Stella Patrianakou

Comparison of the stepwise and convergent approaches in the solid-phase synthesis of rat Tyro-atriopeptin II

Tyro-Atriopeptin II was synthesized on a 2-chlorotrityl resin by both, the stepwise and the convergent approach. For both methods an Fmoc/tBu(Trt)-based protection scheme was used. The convergent methodology utilizes the sequential condensation of four protected peptide fragments. These were chosen so that after every condensation reaction, the amino-terminal region of the newly formed resin-bound peptide did not contain a β-turn. This ‘designed’ convergent synthesis gave the target peptide in much higher yield and purity than the conventional stepby-step synthesis.

Preparation of optically active cyclic ether derivatives of amino acids and peptides

Treatment of N-tritylmethioninol (1) or peptides (6), incorporating methionyl and amino alcohol residues, with Mel, followed by base mediated cyclisation of the thus derived sulphonium salts, provides the title compounds in excellent yields.

Effect of O-allyl-hydroxy amino acids on protein synthesis and secretion by cultured fat body and salivary glands in the fruit fly Ceratitis capitata

Abstract 1. 1. The amino acid analogs O -allyl-tyrosine, O -allyl-threonine, O -allyl-serine and O -allyl-homoserine, have been synthesized and their effect on protein synthesis and secretion in cultured C. capitata fat body and salivary glands have been studied. 2. 2. The analogs had an inhibitory effect on protein synthesis in both tissues. Moreover, the analogs caused a slight increase in protein secretion in the fat body in comparison to the control. 3. 3. The intracellular transit time of protein secretion in treated and non-treated fat body was found essentially the same (about 10 min).

Simple syntheses of (S)-2- and 4-amino-5-hydroxypentanoic acids

The title compounds were efficiently prepared by selective reductions of α- and γ-methyl (S)-N-tritylglutamates with LiAlH4