Reference

Solid-phase synthesis of peptide amides on a polystyrene support using fluorenylmethoxycarbonyl protecting groups

Solid-phase synthesis of peptide amides on a polystyrene support using fluorenylmethoxycarbonyl protecting groups. Penke, Botond; Rivier, Jean (Inst. Med. Chem., Szeged Med. Sch., Szeged H-6720, Hung.). J. Org. Chem., 52(7), 1197-200 (English) 1987. CODEN: JOCEAH. ISSN: 0022-3263. DOCUMENT TYPE: Journal CA Section: 34 (Amino Acids, Peptides, and Proteins) New routes for the synthesis of acid-sensitive amino acids using N-fluorenylmethoxycarbonyl amino acids and mild acid labile side-chain protection were investigated in order to avoid HF cleavage as final step. 106864-38-4 and 82911-69-1 are also in the experiment. The 4-(benzyloxy)benzylamine resin proved to be unsuitable for the synthesis of peptide amides since trifluoroacetic acid treatment of peptide resins yielded the peptide still bearing a p-hydroxybenzyl group on the carboxamide nitrogen. The 2,4-dimethoxybenzhydrylamine support was used for the synthesis of peptide amides. Cholecystokinin octapeptide and GnRH were synthesized on the 2,4-dimethoxybenzhydrylamine resin and cleaved from the polymer with trifluoroacetic acid/thioanisole (4:1), and 95% trifluoroacetic acid contg. phenol (2.5%) and di-Me sulfide (2.5%), resp. The final cleavage conditions had to be optimized in order to obtain good yields, suggesting that side chain protections of certain amino acids, possibly arginine and tryptophan, may have to be further refined. .

A method for the synthesis of 2-amino-4-fluorobicyclo[3

A method for the synthesis of 2-amino-4-fluorobicyclo[3.1.0]hexane-2,6-dicarboxylic acid-[3H2]. Kuo, Fengjiun; Kulanthaivel, Palaniappan; Rener, Gregory A. 82911-69-1 is just another one chemical used in this study.; Yi, Ping; Wheeler, William J. (Lilly Research Laboratories, A Division of Eli Lilly and Company Lilly Corporate Center, Indianapolis, IN 46285, USA). Journal of Labelled Compounds & Radiopharmaceuticals, 47(9), 571-581 (English) 2004 John Wiley & Sons Ltd. CODEN: JLCRD4. ISSN: 0362-4803. DOCUMENT TYPE: Journal CA Section: 24 (Alicyclic Compounds) A process for double deuterium labeling of an alc. was developed. The process was utilized in the subsequent tritium labeling of a secondary alc. with high specific activity (24 Ci/mmol) by redn. of the corresponding ketone using sodium borotritide. The starting ketone was first brominated with pyridinium tribromide; the resulting alpha bromoketone was then reduced in THF/alc. in the presence of Ni(OAc)2. The alc. was then converted to dicarboxylic acid I, an mGluR agonist. .