Resolution of the histidine problem for thiol capture--synthesis of a 39-peptide

Peptide and glycopeptide dendrimers. Part II

Recent progress in peptide and glycopeptide chemistry make the preparation of peptide and glycopeptide dendrimers of acceptable purity, with designed structural and immunochemical properties reliable. New methodologies using unprotected peptide building blocks have been developed to further increase the possibilities of their design and improve their preparation and separation. The sophisticated design of peptide and glycopeptide dendrimers has led to their use as antigens and immunogens, for serodiagnosis and other biochemical uses including drug delivery. Dendrimers bearing peptide with predetermined secondary structures are useful tools in protein de novo design. This article covers synthesis and applications of multiple antigen peptides (MAPs), multiple antigen glycopeptides (MAGs), multiple antigen peptides based on sequential oligopeptide carriers (MAP-SOCs), glycodendrimers and template-assembled synthetic proteins (TASPs). In part II the preparation of MAPs, and the utility of glycodendrimers and TASPs are discussed.

Preparation and properties of N alpha-Bpoc-amino acid pentafluorophenyl esters

The preparation and properties are reported of several N alpha-Bpoc -amino acid pentafluorophenyl esters, including those bearing tert-butyl-, allyl- and trityl-based protecting groups. These derivatives have been used in the solid-phase peptide synthesis of several short peptides.

Recent advances in multiple antigen peptides

The goals for the development of multiple antigen peptides (MAP) are to provide a rational and unambiguous system to multimerize different types of synthetic peptide antigens and to attach immunomodulating molecules for targeting and delivery. These goals have been largely realized and new designs of MAPs now permit a broad range of immune responses including CTLs and mucosal IgAs. Furthermore, significant advances by the inventiveness of many laboratories have led to applications of MAPs for serodiagnostic and other biochemical uses including those for drug discovery. An important aspect to accomplish various goals of MAPs is chemistry. New methodologies using unprotected peptides as building blocks have been developed to accommodate new and sophisticated design of MAPs. This review is written based on the personal perspective of my laboratory and will focus on the recent progress in MAPs, together with the chemistry to achieve their synthesis.

Protection of asparagine and glutamine during N alpha-Bpoc-based solid-phase peptide synthesis

In this paper we describe the synthesis and properties of Bpoc-Asn(Trt)-OH, Bpoc-Asn(Trt)-OPfp, Bpoc-Gln(Trt)-OH and Bpoc-Gln(Trt)-OPfp. These derivatives are highly soluble in CH2Cl2 and can be coupled efficiently in solid-phase peptide synthesis. The peptides, acetyl-Ala-Phe-Asn(Trt)-Gly-Leu-Ala-O-Dbf-SH and Boc-Cys(Acm)-Ala-Phe-Gln(Trt)-Gly-Leu-Ala-O-Dbf-SH (where O-Dbf-SH is the peptide ester of 4-mercapto-6-hydroxydibenzofuran) were synthesized by stepwise solid-phase peptide synthesis using N alpha-Bpoc amino acids. We have observed that less than 0.1% of the trityl group is removed from the carboxamide of Gln and Asn during a standard 15 min N alpha-Bpoc deprotection in 0.5% TFA in CH2Cl2.