Oligopeptide Conjugates Research Articles

Water-soluble L-alanine and related oligopeptide conjugates with poly[(R,S)-3-hydroxybutanoic acid] oligomers. Synthesis and structural studies by means of electrospray ionization multistage mass spectrometry

The reactions of (R,S) β-butyrolactone with L-alanine and related oligopeptides (Ala-Ala-Ala) were investigated. The resulting water-soluble oligomers were composed of poly[(R,S)-3-hydroxybutanoic acid] (a-PHB) covalently conjugated to L-alanine and Ala-Ala-Ala oligopeptide. The other chain end was of the carboxylic acid type. The structure of the obtained oligomers was assessed by electrospray ionization multistage mass spectrometry (ESI-MSn) and the respective structural information was completed by IR, NMR, and GPC analyses. The molecular weight and structure of the products could be controlled through reaction conditions. Using this new synthetic approach, a-PHB oligomers with well-defined end groups, as well as respective block copolymers, can be prepared via regioselective ring-opening oligomerization of (R,S)β-butyrolactone induced by amino acids under their zwitterionic form.

Solid-State Synthesis of Oligopeptide Conjugates with Hemin and their Effect on HIV-1 Proteinase

Solid-State Synthesis of Oligopeptide Conjugates with Hemin and their Effect on HIV-1 Proteinase

Monodisperse liquid crystalline peptides

Solid phase peptide synthesis (SPPS) has been used as a synthetic tool to prepare monodisperse mesogen–oligopeptide conjugates with novel molecular architectures. Building upon previous success in this area, we have extended our methodologies to include a mesogenically substituted l-glutamic acid residue, and incorporated this derivative, as well as the l-lysine derivative previously reported, into a variety of new structures. Some novel liquid crystalline materials have been discovered. Bothalpha;-helical and beta;-sheet secondary structures have been explored as alternative scaffolds for the pendant mesogenic groups. The helical systems show most promise in terms of their ease of synthesis and handling, but at the relatively lower levels of mesogenic substitution studied so far, compared to the previously reported homo-oligopeptide materials, mesophases are not observed. The beta;-sheet materials prepared are rather insoluble and too high melting to have any practical value as thermotropic materials without further manipulation of their structures.

Doxorubicin and DNA minor groove-binding oligopeptide conjugates as anticancer agents

Doxorubicin (Dor) and DNA minor groove-binding oligopeptide conjugates have been synthesized and their antitumor activities tested in vitro against KB cells. These new Dor analogues are less toxic to KB cells than the parent Dor.