Evaluation of Peptide Synthesis As Practiced in 53 Different Laboratories

Publisher Summary This chapter presents an evaluation of peptide synthesis as practiced in 53 different laboratories. In a study described in the chapter, a total of 58 crude and 33 purified peptide samples and 42 peptide-resins were supplied for inclusion. Sixteen of the crude peptides were synthesized by Boc chemistry (28%) and 42 by Fmoc chemistry (72%). For peptide assembly, HBTU/HOBt proved to be most popular, followed by carbodiimide-mediated coupling and PyBOP/HOBt. The predominant side chain protecting group strategy for Fmoc-based syntheses was Arg(Pmc), Lys(Boc), Asp(O t Bu), Asn(Trt), and Tyr( t Bu). Exceptions were Arg(Mtr) and Trp(Boc), used in four and two of the syntheses, respectively, and no side-chain protection of Asn, used in seven of the syntheses. The predominant side-chain protecting group strategy for Boc-based syntheses was Arg(Tos), Lys(ClZ), Trp(For), and Tyr(BrZ), with approximately equal use of Asp(OBzl) or Asp(OcHex) and 3 syntheses incorporating Arg(Mts). Of the 42 peptideresins assembled by Fmoc chemistry, 28 were cleaved by Reagent K and 5 by Reagent R. Of the 16 peptide-resins assembled by Boc chemistry, 10 were cleaved by HF containing anisole alone or anisole plus other scavengers.