Synthesis of Some new hetrocyclic Dervatives For Biological Study

The aim of this study was to develop practical synthetic routes of potential importance for the construction of pharmaceutically important structural motifs and compounds of biological interest utilizing N-acylbenzotriazoles. In addition, the design, synthesis and biological evaluation of novel anti-HIV drug candidates is also discussed. The thesis is presented in five chapters;Chapter 1 starts with description of the synthesis of N-protected free sulfhydryl cysteinoylbenzotriazoles, which on treatment with diverse amino acids and dipeptides afforded the corresponding N-protected free sulfhydryl N-terminal cysteine dipeptides and tripeptides. N-Protected free sulfhydryl cysteine containing dipeptides were converted into the corresponding N-protected free sulfhydryl dipeptidoylbenzotriazoles, which on treatment with amino acids, dipeptides and tripeptides afforded internal cysteine tripeptides, tetrapeptides and pentapeptide each containing N-protected free sulfhydryl groups under mild conditions. Treatment of N-protected free sulfhydryl cysteinoylbenzotriazole with diamines afforded directly the cysteine containing disulfide bridged cyclic peptides.Chapter 2 illustrates the selective N-acylation of various amino acids including unprotected serine and glutamic acid, in the presence of triethylamine at 20 oC using Stable Fmoc, Boc and Alloc benzotriazoles as new protecting reagents to introduce α-amino protecting groups to afford Fmoc, Boc and Alloc protected amino acids free of dipeptide and tripeptide impurities. Fmoc- and Alloc-Gly-Gly-OH dipeptides were prepared by N-acylation of glycylglycine with Fmoc and