872877-06-0Relevant articles and documents
Synthesis of hydroxyphenylglycine-derived novel poly(silylenevinylenephenyleneethynylene)s
Ueda, Tokiko,Shiotsuki, Masashi,Sanda, Fumio
, p. 3570 - 3579 (2011)
The hydrosilylation polymerization of d-(-)-p-hydroxyphenylglycine-derived diethynyl monomers 1p and 1m with dihydrosilanes Si1 and Si2 was carried out using RhI(PPh3)3 as a catalyst to give optically active novel poly(silylenevinylenephenyleneethynylene)s [(E)-poly(1p-Si1), (E)-poly(1p-Si2), (E)-poly(1m-Si1), (E)-poly(1m-Si2), and (Z)-poly(1p-Si1)] with number-average molecular weights ranging from 2800 to 17,000 in 41-92% yields. Polymers having (E)- and (Z)-olefin moieties were obtained, wherein the (E)-/(Z)-ratios depended on the reaction conditions. The UV-vis absorption edge of (E)-poly(1p-Si1) was positioned at a wavelength longer than that of (Z)-poly(1p-Si1), indicating that (E)-vinylene-linkage extends the conjugation more largely than the (Z)-counterpart. This was also confirmed by fluorescence spectroscopy. Alkaline hydrolysis of ester moieties of these polymers gave the corresponding polymers having carboxy groups. The (E)-polymers showed different solubility in hydrophobic solvents before and after hydrolysis, but the non-hydrolyzed and hydrolyzed (Z)-polymers exhibited the same solubility.
Synthesis of linear tripeptides for right-hand segments of complestatin
Yamada, Yaeko,Akiba, Ai,Arima, Shiho,Okada, Chiharu,Yoshida, Kiminari,Itou, Fumihiro,Kai, Toshitsugu,Satou, Toshiko,Takeda, Kazuyoshi,Harigaya, Yoshihiro
, p. 1277 - 1290 (2007/10/03)
This paper concerns a synthetic study of the right-hand segment of complestatin, an inhibitor of gp120-CD4 receptor. The effective synthesis of four important precursors for the right-hand segment of complestatin is described. Two of them are the precurso