Fmoc-Phe-OH-[15N]

A series of oligo-peptide based catalysts were prepared using Fmoc solid-phase peptide synthesis. It was found that peptides with N-terminal proline residues catalyzed an aldol reaction yielding enantiomeric enriched product. Peptide H-Pro-Glu-Leu-Phe-OH catalyzed the reaction with good activity and moderate enantioselectivity (66% ee). Furthermore, it was shown that an acidic side chain and/or C-termini are essential to catalysis.

Synthetically useful N-Fmoc amino-alkyl isothiocyanates have been described, starting from protected amino acids. These compounds have been synthesized in excellent yields by thiocarbonylation of the monoprotected 1,2-diamines with CS2/TEA/p-TsCl, isolated as stable solids, and completely characterized. The procedure has been extended to the synthesis of amino alkyl isothiocyanates from Boc- and Z-protected amino acids as well. The utility of these isothiocyanates for peptidomimetics synthesis has been demonstrated by employing them in the preparation of a series of dithioureidopeptide esters. Boc-Gly-OH and Boc-Phe-OH derived isothiocyanates 9a and 9c have been obtained as single crystals and their structures solved through X-ray diffraction. They belong to the orthorhombic crystal system, and have a single molecule in the asymmetric unit (Z' = 1). 9a crystallizes in the centrosymmetric space group Pbca, while 9c crystallizes in the noncentrosymmetric space group P2(1)2(1)2(1).

BACKGROUND: Early laboratory detection of Mycobacterium tuberculosis is crucial for controlling tuberculosis. We developed a hydrogel mycobacterial culture method that retains the advantages of both solid and liquid methods in terms of speed, cost, and efficiency.

The development of hydrogels resulting from the self-assembly of low molecular weight (LMW) hydrogelators is a rapidly expanding area of study. Fluorenylmethoxycarbonyl (Fmoc) protected aromatic amino acids derived from phenylalanine (Phe) have been shown to be highly effective LMW hydrogelators. It has been found that side chain functionalization of Fmoc-Phe exerts a significant effect on the self-assembly and hydrogelation behavior of these molecules; fluorinated derivatives, including pentafluorophenylalanine (F(5)-Phe) and 3-F-phenylalanine (3-F-Phe), spontaneously self-assemble into fibrils that form a hydrogel network upon dissolution into water. In this study, Fmoc-F(5)-Phe-OH and Fmoc-3-F-Phe-OH were used to characterize the role of the C-terminal carboxylic acid on the self-assembly and hydrogelation of these derivatives. The C-terminal carboxylic acid moieties of Fmoc-F(5)-Phe-OH and Fmoc-3-F-Phe-OH were converted to C-terminal amide and methyl ester groups in order to perturb the hydrophobicity and hydrogen bond capacity of the C-terminus.