80514-64-3Relevant articles and documents
Effects of pH on aggregation and photodynamic activities of cationic zinc phthalocyanines substituted with amides
Wang, Ao,Chen, Xianglan,Zhang, Liu,Zhang, Guangyi,Zhou, Lin,Lu, Shan,Zhou, Jiahong,Wei, Shaohua
, p. 1 - 12 (2014)
This work reports on the effects of pH (especially base addition) on the properties of two cationic phthalocyanines substituted with amide groups. The absorption spectra, photo-stability, singlet oxygen generation ability and photodegradation of CT DNA of
Highly stereoselective syntheses of syn- and anti-1,2-amino alcohols
Hoffman, Robert V.,Maslouh, Najib,Cervantes-Lee, Francisco
, p. 1045 - 1056 (2007/10/03)
The reduction of N-protected amino ketones can be carried stereoselectively to produce either the syn- or anti-amino alcohol diastereomer. Carbamate-protected amino ketones can be reduced predictably and selectively to anti-amino alcohols with LiAlH(O-t-Bu)3 in ethanol at -78°C. N-Trityl-protected amino ketones can be reduced selectively to syn-amino alcohols with LiAlH(O-t-Bu)3 in THF at -5°C.
Stabilized analogs of thymopentin. 1. 4,5-Ketomethylene pseudopeptides
DeGraw, Joseph I.,Almquist, Ronald G.,Hiebert, Charles K.,Colwell, William T.,Crase, Jac,Hayano, Takeshi,Judd, Amrit K.,Dousman, Linda,Smith, R. Lane,Waud, William R.,Uchida, Itsuo
, p. 2386 - 2397 (2007/10/03)
The pentapeptide, thymopentin (Arg1-Lys2-Asp3-Val4-Tyr5) is known for its activity as an immunomodulating drug, but with limited half-life in plasma. In this first paper of a series of three studies, the synthesis of analogs stabilized at the peptide bond between the C-terminal amino acids via insertion of a ketomethylene moiety is described. N-Blocked pseudopeptides containing Val(k)Phe, Ala(k)Phe, and Val(k)Val units were prepared and attached to chloromethyl Merrifield resin via the carboxy terminal. Removal of the N-BOC group by trifluoroacetic acid was followed by sequential coupling with N-BOC dipeptides of aspartic acid to yield resin-bound N-BOC pseudotetrapeptides. Removal of N-BOC and coupling with N-BOC-r-N- tosylarginine followed by total cleavage of blocking groups and resin by HF afforded the target pseudopentapeptides. The analogs were found to compete favorably with thymopentin for binding to CEM cells, but binding was reduced by about 20-30% on average. All analogs showed significant enhancement of half-life versus thymopentin in mouse serum, but most showed only modest improvement in human serum. Insertion of proline or norleucine at position 2 in the chain caused a substantial increase in half-life (3-4-fold), while N- methylnorleucine conferred complete stability in the analogs.