Davy reagent methyl 6 or Davy reagent p-tolyl 7 to afford novel thionopeptides, [Tyr-6-ψ(CS-NH)-D-Ala-1]RA-VII 8, [D-Ala-1-ψ(CS-NH)-Ala-2; Tyr-3-ψ(CS-NH)-Ala-4]RA-VII 9 and [Ala-2-ψ(CS-NH)-Tyr-3; Tyr-3-ψ(CS-NH)-Ala-4]RA-VII 10 in addition to known analogues [Tyr-3-ψ(CS-NH)-Ala-4]RA-VII 4 and [Tyr-3-ψ(CS-NH)-Ala-4; Tyr-6-ψ(CS-NH)-D-Ala-1]RA-VII 5. Thionopeptide 4 was reduced with nickel borohydride to give reduced peptide 11. An X-ray analysis and an NMR study revealed that compound 11 adopts a different conformation within the 18-membered-ring moiety from the predominant solution conformation of peptide 1 and of thionopeptides 4, 5, 8-10, which would explain the loss in activity of compound 11.
Studies on Rubia akane (RA) Derivatives. Part 7. Thioamide Analogues of RAs: Antitumour Cyclic Hexapeptides
Hitotsuyanagi, Yukio,Suzuki, Jin,Matsumoto, Yuji,Takeya, Koichi,Itokawa, Hideji
, p. 1887 - 1890 (2007/10/02)
RA-VII 3, RA-VII 4, RA-V 7 and RA-X methyl ester 8 have been prepared from corresponding RAs, and they showed more promising in vitro antitumo